changeset 67:01ba3c658576

fmt: upgrade to 5.1.0, closes #883 @20m
author David Demelier <markand@malikania.fr>
date Fri, 13 Jul 2018 13:15:12 +0200
parents 177c7e511bcb
children 1a32b6d17c8e
files VERSION.fmt.txt fmt/CMakeLists.txt fmt/format.cc fmt/format.h fmt/include/fmt/core.h fmt/include/fmt/format-inl.h fmt/include/fmt/format.h fmt/include/fmt/ostream.h fmt/include/fmt/posix.h fmt/include/fmt/printf.h fmt/include/fmt/ranges.h fmt/include/fmt/time.h fmt/src/format.cc fmt/src/posix.cc fmt/support/cmake/cxx14.cmake tests/fmt/main.cpp
diffstat 16 files changed, 8038 insertions(+), 4847 deletions(-) [+]
line wrap: on
line diff
--- a/VERSION.fmt.txt	Fri Jul 13 12:57:10 2018 +0200
+++ b/VERSION.fmt.txt	Fri Jul 13 13:15:12 2018 +0200
@@ -1,1 +1,1 @@
-3.0.1
+5.1.0
--- a/fmt/CMakeLists.txt	Fri Jul 13 12:57:10 2018 +0200
+++ b/fmt/CMakeLists.txt	Fri Jul 13 13:15:12 2018 +0200
@@ -1,27 +1,52 @@
-#
-# CMakeLists.txt -- CMake build system for cppformat
-#
-# Copyright (c) 2016-2018 David Demelier <markand@malikania.fr>
-#
-# Permission to use, copy, modify, and/or distribute this software for any
-# purpose with or without fee is hereby granted, provided that the above
-# copyright notice and this permission notice appear in all copies.
-#
-# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
-# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
-# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
-# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
-# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
-# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
-#
+cmake_minimum_required(VERSION 3.1.0)
+project(fmt)
+
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH}
+  "${CMAKE_CURRENT_SOURCE_DIR}/support/cmake")
+
+include(cxx14)
+include(CheckCXXCompilerFlag)
+
+include(CheckSymbolExists)
+
+if (WIN32)
+    check_symbol_exists(open io.h HAVE_OPEN)
+else ()
+    check_symbol_exists(open fcntl.h HAVE_OPEN)
+endif ()
 
-cmake_minimum_required(VERSION 3.0)
-project(libfmt)
-add_library(libfmt format.cc format.h)
+set(
+    HEADERS
+    ${libfmt_SOURCE_DIR}/include/fmt/core.h
+    ${libfmt_SOURCE_DIR}/include/fmt/format.h
+    ${libfmt_SOURCE_DIR}/include/fmt/format-inl.h
+    ${libfmt_SOURCE_DIR}/include/fmt/ostream.h
+    ${libfmt_SOURCE_DIR}/include/fmt/printf.h
+    ${libfmt_SOURCE_DIR}/include/fmt/time.h
+    ${libfmt_SOURCE_DIR}/include/fmt/ranges.h
+)
+
+set(FMT_SOURCES ${libfmt_SOURCE_DIR}/src/format.cc)
+
+if (HAVE_OPEN)
+    set(FMT_HEADERS ${FMT_HEADERS} ${libfmt_SOURCE_DIR}/include/fmt/posix.h)
+    set(FMT_SOURCES ${FMT_SOURCES} ${libfmt_SOURCE_DIR}/src/posix.cc)
+endif ()
+
+add_library(libfmt ${FMT_SOURCES} ${FMT_HEADERS})
+set_target_properties(libfmt PROPERTIES PREFIX "")
+
 target_include_directories(
     libfmt
     PUBLIC
-        $<BUILD_INTERFACE:${libfmt_SOURCE_DIR}>
+        $<BUILD_INTERFACE:${fmt_SOURCE_DIR}/include>
 )
-set_target_properties(libfmt PROPERTIES PREFIX "")
+
+if (BUILD_SHARED_LIBS)
+    if (UNIX AND NOT APPLE)
+        # Fix rpmlint warning:
+        # unused-direct-shlib-dependency /usr/lib/libformat.so.1.1.0 /lib/libm.so.6.
+        target_link_libraries(libfmt -Wl,--as-needed)
+    endif ()
+    target_compile_definitions(libfmt PRIVATE FMT_EXPORT INTERFACE FMT_SHARED)
+endif ()
--- a/fmt/format.cc	Fri Jul 13 12:57:10 2018 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,940 +0,0 @@
-/*
- Formatting library for C++
-
- Copyright (c) 2012 - 2016, Victor Zverovich
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
-
- 1. Redistributions of source code must retain the above copyright notice, this
-    list of conditions and the following disclaimer.
- 2. Redistributions in binary form must reproduce the above copyright notice,
-    this list of conditions and the following disclaimer in the documentation
-    and/or other materials provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
- ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "format.h"
-
-#include <string.h>
-
-#include <cctype>
-#include <cerrno>
-#include <climits>
-#include <cmath>
-#include <cstdarg>
-#include <cstddef>  // for std::ptrdiff_t
-
-#if defined(_WIN32) && defined(__MINGW32__)
-# include <cstring>
-#endif
-
-#if FMT_USE_WINDOWS_H
-# if defined(NOMINMAX) || defined(FMT_WIN_MINMAX)
-#  include <windows.h>
-# else
-#  define NOMINMAX
-#  include <windows.h>
-#  undef NOMINMAX
-# endif
-#endif
-
-using fmt::internal::Arg;
-
-#if FMT_EXCEPTIONS
-# define FMT_TRY try
-# define FMT_CATCH(x) catch (x)
-#else
-# define FMT_TRY if (true)
-# define FMT_CATCH(x) if (false)
-#endif
-
-#ifdef _MSC_VER
-# pragma warning(push)
-# pragma warning(disable: 4127)  // conditional expression is constant
-# pragma warning(disable: 4702)  // unreachable code
-// Disable deprecation warning for strerror. The latter is not called but
-// MSVC fails to detect it.
-# pragma warning(disable: 4996)
-#endif
-
-// Dummy implementations of strerror_r and strerror_s called if corresponding
-// system functions are not available.
-static inline fmt::internal::Null<> strerror_r(int, char *, ...) {
-  return fmt::internal::Null<>();
-}
-static inline fmt::internal::Null<> strerror_s(char *, std::size_t, ...) {
-  return fmt::internal::Null<>();
-}
-
-namespace fmt {
-
-FMT_FUNC internal::RuntimeError::~RuntimeError() throw() {}
-FMT_FUNC FormatError::~FormatError() throw() {}
-FMT_FUNC SystemError::~SystemError() throw() {}
-
-namespace {
-
-#ifndef _MSC_VER
-# define FMT_SNPRINTF snprintf
-#else  // _MSC_VER
-inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
-  va_list args;
-  va_start(args, format);
-  int result = vsnprintf_s(buffer, size, _TRUNCATE, format, args);
-  va_end(args);
-  return result;
-}
-# define FMT_SNPRINTF fmt_snprintf
-#endif  // _MSC_VER
-
-#if defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
-# define FMT_SWPRINTF snwprintf
-#else
-# define FMT_SWPRINTF swprintf
-#endif // defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
-
-// Checks if a value fits in int - used to avoid warnings about comparing
-// signed and unsigned integers.
-template <bool IsSigned>
-struct IntChecker {
-  template <typename T>
-  static bool fits_in_int(T value) {
-    unsigned max = INT_MAX;
-    return value <= max;
-  }
-  static bool fits_in_int(bool) { return true; }
-};
-
-template <>
-struct IntChecker<true> {
-  template <typename T>
-  static bool fits_in_int(T value) {
-    return value >= INT_MIN && value <= INT_MAX;
-  }
-  static bool fits_in_int(int) { return true; }
-};
-
-const char RESET_COLOR[] = "\x1b[0m";
-
-typedef void (*FormatFunc)(Writer &, int, StringRef);
-
-// Portable thread-safe version of strerror.
-// Sets buffer to point to a string describing the error code.
-// This can be either a pointer to a string stored in buffer,
-// or a pointer to some static immutable string.
-// Returns one of the following values:
-//   0      - success
-//   ERANGE - buffer is not large enough to store the error message
-//   other  - failure
-// Buffer should be at least of size 1.
-int safe_strerror(
-    int error_code, char *&buffer, std::size_t buffer_size) FMT_NOEXCEPT {
-  FMT_ASSERT(buffer != 0 && buffer_size != 0, "invalid buffer");
-
-  class StrError {
-   private:
-    int error_code_;
-    char *&buffer_;
-    std::size_t buffer_size_;
-
-    // A noop assignment operator to avoid bogus warnings.
-    void operator=(const StrError &) {}
-
-    // Handle the result of XSI-compliant version of strerror_r.
-    int handle(int result) {
-      // glibc versions before 2.13 return result in errno.
-      return result == -1 ? errno : result;
-    }
-
-    // Handle the result of GNU-specific version of strerror_r.
-    int handle(char *message) {
-      // If the buffer is full then the message is probably truncated.
-      if (message == buffer_ && strlen(buffer_) == buffer_size_ - 1)
-        return ERANGE;
-      buffer_ = message;
-      return 0;
-    }
-
-    // Handle the case when strerror_r is not available.
-    int handle(internal::Null<>) {
-      return fallback(strerror_s(buffer_, buffer_size_, error_code_));
-    }
-
-    // Fallback to strerror_s when strerror_r is not available.
-    int fallback(int result) {
-      // If the buffer is full then the message is probably truncated.
-      return result == 0 && strlen(buffer_) == buffer_size_ - 1 ?
-            ERANGE : result;
-    }
-
-    // Fallback to strerror if strerror_r and strerror_s are not available.
-    int fallback(internal::Null<>) {
-      errno = 0;
-      buffer_ = strerror(error_code_);
-      return errno;
-    }
-
-   public:
-    StrError(int err_code, char *&buf, std::size_t buf_size)
-      : error_code_(err_code), buffer_(buf), buffer_size_(buf_size) {}
-
-    int run() {
-      strerror_r(0, 0, "");  // Suppress a warning about unused strerror_r.
-      return handle(strerror_r(error_code_, buffer_, buffer_size_));
-    }
-  };
-  return StrError(error_code, buffer, buffer_size).run();
-}
-
-void format_error_code(Writer &out, int error_code,
-                       StringRef message) FMT_NOEXCEPT {
-  // Report error code making sure that the output fits into
-  // INLINE_BUFFER_SIZE to avoid dynamic memory allocation and potential
-  // bad_alloc.
-  out.clear();
-  static const char SEP[] = ": ";
-  static const char ERROR_STR[] = "error ";
-  // Subtract 2 to account for terminating null characters in SEP and ERROR_STR.
-  std::size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
-  typedef internal::IntTraits<int>::MainType MainType;
-  MainType abs_value = static_cast<MainType>(error_code);
-  if (internal::is_negative(error_code)) {
-    abs_value = 0 - abs_value;
-    ++error_code_size;
-  }
-  error_code_size += internal::count_digits(abs_value);
-  if (message.size() <= internal::INLINE_BUFFER_SIZE - error_code_size)
-    out << message << SEP;
-  out << ERROR_STR << error_code;
-  assert(out.size() <= internal::INLINE_BUFFER_SIZE);
-}
-
-void report_error(FormatFunc func, int error_code,
-                  StringRef message) FMT_NOEXCEPT {
-  MemoryWriter full_message;
-  func(full_message, error_code, message);
-  // Use Writer::data instead of Writer::c_str to avoid potential memory
-  // allocation.
-  std::fwrite(full_message.data(), full_message.size(), 1, stderr);
-  std::fputc('\n', stderr);
-}
-
-// IsZeroInt::visit(arg) returns true iff arg is a zero integer.
-class IsZeroInt : public ArgVisitor<IsZeroInt, bool> {
- public:
-  template <typename T>
-  bool visit_any_int(T value) { return value == 0; }
-};
-
-// Checks if an argument is a valid printf width specifier and sets
-// left alignment if it is negative.
-class WidthHandler : public ArgVisitor<WidthHandler, unsigned> {
- private:
-  FormatSpec &spec_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(WidthHandler);
-
- public:
-  explicit WidthHandler(FormatSpec &spec) : spec_(spec) {}
-
-  void report_unhandled_arg() {
-    FMT_THROW(FormatError("width is not integer"));
-  }
-
-  template <typename T>
-  unsigned visit_any_int(T value) {
-    typedef typename internal::IntTraits<T>::MainType UnsignedType;
-    UnsignedType width = static_cast<UnsignedType>(value);
-    if (internal::is_negative(value)) {
-      spec_.align_ = ALIGN_LEFT;
-      width = 0 - width;
-    }
-    if (width > INT_MAX)
-      FMT_THROW(FormatError("number is too big"));
-    return static_cast<unsigned>(width);
-  }
-};
-
-class PrecisionHandler : public ArgVisitor<PrecisionHandler, int> {
- public:
-  void report_unhandled_arg() {
-    FMT_THROW(FormatError("precision is not integer"));
-  }
-
-  template <typename T>
-  int visit_any_int(T value) {
-    if (!IntChecker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
-      FMT_THROW(FormatError("number is too big"));
-    return static_cast<int>(value);
-  }
-};
-
-template <typename T, typename U>
-struct is_same {
-  enum { value = 0 };
-};
-
-template <typename T>
-struct is_same<T, T> {
-  enum { value = 1 };
-};
-
-// An argument visitor that converts an integer argument to T for printf,
-// if T is an integral type. If T is void, the argument is converted to
-// corresponding signed or unsigned type depending on the type specifier:
-// 'd' and 'i' - signed, other - unsigned)
-template <typename T = void>
-class ArgConverter : public ArgVisitor<ArgConverter<T>, void> {
- private:
-  internal::Arg &arg_;
-  wchar_t type_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(ArgConverter);
-
- public:
-  ArgConverter(internal::Arg &arg, wchar_t type)
-    : arg_(arg), type_(type) {}
-
-  void visit_bool(bool value) {
-    if (type_ != 's')
-      visit_any_int(value);
-  }
-
-  template <typename U>
-  void visit_any_int(U value) {
-    bool is_signed = type_ == 'd' || type_ == 'i';
-    using internal::Arg;
-    typedef typename internal::Conditional<
-        is_same<T, void>::value, U, T>::type TargetType;
-    if (sizeof(TargetType) <= sizeof(int)) {
-      // Extra casts are used to silence warnings.
-      if (is_signed) {
-        arg_.type = Arg::INT;
-        arg_.int_value = static_cast<int>(static_cast<TargetType>(value));
-      } else {
-        arg_.type = Arg::UINT;
-        typedef typename internal::MakeUnsigned<TargetType>::Type Unsigned;
-        arg_.uint_value = static_cast<unsigned>(static_cast<Unsigned>(value));
-      }
-    } else {
-      if (is_signed) {
-        arg_.type = Arg::LONG_LONG;
-        // glibc's printf doesn't sign extend arguments of smaller types:
-        //   std::printf("%lld", -42);  // prints "4294967254"
-        // but we don't have to do the same because it's a UB.
-        arg_.long_long_value = static_cast<LongLong>(value);
-      } else {
-        arg_.type = Arg::ULONG_LONG;
-        arg_.ulong_long_value =
-            static_cast<typename internal::MakeUnsigned<U>::Type>(value);
-      }
-    }
-  }
-};
-
-// Converts an integer argument to char for printf.
-class CharConverter : public ArgVisitor<CharConverter, void> {
- private:
-  internal::Arg &arg_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(CharConverter);
-
- public:
-  explicit CharConverter(internal::Arg &arg) : arg_(arg) {}
-
-  template <typename T>
-  void visit_any_int(T value) {
-    arg_.type = internal::Arg::CHAR;
-    arg_.int_value = static_cast<char>(value);
-  }
-};
-}  // namespace
-
-namespace internal {
-
-template <typename Char>
-class PrintfArgFormatter :
-    public ArgFormatterBase<PrintfArgFormatter<Char>, Char> {
-
-  void write_null_pointer() {
-    this->spec().type_ = 0;
-    this->write("(nil)");
-  }
-
-  typedef ArgFormatterBase<PrintfArgFormatter<Char>, Char> Base;
-
- public:
-  PrintfArgFormatter(BasicWriter<Char> &w, FormatSpec &s)
-  : ArgFormatterBase<PrintfArgFormatter<Char>, Char>(w, s) {}
-
-  void visit_bool(bool value) {
-    FormatSpec &fmt_spec = this->spec();
-    if (fmt_spec.type_ != 's')
-      return this->visit_any_int(value);
-    fmt_spec.type_ = 0;
-    this->write(value);
-  }
-
-  void visit_char(int value) {
-    const FormatSpec &fmt_spec = this->spec();
-    BasicWriter<Char> &w = this->writer();
-    if (fmt_spec.type_ && fmt_spec.type_ != 'c')
-      w.write_int(value, fmt_spec);
-    typedef typename BasicWriter<Char>::CharPtr CharPtr;
-    CharPtr out = CharPtr();
-    if (fmt_spec.width_ > 1) {
-      Char fill = ' ';
-      out = w.grow_buffer(fmt_spec.width_);
-      if (fmt_spec.align_ != ALIGN_LEFT) {
-        std::fill_n(out, fmt_spec.width_ - 1, fill);
-        out += fmt_spec.width_ - 1;
-      } else {
-        std::fill_n(out + 1, fmt_spec.width_ - 1, fill);
-      }
-    } else {
-      out = w.grow_buffer(1);
-    }
-    *out = static_cast<Char>(value);
-  }
-
-  void visit_cstring(const char *value) {
-    if (value)
-      Base::visit_cstring(value);
-    else if (this->spec().type_ == 'p')
-      write_null_pointer();
-    else
-      this->write("(null)");
-  }
-
-  void visit_pointer(const void *value) {
-    if (value)
-      return Base::visit_pointer(value);
-    this->spec().type_ = 0;
-    write_null_pointer();
-  }
-
-  void visit_custom(Arg::CustomValue c) {
-    BasicFormatter<Char> formatter(ArgList(), this->writer());
-    const Char format_str[] = {'}', 0};
-    const Char *format = format_str;
-    c.format(&formatter, c.value, &format);
-  }
-};
-}  // namespace internal
-}  // namespace fmt
-
-FMT_FUNC void fmt::SystemError::init(
-    int err_code, CStringRef format_str, ArgList args) {
-  error_code_ = err_code;
-  MemoryWriter w;
-  internal::format_system_error(w, err_code, format(format_str, args));
-  std::runtime_error &base = *this;
-  base = std::runtime_error(w.str());
-}
-
-template <typename T>
-int fmt::internal::CharTraits<char>::format_float(
-    char *buffer, std::size_t size, const char *format,
-    unsigned width, int precision, T value) {
-  if (width == 0) {
-    return precision < 0 ?
-        FMT_SNPRINTF(buffer, size, format, value) :
-        FMT_SNPRINTF(buffer, size, format, precision, value);
-  }
-  return precision < 0 ?
-      FMT_SNPRINTF(buffer, size, format, width, value) :
-      FMT_SNPRINTF(buffer, size, format, width, precision, value);
-}
-
-template <typename T>
-int fmt::internal::CharTraits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    unsigned width, int precision, T value) {
-  if (width == 0) {
-    return precision < 0 ?
-        FMT_SWPRINTF(buffer, size, format, value) :
-        FMT_SWPRINTF(buffer, size, format, precision, value);
-  }
-  return precision < 0 ?
-      FMT_SWPRINTF(buffer, size, format, width, value) :
-      FMT_SWPRINTF(buffer, size, format, width, precision, value);
-}
-
-template <typename T>
-const char fmt::internal::BasicData<T>::DIGITS[] =
-    "0001020304050607080910111213141516171819"
-    "2021222324252627282930313233343536373839"
-    "4041424344454647484950515253545556575859"
-    "6061626364656667686970717273747576777879"
-    "8081828384858687888990919293949596979899";
-
-#define FMT_POWERS_OF_10(factor) \
-  factor * 10, \
-  factor * 100, \
-  factor * 1000, \
-  factor * 10000, \
-  factor * 100000, \
-  factor * 1000000, \
-  factor * 10000000, \
-  factor * 100000000, \
-  factor * 1000000000
-
-template <typename T>
-const uint32_t fmt::internal::BasicData<T>::POWERS_OF_10_32[] = {
-  0, FMT_POWERS_OF_10(1)
-};
-
-template <typename T>
-const uint64_t fmt::internal::BasicData<T>::POWERS_OF_10_64[] = {
-  0,
-  FMT_POWERS_OF_10(1),
-  FMT_POWERS_OF_10(fmt::ULongLong(1000000000)),
-  // Multiply several constants instead of using a single long long constant
-  // to avoid warnings about C++98 not supporting long long.
-  fmt::ULongLong(1000000000) * fmt::ULongLong(1000000000) * 10
-};
-
-FMT_FUNC void fmt::internal::report_unknown_type(char code, const char *type) {
-  (void)type;
-  if (std::isprint(static_cast<unsigned char>(code))) {
-    FMT_THROW(fmt::FormatError(
-        fmt::format("unknown format code '{}' for {}", code, type)));
-  }
-  FMT_THROW(fmt::FormatError(
-      fmt::format("unknown format code '\\x{:02x}' for {}",
-        static_cast<unsigned>(code), type)));
-}
-
-#if FMT_USE_WINDOWS_H
-
-FMT_FUNC fmt::internal::UTF8ToUTF16::UTF8ToUTF16(fmt::StringRef s) {
-  static const char ERROR_MSG[] = "cannot convert string from UTF-8 to UTF-16";
-  if (s.size() > INT_MAX)
-    FMT_THROW(WindowsError(ERROR_INVALID_PARAMETER, ERROR_MSG));
-  int s_size = static_cast<int>(s.size());
-  int length = MultiByteToWideChar(
-      CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, 0, 0);
-  if (length == 0)
-    FMT_THROW(WindowsError(GetLastError(), ERROR_MSG));
-  buffer_.resize(length + 1);
-  length = MultiByteToWideChar(
-    CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, &buffer_[0], length);
-  if (length == 0)
-    FMT_THROW(WindowsError(GetLastError(), ERROR_MSG));
-  buffer_[length] = 0;
-}
-
-FMT_FUNC fmt::internal::UTF16ToUTF8::UTF16ToUTF8(fmt::WStringRef s) {
-  if (int error_code = convert(s)) {
-    FMT_THROW(WindowsError(error_code,
-        "cannot convert string from UTF-16 to UTF-8"));
-  }
-}
-
-FMT_FUNC int fmt::internal::UTF16ToUTF8::convert(fmt::WStringRef s) {
-  if (s.size() > INT_MAX)
-    return ERROR_INVALID_PARAMETER;
-  int s_size = static_cast<int>(s.size());
-  int length = WideCharToMultiByte(CP_UTF8, 0, s.data(), s_size, 0, 0, 0, 0);
-  if (length == 0)
-    return GetLastError();
-  buffer_.resize(length + 1);
-  length = WideCharToMultiByte(
-    CP_UTF8, 0, s.data(), s_size, &buffer_[0], length, 0, 0);
-  if (length == 0)
-    return GetLastError();
-  buffer_[length] = 0;
-  return 0;
-}
-
-FMT_FUNC void fmt::WindowsError::init(
-    int err_code, CStringRef format_str, ArgList args) {
-  error_code_ = err_code;
-  MemoryWriter w;
-  internal::format_windows_error(w, err_code, format(format_str, args));
-  std::runtime_error &base = *this;
-  base = std::runtime_error(w.str());
-}
-
-FMT_FUNC void fmt::internal::format_windows_error(
-    fmt::Writer &out, int error_code,
-    fmt::StringRef message) FMT_NOEXCEPT {
-  FMT_TRY {
-    MemoryBuffer<wchar_t, INLINE_BUFFER_SIZE> buffer;
-    buffer.resize(INLINE_BUFFER_SIZE);
-    for (;;) {
-      wchar_t *system_message = &buffer[0];
-      int result = FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
-                                  0, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
-                                  system_message, static_cast<uint32_t>(buffer.size()), 0);
-      if (result != 0) {
-        UTF16ToUTF8 utf8_message;
-        if (utf8_message.convert(system_message) == ERROR_SUCCESS) {
-          out << message << ": " << utf8_message;
-          return;
-        }
-        break;
-      }
-      if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
-        break;  // Can't get error message, report error code instead.
-      buffer.resize(buffer.size() * 2);
-    }
-  } FMT_CATCH(...) {}
-  fmt::format_error_code(out, error_code, message);  // 'fmt::' is for bcc32.
-}
-
-#endif  // FMT_USE_WINDOWS_H
-
-FMT_FUNC void fmt::internal::format_system_error(
-    fmt::Writer &out, int error_code,
-    fmt::StringRef message) FMT_NOEXCEPT {
-  FMT_TRY {
-    MemoryBuffer<char, INLINE_BUFFER_SIZE> buffer;
-    buffer.resize(INLINE_BUFFER_SIZE);
-    for (;;) {
-      char *system_message = &buffer[0];
-      int result = safe_strerror(error_code, system_message, buffer.size());
-      if (result == 0) {
-        out << message << ": " << system_message;
-        return;
-      }
-      if (result != ERANGE)
-        break;  // Can't get error message, report error code instead.
-      buffer.resize(buffer.size() * 2);
-    }
-  } FMT_CATCH(...) {}
-  fmt::format_error_code(out, error_code, message);  // 'fmt::' is for bcc32.
-}
-
-template <typename Char>
-void fmt::internal::ArgMap<Char>::init(const ArgList &args) {
-  if (!map_.empty())
-    return;
-  typedef internal::NamedArg<Char> NamedArg;
-  const NamedArg *named_arg = 0;
-  bool use_values =
-      args.type(ArgList::MAX_PACKED_ARGS - 1) == internal::Arg::NONE;
-  if (use_values) {
-    for (unsigned i = 0;/*nothing*/; ++i) {
-      internal::Arg::Type arg_type = args.type(i);
-      switch (arg_type) {
-      case internal::Arg::NONE:
-        return;
-      case internal::Arg::NAMED_ARG:
-        named_arg = static_cast<const NamedArg*>(args.values_[i].pointer);
-        map_.push_back(Pair(named_arg->name, *named_arg));
-        break;
-      default:
-        /*nothing*/;
-      }
-    }
-    return;
-  }
-  for (unsigned i = 0; i != ArgList::MAX_PACKED_ARGS; ++i) {
-    internal::Arg::Type arg_type = args.type(i);
-    if (arg_type == internal::Arg::NAMED_ARG) {
-      named_arg = static_cast<const NamedArg*>(args.args_[i].pointer);
-      map_.push_back(Pair(named_arg->name, *named_arg));
-    }
-  }
-  for (unsigned i = ArgList::MAX_PACKED_ARGS;/*nothing*/; ++i) {
-    switch (args.args_[i].type) {
-    case internal::Arg::NONE:
-      return;
-    case internal::Arg::NAMED_ARG:
-      named_arg = static_cast<const NamedArg*>(args.args_[i].pointer);
-      map_.push_back(Pair(named_arg->name, *named_arg));
-      break;
-    default:
-      /*nothing*/;
-    }
-  }
-}
-
-template <typename Char>
-void fmt::internal::FixedBuffer<Char>::grow(std::size_t) {
-  FMT_THROW(std::runtime_error("buffer overflow"));
-}
-
-FMT_FUNC Arg fmt::internal::FormatterBase::do_get_arg(
-    unsigned arg_index, const char *&error) {
-  Arg arg = args_[arg_index];
-  switch (arg.type) {
-  case Arg::NONE:
-    error = "argument index out of range";
-    break;
-  case Arg::NAMED_ARG:
-    arg = *static_cast<const internal::Arg*>(arg.pointer);
-    break;
-  default:
-    /*nothing*/;
-  }
-  return arg;
-}
-
-template <typename Char>
-void fmt::internal::PrintfFormatter<Char>::parse_flags(
-    FormatSpec &spec, const Char *&s) {
-  for (;;) {
-    switch (*s++) {
-      case '-':
-        spec.align_ = ALIGN_LEFT;
-        break;
-      case '+':
-        spec.flags_ |= SIGN_FLAG | PLUS_FLAG;
-        break;
-      case '0':
-        spec.fill_ = '0';
-        break;
-      case ' ':
-        spec.flags_ |= SIGN_FLAG;
-        break;
-      case '#':
-        spec.flags_ |= HASH_FLAG;
-        break;
-      default:
-        --s;
-        return;
-    }
-  }
-}
-
-template <typename Char>
-Arg fmt::internal::PrintfFormatter<Char>::get_arg(
-    const Char *s, unsigned arg_index) {
-  (void)s;
-  const char *error = 0;
-  Arg arg = arg_index == UINT_MAX ?
-    next_arg(error) : FormatterBase::get_arg(arg_index - 1, error);
-  if (error)
-    FMT_THROW(FormatError(!*s ? "invalid format string" : error));
-  return arg;
-}
-
-template <typename Char>
-unsigned fmt::internal::PrintfFormatter<Char>::parse_header(
-  const Char *&s, FormatSpec &spec) {
-  unsigned arg_index = UINT_MAX;
-  Char c = *s;
-  if (c >= '0' && c <= '9') {
-    // Parse an argument index (if followed by '$') or a width possibly
-    // preceded with '0' flag(s).
-    unsigned value = parse_nonnegative_int(s);
-    if (*s == '$') {  // value is an argument index
-      ++s;
-      arg_index = value;
-    } else {
-      if (c == '0')
-        spec.fill_ = '0';
-      if (value != 0) {
-        // Nonzero value means that we parsed width and don't need to
-        // parse it or flags again, so return now.
-        spec.width_ = value;
-        return arg_index;
-      }
-    }
-  }
-  parse_flags(spec, s);
-  // Parse width.
-  if (*s >= '0' && *s <= '9') {
-    spec.width_ = parse_nonnegative_int(s);
-  } else if (*s == '*') {
-    ++s;
-    spec.width_ = WidthHandler(spec).visit(get_arg(s));
-  }
-  return arg_index;
-}
-
-template <typename Char>
-void fmt::internal::PrintfFormatter<Char>::format(
-    BasicWriter<Char> &writer, BasicCStringRef<Char> format_str) {
-  const Char *start = format_str.c_str();
-  const Char *s = start;
-  while (*s) {
-    Char c = *s++;
-    if (c != '%') continue;
-    if (*s == c) {
-      write(writer, start, s);
-      start = ++s;
-      continue;
-    }
-    write(writer, start, s - 1);
-
-    FormatSpec spec;
-    spec.align_ = ALIGN_RIGHT;
-
-    // Parse argument index, flags and width.
-    unsigned arg_index = parse_header(s, spec);
-
-    // Parse precision.
-    if (*s == '.') {
-      ++s;
-      if ('0' <= *s && *s <= '9') {
-        spec.precision_ = static_cast<int>(parse_nonnegative_int(s));
-      } else if (*s == '*') {
-        ++s;
-        spec.precision_ = PrecisionHandler().visit(get_arg(s));
-      }
-    }
-
-    Arg arg = get_arg(s, arg_index);
-    if (spec.flag(HASH_FLAG) && IsZeroInt().visit(arg))
-      spec.flags_ &= ~to_unsigned<int>(HASH_FLAG);
-    if (spec.fill_ == '0') {
-      if (arg.type <= Arg::LAST_NUMERIC_TYPE)
-        spec.align_ = ALIGN_NUMERIC;
-      else
-        spec.fill_ = ' ';  // Ignore '0' flag for non-numeric types.
-    }
-
-    // Parse length and convert the argument to the required type.
-    switch (*s++) {
-    case 'h':
-      if (*s == 'h')
-        ArgConverter<signed char>(arg, *++s).visit(arg);
-      else
-        ArgConverter<short>(arg, *s).visit(arg);
-      break;
-    case 'l':
-      if (*s == 'l')
-        ArgConverter<fmt::LongLong>(arg, *++s).visit(arg);
-      else
-        ArgConverter<long>(arg, *s).visit(arg);
-      break;
-    case 'j':
-      ArgConverter<intmax_t>(arg, *s).visit(arg);
-      break;
-    case 'z':
-      ArgConverter<std::size_t>(arg, *s).visit(arg);
-      break;
-    case 't':
-      ArgConverter<std::ptrdiff_t>(arg, *s).visit(arg);
-      break;
-    case 'L':
-      // printf produces garbage when 'L' is omitted for long double, no
-      // need to do the same.
-      break;
-    default:
-      --s;
-      ArgConverter<void>(arg, *s).visit(arg);
-    }
-
-    // Parse type.
-    if (!*s)
-      FMT_THROW(FormatError("invalid format string"));
-    spec.type_ = static_cast<char>(*s++);
-    if (arg.type <= Arg::LAST_INTEGER_TYPE) {
-      // Normalize type.
-      switch (spec.type_) {
-      case 'i': case 'u':
-        spec.type_ = 'd';
-        break;
-      case 'c':
-        // TODO: handle wchar_t
-        CharConverter(arg).visit(arg);
-        break;
-      }
-    }
-
-    start = s;
-
-    // Format argument.
-    internal::PrintfArgFormatter<Char>(writer, spec).visit(arg);
-  }
-  write(writer, start, s);
-}
-
-FMT_FUNC void fmt::report_system_error(
-    int error_code, fmt::StringRef message) FMT_NOEXCEPT {
-  // 'fmt::' is for bcc32.
-  fmt::report_error(internal::format_system_error, error_code, message);
-}
-
-#if FMT_USE_WINDOWS_H
-FMT_FUNC void fmt::report_windows_error(
-    int error_code, fmt::StringRef message) FMT_NOEXCEPT {
-  // 'fmt::' is for bcc32.
-  fmt::report_error(internal::format_windows_error, error_code, message);
-}
-#endif
-
-FMT_FUNC void fmt::print(std::FILE *f, CStringRef format_str, ArgList args) {
-  MemoryWriter w;
-  w.write(format_str, args);
-  std::fwrite(w.data(), 1, w.size(), f);
-}
-
-FMT_FUNC void fmt::print(CStringRef format_str, ArgList args) {
-  print(stdout, format_str, args);
-}
-
-FMT_FUNC void fmt::print_colored(Color c, CStringRef format, ArgList args) {
-  char escape[] = "\x1b[30m";
-  escape[3] = static_cast<char>('0' + c);
-  std::fputs(escape, stdout);
-  print(format, args);
-  std::fputs(RESET_COLOR, stdout);
-}
-
-FMT_FUNC int fmt::fprintf(std::FILE *f, CStringRef format, ArgList args) {
-  MemoryWriter w;
-  printf(w, format, args);
-  std::size_t size = w.size();
-  return std::fwrite(w.data(), 1, size, f) < size ? -1 : static_cast<int>(size);
-}
-
-#ifndef FMT_HEADER_ONLY
-
-template struct fmt::internal::BasicData<void>;
-
-// Explicit instantiations for char.
-
-template void fmt::internal::FixedBuffer<char>::grow(std::size_t);
-
-template void fmt::internal::ArgMap<char>::init(const fmt::ArgList &args);
-
-template void fmt::internal::PrintfFormatter<char>::format(
-  BasicWriter<char> &writer, CStringRef format);
-
-template int fmt::internal::CharTraits<char>::format_float(
-    char *buffer, std::size_t size, const char *format,
-    unsigned width, int precision, double value);
-
-template int fmt::internal::CharTraits<char>::format_float(
-    char *buffer, std::size_t size, const char *format,
-    unsigned width, int precision, long double value);
-
-// Explicit instantiations for wchar_t.
-
-template void fmt::internal::FixedBuffer<wchar_t>::grow(std::size_t);
-
-template void fmt::internal::ArgMap<wchar_t>::init(const fmt::ArgList &args);
-
-template void fmt::internal::PrintfFormatter<wchar_t>::format(
-    BasicWriter<wchar_t> &writer, WCStringRef format);
-
-template int fmt::internal::CharTraits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    unsigned width, int precision, double value);
-
-template int fmt::internal::CharTraits<wchar_t>::format_float(
-    wchar_t *buffer, std::size_t size, const wchar_t *format,
-    unsigned width, int precision, long double value);
-
-#endif  // FMT_HEADER_ONLY
-
-#ifdef _MSC_VER
-# pragma warning(pop)
-#endif
--- a/fmt/format.h	Fri Jul 13 12:57:10 2018 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,3883 +0,0 @@
-/*
- Formatting library for C++
-
- Copyright (c) 2012 - 2016, Victor Zverovich
- All rights reserved.
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
-
- 1. Redistributions of source code must retain the above copyright notice, this
-    list of conditions and the following disclaimer.
- 2. Redistributions in binary form must reproduce the above copyright notice,
-    this list of conditions and the following disclaimer in the documentation
-    and/or other materials provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
- ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef FMT_FORMAT_H_
-#define FMT_FORMAT_H_
-
-#include <cassert>
-#include <clocale>
-#include <cmath>
-#include <cstdio>
-#include <cstring>
-#include <limits>
-#include <memory>
-#include <stdexcept>
-#include <string>
-#include <vector>
-#include <utility>
-
-#ifdef _SECURE_SCL
-# define FMT_SECURE_SCL _SECURE_SCL
-#else
-# define FMT_SECURE_SCL 0
-#endif
-
-#if FMT_SECURE_SCL
-# include <iterator>
-#endif
-
-#ifdef _MSC_VER
-# define FMT_MSC_VER _MSC_VER
-#else
-# define FMT_MSC_VER 0
-#endif
-
-#if FMT_MSC_VER && FMT_MSC_VER <= 1500
-typedef unsigned __int32 uint32_t;
-typedef unsigned __int64 uint64_t;
-typedef __int64          intmax_t;
-#else
-#include <stdint.h>
-#endif
-
-#if !defined(FMT_HEADER_ONLY) && defined(_WIN32)
-# ifdef FMT_EXPORT
-#  define FMT_API __declspec(dllexport)
-# elif defined(FMT_SHARED)
-#  define FMT_API __declspec(dllimport)
-# endif
-#endif
-#ifndef FMT_API
-# define FMT_API
-#endif
-
-#ifdef __GNUC__
-# define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-# define FMT_GCC_EXTENSION __extension__
-# if FMT_GCC_VERSION >= 406
-#  pragma GCC diagnostic push
-// Disable the warning about "long long" which is sometimes reported even
-// when using __extension__.
-#  pragma GCC diagnostic ignored "-Wlong-long"
-// Disable the warning about declaration shadowing because it affects too
-// many valid cases.
-#  pragma GCC diagnostic ignored "-Wshadow"
-// Disable the warning about implicit conversions that may change the sign of
-// an integer; silencing it otherwise would require many explicit casts.
-#  pragma GCC diagnostic ignored "-Wsign-conversion"
-# endif
-# if __cplusplus >= 201103L || defined __GXX_EXPERIMENTAL_CXX0X__
-#  define FMT_HAS_GXX_CXX11 1
-# endif
-#else
-# define FMT_GCC_EXTENSION
-#endif
-
-#if defined(__INTEL_COMPILER)
-# define FMT_ICC_VERSION __INTEL_COMPILER
-#elif defined(__ICL)
-# define FMT_ICC_VERSION __ICL
-#endif
-
-#if defined(__clang__) && !defined(FMT_ICC_VERSION)
-# pragma clang diagnostic push
-# pragma clang diagnostic ignored "-Wdocumentation-unknown-command"
-# pragma clang diagnostic ignored "-Wpadded"
-#endif
-
-#ifdef __GNUC_LIBSTD__
-# define FMT_GNUC_LIBSTD_VERSION (__GNUC_LIBSTD__ * 100 + __GNUC_LIBSTD_MINOR__)
-#endif
-
-#ifdef __has_feature
-# define FMT_HAS_FEATURE(x) __has_feature(x)
-#else
-# define FMT_HAS_FEATURE(x) 0
-#endif
-
-#ifdef __has_builtin
-# define FMT_HAS_BUILTIN(x) __has_builtin(x)
-#else
-# define FMT_HAS_BUILTIN(x) 0
-#endif
-
-#ifdef __has_cpp_attribute
-# define FMT_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
-#else
-# define FMT_HAS_CPP_ATTRIBUTE(x) 0
-#endif
-
-#ifndef FMT_USE_VARIADIC_TEMPLATES
-// Variadic templates are available in GCC since version 4.4
-// (http://gcc.gnu.org/projects/cxx0x.html) and in Visual C++
-// since version 2013.
-# define FMT_USE_VARIADIC_TEMPLATES \
-   (FMT_HAS_FEATURE(cxx_variadic_templates) || \
-       (FMT_GCC_VERSION >= 404 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1800)
-#endif
-
-#ifndef FMT_USE_RVALUE_REFERENCES
-// Don't use rvalue references when compiling with clang and an old libstdc++
-// as the latter doesn't provide std::move.
-# if defined(FMT_GNUC_LIBSTD_VERSION) && FMT_GNUC_LIBSTD_VERSION <= 402
-#  define FMT_USE_RVALUE_REFERENCES 0
-# else
-#  define FMT_USE_RVALUE_REFERENCES \
-    (FMT_HAS_FEATURE(cxx_rvalue_references) || \
-        (FMT_GCC_VERSION >= 403 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1600)
-# endif
-#endif
-
-#if FMT_USE_RVALUE_REFERENCES
-# include <utility>  // for std::move
-#endif
-
-// Check if exceptions are disabled.
-#if defined(__GNUC__) && !defined(__EXCEPTIONS)
-# define FMT_EXCEPTIONS 0
-#endif
-#if FMT_MSC_VER && !_HAS_EXCEPTIONS
-# define FMT_EXCEPTIONS 0
-#endif
-#ifndef FMT_EXCEPTIONS
-# define FMT_EXCEPTIONS 1
-#endif
-
-#ifndef FMT_THROW
-# if FMT_EXCEPTIONS
-#  define FMT_THROW(x) throw x
-# else
-#  define FMT_THROW(x) assert(false)
-# endif
-#endif
-
-// Define FMT_USE_NOEXCEPT to make fmt use noexcept (C++11 feature).
-#ifndef FMT_USE_NOEXCEPT
-# define FMT_USE_NOEXCEPT 0
-#endif
-
-#ifndef FMT_NOEXCEPT
-# if FMT_EXCEPTIONS
-#  if FMT_USE_NOEXCEPT || FMT_HAS_FEATURE(cxx_noexcept) || \
-    (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || \
-    FMT_MSC_VER >= 1900
-#   define FMT_NOEXCEPT noexcept
-#  else
-#   define FMT_NOEXCEPT throw()
-#  endif
-# else
-#  define FMT_NOEXCEPT
-# endif
-#endif
-
-#ifndef FMT_OVERRIDE
-# if FMT_USE_OVERRIDE || FMT_HAS_FEATURE(cxx_override) || \
-   (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || \
-   FMT_MSC_VER >= 1900
-#  define FMT_OVERRIDE override
-# else
-#  define FMT_OVERRIDE
-# endif
-#endif
-
-
-// A macro to disallow the copy constructor and operator= functions
-// This should be used in the private: declarations for a class
-#ifndef FMT_USE_DELETED_FUNCTIONS
-# define FMT_USE_DELETED_FUNCTIONS 0
-#endif
-
-#if FMT_USE_DELETED_FUNCTIONS || FMT_HAS_FEATURE(cxx_deleted_functions) || \
-  (FMT_GCC_VERSION >= 404 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1800
-# define FMT_DELETED_OR_UNDEFINED  = delete
-# define FMT_DISALLOW_COPY_AND_ASSIGN(TypeName) \
-    TypeName(const TypeName&) = delete; \
-    TypeName& operator=(const TypeName&) = delete
-#else
-# define FMT_DELETED_OR_UNDEFINED
-# define FMT_DISALLOW_COPY_AND_ASSIGN(TypeName) \
-    TypeName(const TypeName&); \
-    TypeName& operator=(const TypeName&)
-#endif
-
-#ifndef FMT_USE_USER_DEFINED_LITERALS
-// All compilers which support UDLs also support variadic templates. This
-// makes the fmt::literals implementation easier. However, an explicit check
-// for variadic templates is added here just in case.
-// For Intel's compiler both it and the system gcc/msc must support UDLs.
-# define FMT_USE_USER_DEFINED_LITERALS \
-   FMT_USE_VARIADIC_TEMPLATES && FMT_USE_RVALUE_REFERENCES && \
-   (FMT_HAS_FEATURE(cxx_user_literals) || \
-     (FMT_GCC_VERSION >= 407 && FMT_HAS_GXX_CXX11) || FMT_MSC_VER >= 1900) && \
-   (!defined(FMT_ICC_VERSION) || FMT_ICC_VERSION >= 1500)
-#endif
-
-#ifndef FMT_ASSERT
-# define FMT_ASSERT(condition, message) assert((condition) && message)
-#endif
-
-#if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__builtin_clz)
-# define FMT_BUILTIN_CLZ(n) __builtin_clz(n)
-#endif
-
-#if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__builtin_clzll)
-# define FMT_BUILTIN_CLZLL(n) __builtin_clzll(n)
-#endif
-
-// Some compilers masquerade as both MSVC and GCC-likes or
-// otherwise support __builtin_clz and __builtin_clzll, so
-// only define FMT_BUILTIN_CLZ using the MSVC intrinsics
-// if the clz and clzll builtins are not available.
-#if FMT_MSC_VER && !defined(FMT_BUILTIN_CLZLL)
-# include <intrin.h>  // _BitScanReverse, _BitScanReverse64
-
-namespace fmt {
-namespace internal {
-# pragma intrinsic(_BitScanReverse)
-inline uint32_t clz(uint32_t x) {
-  unsigned long r = 0;
-  _BitScanReverse(&r, x);
-
-  assert(x != 0);
-  // Static analysis complains about using uninitialized data
-  // "r", but the only way that can happen is if "x" is 0,
-  // which the callers guarantee to not happen.
-# pragma warning(suppress: 6102)
-  return 31 - r;
-}
-# define FMT_BUILTIN_CLZ(n) fmt::internal::clz(n)
-
-# ifdef _WIN64
-#  pragma intrinsic(_BitScanReverse64)
-# endif
-
-inline uint32_t clzll(uint64_t x) {
-  unsigned long r = 0;
-# ifdef _WIN64
-  _BitScanReverse64(&r, x);
-# else
-  // Scan the high 32 bits.
-  if (_BitScanReverse(&r, static_cast<uint32_t>(x >> 32)))
-    return 63 - (r + 32);
-
-  // Scan the low 32 bits.
-  _BitScanReverse(&r, static_cast<uint32_t>(x));
-# endif
-
-  assert(x != 0);
-  // Static analysis complains about using uninitialized data
-  // "r", but the only way that can happen is if "x" is 0,
-  // which the callers guarantee to not happen.
-# pragma warning(suppress: 6102)
-  return 63 - r;
-}
-# define FMT_BUILTIN_CLZLL(n) fmt::internal::clzll(n)
-}
-}
-#endif
-
-namespace fmt {
-namespace internal {
-struct DummyInt {
-  int data[2];
-  operator int() const { return 0; }
-};
-typedef std::numeric_limits<fmt::internal::DummyInt> FPUtil;
-
-// Dummy implementations of system functions such as signbit and ecvt called
-// if the latter are not available.
-inline DummyInt signbit(...) { return DummyInt(); }
-inline DummyInt _ecvt_s(...) { return DummyInt(); }
-inline DummyInt isinf(...) { return DummyInt(); }
-inline DummyInt _finite(...) { return DummyInt(); }
-inline DummyInt isnan(...) { return DummyInt(); }
-inline DummyInt _isnan(...) { return DummyInt(); }
-
-// A helper function to suppress bogus "conditional expression is constant"
-// warnings.
-template <typename T>
-inline T const_check(T value) { return value; }
-}
-}  // namespace fmt
-
-namespace std {
-// Standard permits specialization of std::numeric_limits. This specialization
-// is used to resolve ambiguity between isinf and std::isinf in glibc:
-// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48891
-// and the same for isnan and signbit.
-template <>
-class numeric_limits<fmt::internal::DummyInt> :
-    public std::numeric_limits<int> {
- public:
-  // Portable version of isinf.
-  template <typename T>
-  static bool isinfinity(T x) {
-    using namespace fmt::internal;
-    // The resolution "priority" is:
-    // isinf macro > std::isinf > ::isinf > fmt::internal::isinf
-    if (const_check(sizeof(isinf(x)) == sizeof(bool) ||
-                    sizeof(isinf(x)) == sizeof(int))) {
-      return isinf(x) != 0;
-    }
-    return !_finite(static_cast<double>(x));
-  }
-
-  // Portable version of isnan.
-  template <typename T>
-  static bool isnotanumber(T x) {
-    using namespace fmt::internal;
-    if (const_check(sizeof(isnan(x)) == sizeof(bool) ||
-                    sizeof(isnan(x)) == sizeof(int))) {
-      return isnan(x) != 0;
-    }
-    return _isnan(static_cast<double>(x)) != 0;
-  }
-
-  // Portable version of signbit.
-  static bool isnegative(double x) {
-    using namespace fmt::internal;
-    if (const_check(sizeof(signbit(x)) == sizeof(int)))
-      return signbit(x) != 0;
-    if (x < 0) return true;
-    if (!isnotanumber(x)) return false;
-    int dec = 0, sign = 0;
-    char buffer[2];  // The buffer size must be >= 2 or _ecvt_s will fail.
-    _ecvt_s(buffer, sizeof(buffer), x, 0, &dec, &sign);
-    return sign != 0;
-  }
-};
-}  // namespace std
-
-namespace fmt {
-
-// Fix the warning about long long on older versions of GCC
-// that don't support the diagnostic pragma.
-FMT_GCC_EXTENSION typedef long long LongLong;
-FMT_GCC_EXTENSION typedef unsigned long long ULongLong;
-
-#if FMT_USE_RVALUE_REFERENCES
-using std::move;
-#endif
-
-template <typename Char>
-class BasicWriter;
-
-typedef BasicWriter<char> Writer;
-typedef BasicWriter<wchar_t> WWriter;
-
-template <typename Char>
-class ArgFormatter;
-
-template <typename CharType,
-          typename ArgFormatter = fmt::ArgFormatter<CharType> >
-class BasicFormatter;
-
-/**
-  \rst
-  A string reference. It can be constructed from a C string or ``std::string``.
-
-  You can use one of the following typedefs for common character types:
-
-  +------------+-------------------------+
-  | Type       | Definition              |
-  +============+=========================+
-  | StringRef  | BasicStringRef<char>    |
-  +------------+-------------------------+
-  | WStringRef | BasicStringRef<wchar_t> |
-  +------------+-------------------------+
-
-  This class is most useful as a parameter type to allow passing
-  different types of strings to a function, for example::
-
-    template <typename... Args>
-    std::string format(StringRef format_str, const Args & ... args);
-
-    format("{}", 42);
-    format(std::string("{}"), 42);
-  \endrst
- */
-template <typename Char>
-class BasicStringRef {
- private:
-  const Char *data_;
-  std::size_t size_;
-
- public:
-  /** Constructs a string reference object from a C string and a size. */
-  BasicStringRef(const Char *s, std::size_t size) : data_(s), size_(size) {}
-
-  /**
-    \rst
-    Constructs a string reference object from a C string computing
-    the size with ``std::char_traits<Char>::length``.
-    \endrst
-   */
-  BasicStringRef(const Char *s)
-    : data_(s), size_(std::char_traits<Char>::length(s)) {}
-
-  /**
-    \rst
-    Constructs a string reference from an ``std::string`` object.
-    \endrst
-   */
-  BasicStringRef(const std::basic_string<Char> &s)
-  : data_(s.c_str()), size_(s.size()) {}
-
-  /**
-    \rst
-    Converts a string reference to an ``std::string`` object.
-    \endrst
-   */
-  std::basic_string<Char> to_string() const {
-    return std::basic_string<Char>(data_, size_);
-  }
-
-  /** Returns a pointer to the string data. */
-  const Char *data() const { return data_; }
-
-  /** Returns the string size. */
-  std::size_t size() const { return size_; }
-
-  // Lexicographically compare this string reference to other.
-  int compare(BasicStringRef other) const {
-    std::size_t size = size_ < other.size_ ? size_ : other.size_;
-    int result = std::char_traits<Char>::compare(data_, other.data_, size);
-    if (result == 0)
-      result = size_ == other.size_ ? 0 : (size_ < other.size_ ? -1 : 1);
-    return result;
-  }
-
-  friend bool operator==(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) == 0;
-  }
-  friend bool operator!=(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) != 0;
-  }
-  friend bool operator<(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) < 0;
-  }
-  friend bool operator<=(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) <= 0;
-  }
-  friend bool operator>(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) > 0;
-  }
-  friend bool operator>=(BasicStringRef lhs, BasicStringRef rhs) {
-    return lhs.compare(rhs) >= 0;
-  }
-};
-
-typedef BasicStringRef<char> StringRef;
-typedef BasicStringRef<wchar_t> WStringRef;
-
-/**
-  \rst
-  A reference to a null terminated string. It can be constructed from a C
-  string or ``std::string``.
-
-  You can use one of the following typedefs for common character types:
-
-  +-------------+--------------------------+
-  | Type        | Definition               |
-  +=============+==========================+
-  | CStringRef  | BasicCStringRef<char>    |
-  +-------------+--------------------------+
-  | WCStringRef | BasicCStringRef<wchar_t> |
-  +-------------+--------------------------+
-
-  This class is most useful as a parameter type to allow passing
-  different types of strings to a function, for example::
-
-    template <typename... Args>
-    std::string format(CStringRef format_str, const Args & ... args);
-
-    format("{}", 42);
-    format(std::string("{}"), 42);
-  \endrst
- */
-template <typename Char>
-class BasicCStringRef {
- private:
-  const Char *data_;
-
- public:
-  /** Constructs a string reference object from a C string. */
-  BasicCStringRef(const Char *s) : data_(s) {}
-
-  /**
-    \rst
-    Constructs a string reference from an ``std::string`` object.
-    \endrst
-   */
-  BasicCStringRef(const std::basic_string<Char> &s) : data_(s.c_str()) {}
-
-  /** Returns the pointer to a C string. */
-  const Char *c_str() const { return data_; }
-};
-
-typedef BasicCStringRef<char> CStringRef;
-typedef BasicCStringRef<wchar_t> WCStringRef;
-
-/** A formatting error such as invalid format string. */
-class FormatError : public std::runtime_error {
- public:
-  explicit FormatError(CStringRef message)
-  : std::runtime_error(message.c_str()) {}
-  ~FormatError() throw();
-};
-
-namespace internal {
-
-// MakeUnsigned<T>::Type gives an unsigned type corresponding to integer type T.
-template <typename T>
-struct MakeUnsigned { typedef T Type; };
-
-#define FMT_SPECIALIZE_MAKE_UNSIGNED(T, U) \
-  template <> \
-  struct MakeUnsigned<T> { typedef U Type; }
-
-FMT_SPECIALIZE_MAKE_UNSIGNED(char, unsigned char);
-FMT_SPECIALIZE_MAKE_UNSIGNED(signed char, unsigned char);
-FMT_SPECIALIZE_MAKE_UNSIGNED(short, unsigned short);
-FMT_SPECIALIZE_MAKE_UNSIGNED(int, unsigned);
-FMT_SPECIALIZE_MAKE_UNSIGNED(long, unsigned long);
-FMT_SPECIALIZE_MAKE_UNSIGNED(LongLong, ULongLong);
-
-// Casts nonnegative integer to unsigned.
-template <typename Int>
-inline typename MakeUnsigned<Int>::Type to_unsigned(Int value) {
-  FMT_ASSERT(value >= 0, "negative value");
-  return static_cast<typename MakeUnsigned<Int>::Type>(value);
-}
-
-// The number of characters to store in the MemoryBuffer object itself
-// to avoid dynamic memory allocation.
-enum { INLINE_BUFFER_SIZE = 500 };
-
-#if FMT_SECURE_SCL
-// Use checked iterator to avoid warnings on MSVC.
-template <typename T>
-inline stdext::checked_array_iterator<T*> make_ptr(T *ptr, std::size_t size) {
-  return stdext::checked_array_iterator<T*>(ptr, size);
-}
-#else
-template <typename T>
-inline T *make_ptr(T *ptr, std::size_t) { return ptr; }
-#endif
-}  // namespace internal
-
-/**
-  \rst
-  A buffer supporting a subset of ``std::vector``'s operations.
-  \endrst
- */
-template <typename T>
-class Buffer {
- private:
-  FMT_DISALLOW_COPY_AND_ASSIGN(Buffer);
-
- protected:
-  T *ptr_;
-  std::size_t size_;
-  std::size_t capacity_;
-
-  Buffer(T *ptr = 0, std::size_t capacity = 0)
-    : ptr_(ptr), size_(0), capacity_(capacity) {}
-
-  /**
-    \rst
-    Increases the buffer capacity to hold at least *size* elements updating
-    ``ptr_`` and ``capacity_``.
-    \endrst
-   */
-  virtual void grow(std::size_t size) = 0;
-
- public:
-  virtual ~Buffer() {}
-
-  /** Returns the size of this buffer. */
-  std::size_t size() const { return size_; }
-
-  /** Returns the capacity of this buffer. */
-  std::size_t capacity() const { return capacity_; }
-
-  /**
-    Resizes the buffer. If T is a POD type new elements may not be initialized.
-   */
-  void resize(std::size_t new_size) {
-    if (new_size > capacity_)
-      grow(new_size);
-    size_ = new_size;
-  }
-
-  /**
-    \rst
-    Reserves space to store at least *capacity* elements.
-    \endrst
-   */
-  void reserve(std::size_t capacity) {
-    if (capacity > capacity_)
-      grow(capacity);
-  }
-
-  void clear() FMT_NOEXCEPT { size_ = 0; }
-
-  void push_back(const T &value) {
-    if (size_ == capacity_)
-      grow(size_ + 1);
-    ptr_[size_++] = value;
-  }
-
-  /** Appends data to the end of the buffer. */
-  template <typename U>
-  void append(const U *begin, const U *end);
-
-  T &operator[](std::size_t index) { return ptr_[index]; }
-  const T &operator[](std::size_t index) const { return ptr_[index]; }
-};
-
-template <typename T>
-template <typename U>
-void Buffer<T>::append(const U *begin, const U *end) {
-  std::size_t new_size = size_ + internal::to_unsigned(end - begin);
-  if (new_size > capacity_)
-    grow(new_size);
-  std::uninitialized_copy(begin, end,
-                          internal::make_ptr(ptr_, capacity_) + size_);
-  size_ = new_size;
-}
-
-namespace internal {
-
-// A memory buffer for trivially copyable/constructible types with the first
-// SIZE elements stored in the object itself.
-template <typename T, std::size_t SIZE, typename Allocator = std::allocator<T> >
-class MemoryBuffer : private Allocator, public Buffer<T> {
- private:
-  T data_[SIZE];
-
-  // Deallocate memory allocated by the buffer.
-  void deallocate() {
-    if (this->ptr_ != data_) Allocator::deallocate(this->ptr_, this->capacity_);
-  }
-
- protected:
-  void grow(std::size_t size) FMT_OVERRIDE;
-
- public:
-  explicit MemoryBuffer(const Allocator &alloc = Allocator())
-      : Allocator(alloc), Buffer<T>(data_, SIZE) {}
-  ~MemoryBuffer() { deallocate(); }
-
-#if FMT_USE_RVALUE_REFERENCES
- private:
-  // Move data from other to this buffer.
-  void move(MemoryBuffer &other) {
-    Allocator &this_alloc = *this, &other_alloc = other;
-    this_alloc = std::move(other_alloc);
-    this->size_ = other.size_;
-    this->capacity_ = other.capacity_;
-    if (other.ptr_ == other.data_) {
-      this->ptr_ = data_;
-      std::uninitialized_copy(other.data_, other.data_ + this->size_,
-                              make_ptr(data_, this->capacity_));
-    } else {
-      this->ptr_ = other.ptr_;
-      // Set pointer to the inline array so that delete is not called
-      // when deallocating.
-      other.ptr_ = other.data_;
-    }
-  }
-
- public:
-  MemoryBuffer(MemoryBuffer &&other) {
-    move(other);
-  }
-
-  MemoryBuffer &operator=(MemoryBuffer &&other) {
-    assert(this != &other);
-    deallocate();
-    move(other);
-    return *this;
-  }
-#endif
-
-  // Returns a copy of the allocator associated with this buffer.
-  Allocator get_allocator() const { return *this; }
-};
-
-template <typename T, std::size_t SIZE, typename Allocator>
-void MemoryBuffer<T, SIZE, Allocator>::grow(std::size_t size) {
-  std::size_t new_capacity = this->capacity_ + this->capacity_ / 2;
-  if (size > new_capacity)
-      new_capacity = size;
-  T *new_ptr = this->allocate(new_capacity);
-  // The following code doesn't throw, so the raw pointer above doesn't leak.
-  std::uninitialized_copy(this->ptr_, this->ptr_ + this->size_,
-                          make_ptr(new_ptr, new_capacity));
-  std::size_t old_capacity = this->capacity_;
-  T *old_ptr = this->ptr_;
-  this->capacity_ = new_capacity;
-  this->ptr_ = new_ptr;
-  // deallocate may throw (at least in principle), but it doesn't matter since
-  // the buffer already uses the new storage and will deallocate it in case
-  // of exception.
-  if (old_ptr != data_)
-    Allocator::deallocate(old_ptr, old_capacity);
-}
-
-// A fixed-size buffer.
-template <typename Char>
-class FixedBuffer : public fmt::Buffer<Char> {
- public:
-  FixedBuffer(Char *array, std::size_t size) : fmt::Buffer<Char>(array, size) {}
-
- protected:
-  FMT_API void grow(std::size_t size);
-};
-
-template <typename Char>
-class BasicCharTraits {
- public:
-#if FMT_SECURE_SCL
-  typedef stdext::checked_array_iterator<Char*> CharPtr;
-#else
-  typedef Char *CharPtr;
-#endif
-  static Char cast(int value) { return static_cast<Char>(value); }
-};
-
-template <typename Char>
-class CharTraits;
-
-template <>
-class CharTraits<char> : public BasicCharTraits<char> {
- private:
-  // Conversion from wchar_t to char is not allowed.
-  static char convert(wchar_t);
-
- public:
-  static char convert(char value) { return value; }
-
-  // Formats a floating-point number.
-  template <typename T>
-  FMT_API static int format_float(char *buffer, std::size_t size,
-      const char *format, unsigned width, int precision, T value);
-};
-
-template <>
-class CharTraits<wchar_t> : public BasicCharTraits<wchar_t> {
- public:
-  static wchar_t convert(char value) { return value; }
-  static wchar_t convert(wchar_t value) { return value; }
-
-  template <typename T>
-  FMT_API static int format_float(wchar_t *buffer, std::size_t size,
-      const wchar_t *format, unsigned width, int precision, T value);
-};
-
-// Checks if a number is negative - used to avoid warnings.
-template <bool IsSigned>
-struct SignChecker {
-  template <typename T>
-  static bool is_negative(T value) { return value < 0; }
-};
-
-template <>
-struct SignChecker<false> {
-  template <typename T>
-  static bool is_negative(T) { return false; }
-};
-
-// Returns true if value is negative, false otherwise.
-// Same as (value < 0) but doesn't produce warnings if T is an unsigned type.
-template <typename T>
-inline bool is_negative(T value) {
-  return SignChecker<std::numeric_limits<T>::is_signed>::is_negative(value);
-}
-
-// Selects uint32_t if FitsIn32Bits is true, uint64_t otherwise.
-template <bool FitsIn32Bits>
-struct TypeSelector { typedef uint32_t Type; };
-
-template <>
-struct TypeSelector<false> { typedef uint64_t Type; };
-
-template <typename T>
-struct IntTraits {
-  // Smallest of uint32_t and uint64_t that is large enough to represent
-  // all values of T.
-  typedef typename
-    TypeSelector<std::numeric_limits<T>::digits <= 32>::Type MainType;
-};
-
-FMT_API void report_unknown_type(char code, const char *type);
-
-// Static data is placed in this class template to allow header-only
-// configuration.
-template <typename T = void>
-struct FMT_API BasicData {
-  static const uint32_t POWERS_OF_10_32[];
-  static const uint64_t POWERS_OF_10_64[];
-  static const char DIGITS[];
-};
-
-#ifndef FMT_USE_EXTERN_TEMPLATES
-// Clang doesn't have a feature check for extern templates so we check
-// for variadic templates which were introduced in the same version.
-# define FMT_USE_EXTERN_TEMPLATES (__clang__ && FMT_USE_VARIADIC_TEMPLATES)
-#endif
-
-#if FMT_USE_EXTERN_TEMPLATES && !defined(FMT_HEADER_ONLY)
-extern template struct BasicData<void>;
-#endif
-
-typedef BasicData<> Data;
-
-#ifdef FMT_BUILTIN_CLZLL
-// Returns the number of decimal digits in n. Leading zeros are not counted
-// except for n == 0 in which case count_digits returns 1.
-inline unsigned count_digits(uint64_t n) {
-  // Based on http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
-  // and the benchmark https://github.com/localvoid/cxx-benchmark-count-digits.
-  int t = (64 - FMT_BUILTIN_CLZLL(n | 1)) * 1233 >> 12;
-  return to_unsigned(t) - (n < Data::POWERS_OF_10_64[t]) + 1;
-}
-#else
-// Fallback version of count_digits used when __builtin_clz is not available.
-inline unsigned count_digits(uint64_t n) {
-  unsigned count = 1;
-  for (;;) {
-    // Integer division is slow so do it for a group of four digits instead
-    // of for every digit. The idea comes from the talk by Alexandrescu
-    // "Three Optimization Tips for C++". See speed-test for a comparison.
-    if (n < 10) return count;
-    if (n < 100) return count + 1;
-    if (n < 1000) return count + 2;
-    if (n < 10000) return count + 3;
-    n /= 10000u;
-    count += 4;
-  }
-}
-#endif
-
-#ifdef FMT_BUILTIN_CLZ
-// Optional version of count_digits for better performance on 32-bit platforms.
-inline unsigned count_digits(uint32_t n) {
-  int t = (32 - FMT_BUILTIN_CLZ(n | 1)) * 1233 >> 12;
-  return to_unsigned(t) - (n < Data::POWERS_OF_10_32[t]) + 1;
-}
-#endif
-
-// A functor that doesn't add a thousands separator.
-struct NoThousandsSep {
-  template <typename Char>
-  void operator()(Char *) {}
-};
-
-// A functor that adds a thousands separator.
-class ThousandsSep {
- private:
-  fmt::StringRef sep_;
-
-  // Index of a decimal digit with the least significant digit having index 0.
-  unsigned digit_index_;
-
- public:
-  explicit ThousandsSep(fmt::StringRef sep) : sep_(sep), digit_index_(0) {}
-
-  template <typename Char>
-  void operator()(Char *&buffer) {
-    if (++digit_index_ % 3 != 0)
-      return;
-    buffer -= sep_.size();
-    std::uninitialized_copy(sep_.data(), sep_.data() + sep_.size(),
-                            internal::make_ptr(buffer, sep_.size()));
-  }
-};
-
-// Formats a decimal unsigned integer value writing into buffer.
-// thousands_sep is a functor that is called after writing each char to
-// add a thousands separator if necessary.
-template <typename UInt, typename Char, typename ThousandsSep>
-inline void format_decimal(Char *buffer, UInt value, unsigned num_digits,
-                           ThousandsSep thousands_sep) {
-  buffer += num_digits;
-  while (value >= 100) {
-    // Integer division is slow so do it for a group of two digits instead
-    // of for every digit. The idea comes from the talk by Alexandrescu
-    // "Three Optimization Tips for C++". See speed-test for a comparison.
-    unsigned index = static_cast<unsigned>((value % 100) * 2);
-    value /= 100;
-    *--buffer = Data::DIGITS[index + 1];
-    thousands_sep(buffer);
-    *--buffer = Data::DIGITS[index];
-    thousands_sep(buffer);
-  }
-  if (value < 10) {
-    *--buffer = static_cast<char>('0' + value);
-    return;
-  }
-  unsigned index = static_cast<unsigned>(value * 2);
-  *--buffer = Data::DIGITS[index + 1];
-  thousands_sep(buffer);
-  *--buffer = Data::DIGITS[index];
-}
-
-template <typename UInt, typename Char>
-inline void format_decimal(Char *buffer, UInt value, unsigned num_digits) {
-  return format_decimal(buffer, value, num_digits, NoThousandsSep());
-}
-
-#ifndef _WIN32
-# define FMT_USE_WINDOWS_H 0
-#elif !defined(FMT_USE_WINDOWS_H)
-# define FMT_USE_WINDOWS_H 1
-#endif
-
-// Define FMT_USE_WINDOWS_H to 0 to disable use of windows.h.
-// All the functionality that relies on it will be disabled too.
-#if FMT_USE_WINDOWS_H
-// A converter from UTF-8 to UTF-16.
-// It is only provided for Windows since other systems support UTF-8 natively.
-class UTF8ToUTF16 {
- private:
-  MemoryBuffer<wchar_t, INLINE_BUFFER_SIZE> buffer_;
-
- public:
-  FMT_API explicit UTF8ToUTF16(StringRef s);
-  operator WStringRef() const { return WStringRef(&buffer_[0], size()); }
-  size_t size() const { return buffer_.size() - 1; }
-  const wchar_t *c_str() const { return &buffer_[0]; }
-  std::wstring str() const { return std::wstring(&buffer_[0], size()); }
-};
-
-// A converter from UTF-16 to UTF-8.
-// It is only provided for Windows since other systems support UTF-8 natively.
-class UTF16ToUTF8 {
- private:
-  MemoryBuffer<char, INLINE_BUFFER_SIZE> buffer_;
-
- public:
-  UTF16ToUTF8() {}
-  FMT_API explicit UTF16ToUTF8(WStringRef s);
-  operator StringRef() const { return StringRef(&buffer_[0], size()); }
-  size_t size() const { return buffer_.size() - 1; }
-  const char *c_str() const { return &buffer_[0]; }
-  std::string str() const { return std::string(&buffer_[0], size()); }
-
-  // Performs conversion returning a system error code instead of
-  // throwing exception on conversion error. This method may still throw
-  // in case of memory allocation error.
-  FMT_API int convert(WStringRef s);
-};
-
-FMT_API void format_windows_error(fmt::Writer &out, int error_code,
-                                  fmt::StringRef message) FMT_NOEXCEPT;
-#endif
-
-FMT_API void format_system_error(fmt::Writer &out, int error_code,
-                                 fmt::StringRef message) FMT_NOEXCEPT;
-
-// A formatting argument value.
-struct Value {
-  template <typename Char>
-  struct StringValue {
-    const Char *value;
-    std::size_t size;
-  };
-
-  typedef void (*FormatFunc)(
-      void *formatter, const void *arg, void *format_str_ptr);
-
-  struct CustomValue {
-    const void *value;
-    FormatFunc format;
-  };
-
-  union {
-    int int_value;
-    unsigned uint_value;
-    LongLong long_long_value;
-    ULongLong ulong_long_value;
-    double double_value;
-    long double long_double_value;
-    const void *pointer;
-    StringValue<char> string;
-    StringValue<signed char> sstring;
-    StringValue<unsigned char> ustring;
-    StringValue<wchar_t> wstring;
-    CustomValue custom;
-  };
-
-  enum Type {
-    NONE, NAMED_ARG,
-    // Integer types should go first,
-    INT, UINT, LONG_LONG, ULONG_LONG, BOOL, CHAR, LAST_INTEGER_TYPE = CHAR,
-    // followed by floating-point types.
-    DOUBLE, LONG_DOUBLE, LAST_NUMERIC_TYPE = LONG_DOUBLE,
-    CSTRING, STRING, WSTRING, POINTER, CUSTOM
-  };
-};
-
-// A formatting argument. It is a trivially copyable/constructible type to
-// allow storage in internal::MemoryBuffer.
-struct Arg : Value {
-  Type type;
-};
-
-template <typename Char>
-struct NamedArg;
-
-template <typename T = void>
-struct Null {};
-
-// A helper class template to enable or disable overloads taking wide
-// characters and strings in MakeValue.
-template <typename T, typename Char>
-struct WCharHelper {
-  typedef Null<T> Supported;
-  typedef T Unsupported;
-};
-
-template <typename T>
-struct WCharHelper<T, wchar_t> {
-  typedef T Supported;
-  typedef Null<T> Unsupported;
-};
-
-typedef char Yes[1];
-typedef char No[2];
-
-template <typename T>
-T &get();
-
-// These are non-members to workaround an overload resolution bug in bcc32.
-Yes &convert(fmt::ULongLong);
-No &convert(...);
-
-template<typename T, bool ENABLE_CONVERSION>
-struct ConvertToIntImpl {
-  enum { value = ENABLE_CONVERSION };
-};
-
-template<typename T, bool ENABLE_CONVERSION>
-struct ConvertToIntImpl2 {
-  enum { value = false };
-};
-
-template<typename T>
-struct ConvertToIntImpl2<T, true> {
-  enum {
-    // Don't convert numeric types.
-    value = ConvertToIntImpl<T, !std::numeric_limits<T>::is_specialized>::value
-  };
-};
-
-template<typename T>
-struct ConvertToInt {
-  enum { enable_conversion = sizeof(convert(get<T>())) == sizeof(Yes) };
-  enum { value = ConvertToIntImpl2<T, enable_conversion>::value };
-};
-
-#define FMT_DISABLE_CONVERSION_TO_INT(Type) \
-  template <> \
-  struct ConvertToInt<Type> {  enum { value = 0 }; }
-
-// Silence warnings about convering float to int.
-FMT_DISABLE_CONVERSION_TO_INT(float);
-FMT_DISABLE_CONVERSION_TO_INT(double);
-FMT_DISABLE_CONVERSION_TO_INT(long double);
-
-template<bool B, class T = void>
-struct EnableIf {};
-
-template<class T>
-struct EnableIf<true, T> { typedef T type; };
-
-template<bool B, class T, class F>
-struct Conditional { typedef T type; };
-
-template<class T, class F>
-struct Conditional<false, T, F> { typedef F type; };
-
-// For bcc32 which doesn't understand ! in template arguments.
-template<bool>
-struct Not { enum { value = 0 }; };
-
-template<>
-struct Not<false> { enum { value = 1 }; };
-
-template<typename T, T> struct LConvCheck {
-  LConvCheck(int) {}
-};
-
-// Returns the thousands separator for the current locale.
-// We check if ``lconv`` contains ``thousands_sep`` because on Android
-// ``lconv`` is stubbed as an empty struct.
-template <typename LConv>
-inline StringRef thousands_sep(
-    LConv *lc, LConvCheck<char *LConv::*, &LConv::thousands_sep> = 0) {
-  return lc->thousands_sep;
-}
-
-inline fmt::StringRef thousands_sep(...) { return ""; }
-
-// Makes an Arg object from any type.
-template <typename Formatter>
-class MakeValue : public Arg {
- public:
-  typedef typename Formatter::Char Char;
-
- private:
-  // The following two methods are private to disallow formatting of
-  // arbitrary pointers. If you want to output a pointer cast it to
-  // "void *" or "const void *". In particular, this forbids formatting
-  // of "[const] volatile char *" which is printed as bool by iostreams.
-  // Do not implement!
-  template <typename T>
-  MakeValue(const T *value);
-  template <typename T>
-  MakeValue(T *value);
-
-  // The following methods are private to disallow formatting of wide
-  // characters and strings into narrow strings as in
-  //   fmt::format("{}", L"test");
-  // To fix this, use a wide format string: fmt::format(L"{}", L"test").
-#if !FMT_MSC_VER || defined(_NATIVE_WCHAR_T_DEFINED)
-  MakeValue(typename WCharHelper<wchar_t, Char>::Unsupported);
-#endif
-  MakeValue(typename WCharHelper<wchar_t *, Char>::Unsupported);
-  MakeValue(typename WCharHelper<const wchar_t *, Char>::Unsupported);
-  MakeValue(typename WCharHelper<const std::wstring &, Char>::Unsupported);
-  MakeValue(typename WCharHelper<WStringRef, Char>::Unsupported);
-
-  void set_string(StringRef str) {
-    string.value = str.data();
-    string.size = str.size();
-  }
-
-  void set_string(WStringRef str) {
-    wstring.value = str.data();
-    wstring.size = str.size();
-  }
-
-  // Formats an argument of a custom type, such as a user-defined class.
-  template <typename T>
-  static void format_custom_arg(
-      void *formatter, const void *arg, void *format_str_ptr) {
-    format(*static_cast<Formatter*>(formatter),
-           *static_cast<const Char**>(format_str_ptr),
-           *static_cast<const T*>(arg));
-  }
-
- public:
-  MakeValue() {}
-
-#define FMT_MAKE_VALUE_(Type, field, TYPE, rhs) \
-  MakeValue(Type value) { field = rhs; } \
-  static uint64_t type(Type) { return Arg::TYPE; }
-
-#define FMT_MAKE_VALUE(Type, field, TYPE) \
-  FMT_MAKE_VALUE_(Type, field, TYPE, value)
-
-  FMT_MAKE_VALUE(bool, int_value, BOOL)
-  FMT_MAKE_VALUE(short, int_value, INT)
-  FMT_MAKE_VALUE(unsigned short, uint_value, UINT)
-  FMT_MAKE_VALUE(int, int_value, INT)
-  FMT_MAKE_VALUE(unsigned, uint_value, UINT)
-
-  MakeValue(long value) {
-    // To minimize the number of types we need to deal with, long is
-    // translated either to int or to long long depending on its size.
-    if (const_check(sizeof(long) == sizeof(int)))
-      int_value = static_cast<int>(value);
-    else
-      long_long_value = value;
-  }
-  static uint64_t type(long) {
-    return sizeof(long) == sizeof(int) ? Arg::INT : Arg::LONG_LONG;
-  }
-
-  MakeValue(unsigned long value) {
-    if (const_check(sizeof(unsigned long) == sizeof(unsigned)))
-      uint_value = static_cast<unsigned>(value);
-    else
-      ulong_long_value = value;
-  }
-  static uint64_t type(unsigned long) {
-    return sizeof(unsigned long) == sizeof(unsigned) ?
-          Arg::UINT : Arg::ULONG_LONG;
-  }
-
-  FMT_MAKE_VALUE(LongLong, long_long_value, LONG_LONG)
-  FMT_MAKE_VALUE(ULongLong, ulong_long_value, ULONG_LONG)
-  FMT_MAKE_VALUE(float, double_value, DOUBLE)
-  FMT_MAKE_VALUE(double, double_value, DOUBLE)
-  FMT_MAKE_VALUE(long double, long_double_value, LONG_DOUBLE)
-  FMT_MAKE_VALUE(signed char, int_value, INT)
-  FMT_MAKE_VALUE(unsigned char, uint_value, UINT)
-  FMT_MAKE_VALUE(char, int_value, CHAR)
-
-#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
-  MakeValue(typename WCharHelper<wchar_t, Char>::Supported value) {
-    int_value = value;
-  }
-  static uint64_t type(wchar_t) { return Arg::CHAR; }
-#endif
-
-#define FMT_MAKE_STR_VALUE(Type, TYPE) \
-  MakeValue(Type value) { set_string(value); } \
-  static uint64_t type(Type) { return Arg::TYPE; }
-
-  FMT_MAKE_VALUE(char *, string.value, CSTRING)
-  FMT_MAKE_VALUE(const char *, string.value, CSTRING)
-  FMT_MAKE_VALUE(signed char *, sstring.value, CSTRING)
-  FMT_MAKE_VALUE(const signed char *, sstring.value, CSTRING)
-  FMT_MAKE_VALUE(unsigned char *, ustring.value, CSTRING)
-  FMT_MAKE_VALUE(const unsigned char *, ustring.value, CSTRING)
-  FMT_MAKE_STR_VALUE(const std::string &, STRING)
-  FMT_MAKE_STR_VALUE(StringRef, STRING)
-  FMT_MAKE_VALUE_(CStringRef, string.value, CSTRING, value.c_str())
-
-#define FMT_MAKE_WSTR_VALUE(Type, TYPE) \
-  MakeValue(typename WCharHelper<Type, Char>::Supported value) { \
-    set_string(value); \
-  } \
-  static uint64_t type(Type) { return Arg::TYPE; }
-
-  FMT_MAKE_WSTR_VALUE(wchar_t *, WSTRING)
-  FMT_MAKE_WSTR_VALUE(const wchar_t *, WSTRING)
-  FMT_MAKE_WSTR_VALUE(const std::wstring &, WSTRING)
-  FMT_MAKE_WSTR_VALUE(WStringRef, WSTRING)
-
-  FMT_MAKE_VALUE(void *, pointer, POINTER)
-  FMT_MAKE_VALUE(const void *, pointer, POINTER)
-
-  template <typename T>
-  MakeValue(const T &value,
-            typename EnableIf<Not<
-              ConvertToInt<T>::value>::value, int>::type = 0) {
-    custom.value = &value;
-    custom.format = &format_custom_arg<T>;
-  }
-
-  template <typename T>
-  MakeValue(const T &value,
-            typename EnableIf<ConvertToInt<T>::value, int>::type = 0) {
-    int_value = value;
-  }
-
-  template <typename T>
-  static uint64_t type(const T &) {
-    return ConvertToInt<T>::value ? Arg::INT : Arg::CUSTOM;
-  }
-
-  // Additional template param `Char_` is needed here because make_type always
-  // uses char.
-  template <typename Char_>
-  MakeValue(const NamedArg<Char_> &value) { pointer = &value; }
-
-  template <typename Char_>
-  static uint64_t type(const NamedArg<Char_> &) { return Arg::NAMED_ARG; }
-};
-
-template <typename Formatter>
-class MakeArg : public Arg {
-public:
-  MakeArg() {
-    type = Arg::NONE;
-  }
-
-  template <typename T>
-  MakeArg(const T &value)
-  : Arg(MakeValue<Formatter>(value)) {
-    type = static_cast<Arg::Type>(MakeValue<Formatter>::type(value));
-  }
-};
-
-template <typename Char>
-struct NamedArg : Arg {
-  BasicStringRef<Char> name;
-
-  template <typename T>
-  NamedArg(BasicStringRef<Char> argname, const T &value)
-  : Arg(MakeArg< BasicFormatter<Char> >(value)), name(argname) {}
-};
-
-class RuntimeError : public std::runtime_error {
- protected:
-  RuntimeError() : std::runtime_error("") {}
-  ~RuntimeError() throw();
-};
-
-template <typename Char>
-class PrintfArgFormatter;
-
-template <typename Char>
-class ArgMap;
-}  // namespace internal
-
-/** An argument list. */
-class ArgList {
- private:
-  // To reduce compiled code size per formatting function call, types of first
-  // MAX_PACKED_ARGS arguments are passed in the types_ field.
-  uint64_t types_;
-  union {
-    // If the number of arguments is less than MAX_PACKED_ARGS, the argument
-    // values are stored in values_, otherwise they are stored in args_.
-    // This is done to reduce compiled code size as storing larger objects
-    // may require more code (at least on x86-64) even if the same amount of
-    // data is actually copied to stack. It saves ~10% on the bloat test.
-    const internal::Value *values_;
-    const internal::Arg *args_;
-  };
-
-  internal::Arg::Type type(unsigned index) const {
-    unsigned shift = index * 4;
-    uint64_t mask = 0xf;
-    return static_cast<internal::Arg::Type>(
-          (types_ & (mask << shift)) >> shift);
-  }
-
-  template <typename Char>
-  friend class internal::ArgMap;
-
- public:
-  // Maximum number of arguments with packed types.
-  enum { MAX_PACKED_ARGS = 16 };
-
-  ArgList() : types_(0) {}
-
-  ArgList(ULongLong types, const internal::Value *values)
-  : types_(types), values_(values) {}
-  ArgList(ULongLong types, const internal::Arg *args)
-  : types_(types), args_(args) {}
-
-  /** Returns the argument at specified index. */
-  internal::Arg operator[](unsigned index) const {
-    using internal::Arg;
-    Arg arg;
-    bool use_values = type(MAX_PACKED_ARGS - 1) == Arg::NONE;
-    if (index < MAX_PACKED_ARGS) {
-      Arg::Type arg_type = type(index);
-      internal::Value &val = arg;
-      if (arg_type != Arg::NONE)
-        val = use_values ? values_[index] : args_[index];
-      arg.type = arg_type;
-      return arg;
-    }
-    if (use_values) {
-      // The index is greater than the number of arguments that can be stored
-      // in values, so return a "none" argument.
-      arg.type = Arg::NONE;
-      return arg;
-    }
-    for (unsigned i = MAX_PACKED_ARGS; i <= index; ++i) {
-      if (args_[i].type == Arg::NONE)
-        return args_[i];
-    }
-    return args_[index];
-  }
-};
-
-#define FMT_DISPATCH(call) static_cast<Impl*>(this)->call
-
-/**
-  \rst
-  An argument visitor based on the `curiously recurring template pattern
-  <http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern>`_.
-
-  To use `~fmt::ArgVisitor` define a subclass that implements some or all of the
-  visit methods with the same signatures as the methods in `~fmt::ArgVisitor`,
-  for example, `~fmt::ArgVisitor::visit_int()`.
-  Pass the subclass as the *Impl* template parameter. Then calling
-  `~fmt::ArgVisitor::visit` for some argument will dispatch to a visit method
-  specific to the argument type. For example, if the argument type is
-  ``double`` then the `~fmt::ArgVisitor::visit_double()` method of a subclass
-  will be called. If the subclass doesn't contain a method with this signature,
-  then a corresponding method of `~fmt::ArgVisitor` will be called.
-
-  **Example**::
-
-    class MyArgVisitor : public fmt::ArgVisitor<MyArgVisitor, void> {
-     public:
-      void visit_int(int value) { fmt::print("{}", value); }
-      void visit_double(double value) { fmt::print("{}", value ); }
-    };
-  \endrst
- */
-template <typename Impl, typename Result>
-class ArgVisitor {
- private:
-  typedef internal::Arg Arg;
-
- public:
-  void report_unhandled_arg() {}
-
-  Result visit_unhandled_arg() {
-    FMT_DISPATCH(report_unhandled_arg());
-    return Result();
-  }
-
-  /** Visits an ``int`` argument. **/
-  Result visit_int(int value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits a ``long long`` argument. **/
-  Result visit_long_long(LongLong value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits an ``unsigned`` argument. **/
-  Result visit_uint(unsigned value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits an ``unsigned long long`` argument. **/
-  Result visit_ulong_long(ULongLong value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits a ``bool`` argument. **/
-  Result visit_bool(bool value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits a ``char`` or ``wchar_t`` argument. **/
-  Result visit_char(int value) {
-    return FMT_DISPATCH(visit_any_int(value));
-  }
-
-  /** Visits an argument of any integral type. **/
-  template <typename T>
-  Result visit_any_int(T) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits a ``double`` argument. **/
-  Result visit_double(double value) {
-    return FMT_DISPATCH(visit_any_double(value));
-  }
-
-  /** Visits a ``long double`` argument. **/
-  Result visit_long_double(long double value) {
-    return FMT_DISPATCH(visit_any_double(value));
-  }
-
-  /** Visits a ``double`` or ``long double`` argument. **/
-  template <typename T>
-  Result visit_any_double(T) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits a null-terminated C string (``const char *``) argument. **/
-  Result visit_cstring(const char *) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits a string argument. **/
-  Result visit_string(Arg::StringValue<char>) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits a wide string argument. **/
-  Result visit_wstring(Arg::StringValue<wchar_t>) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits a pointer argument. **/
-  Result visit_pointer(const void *) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /** Visits an argument of a custom (user-defined) type. **/
-  Result visit_custom(Arg::CustomValue) {
-    return FMT_DISPATCH(visit_unhandled_arg());
-  }
-
-  /**
-    \rst
-    Visits an argument dispatching to the appropriate visit method based on
-    the argument type. For example, if the argument type is ``double`` then
-    the `~fmt::ArgVisitor::visit_double()` method of the *Impl* class will be
-    called.
-    \endrst
-   */
-  Result visit(const Arg &arg) {
-    switch (arg.type) {
-    case Arg::NONE:
-    case Arg::NAMED_ARG:
-      FMT_ASSERT(false, "invalid argument type");
-      break;
-    case Arg::INT:
-      return FMT_DISPATCH(visit_int(arg.int_value));
-    case Arg::UINT:
-      return FMT_DISPATCH(visit_uint(arg.uint_value));
-    case Arg::LONG_LONG:
-      return FMT_DISPATCH(visit_long_long(arg.long_long_value));
-    case Arg::ULONG_LONG:
-      return FMT_DISPATCH(visit_ulong_long(arg.ulong_long_value));
-    case Arg::BOOL:
-      return FMT_DISPATCH(visit_bool(arg.int_value != 0));
-    case Arg::CHAR:
-      return FMT_DISPATCH(visit_char(arg.int_value));
-    case Arg::DOUBLE:
-      return FMT_DISPATCH(visit_double(arg.double_value));
-    case Arg::LONG_DOUBLE:
-      return FMT_DISPATCH(visit_long_double(arg.long_double_value));
-    case Arg::CSTRING:
-      return FMT_DISPATCH(visit_cstring(arg.string.value));
-    case Arg::STRING:
-      return FMT_DISPATCH(visit_string(arg.string));
-    case Arg::WSTRING:
-      return FMT_DISPATCH(visit_wstring(arg.wstring));
-    case Arg::POINTER:
-      return FMT_DISPATCH(visit_pointer(arg.pointer));
-    case Arg::CUSTOM:
-      return FMT_DISPATCH(visit_custom(arg.custom));
-    }
-    return Result();
-  }
-};
-
-enum Alignment {
-  ALIGN_DEFAULT, ALIGN_LEFT, ALIGN_RIGHT, ALIGN_CENTER, ALIGN_NUMERIC
-};
-
-// Flags.
-enum {
-  SIGN_FLAG = 1, PLUS_FLAG = 2, MINUS_FLAG = 4, HASH_FLAG = 8,
-  CHAR_FLAG = 0x10  // Argument has char type - used in error reporting.
-};
-
-// An empty format specifier.
-struct EmptySpec {};
-
-// A type specifier.
-template <char TYPE>
-struct TypeSpec : EmptySpec {
-  Alignment align() const { return ALIGN_DEFAULT; }
-  unsigned width() const { return 0; }
-  int precision() const { return -1; }
-  bool flag(unsigned) const { return false; }
-  char type() const { return TYPE; }
-  char fill() const { return ' '; }
-};
-
-// A width specifier.
-struct WidthSpec {
-  unsigned width_;
-  // Fill is always wchar_t and cast to char if necessary to avoid having
-  // two specialization of WidthSpec and its subclasses.
-  wchar_t fill_;
-
-  WidthSpec(unsigned width, wchar_t fill) : width_(width), fill_(fill) {}
-
-  unsigned width() const { return width_; }
-  wchar_t fill() const { return fill_; }
-};
-
-// An alignment specifier.
-struct AlignSpec : WidthSpec {
-  Alignment align_;
-
-  AlignSpec(unsigned width, wchar_t fill, Alignment align = ALIGN_DEFAULT)
-  : WidthSpec(width, fill), align_(align) {}
-
-  Alignment align() const { return align_; }
-
-  int precision() const { return -1; }
-};
-
-// An alignment and type specifier.
-template <char TYPE>
-struct AlignTypeSpec : AlignSpec {
-  AlignTypeSpec(unsigned width, wchar_t fill) : AlignSpec(width, fill) {}
-
-  bool flag(unsigned) const { return false; }
-  char type() const { return TYPE; }
-};
-
-// A full format specifier.
-struct FormatSpec : AlignSpec {
-  unsigned flags_;
-  int precision_;
-  char type_;
-
-  FormatSpec(
-    unsigned width = 0, char type = 0, wchar_t fill = ' ')
-  : AlignSpec(width, fill), flags_(0), precision_(-1), type_(type) {}
-
-  bool flag(unsigned f) const { return (flags_ & f) != 0; }
-  int precision() const { return precision_; }
-  char type() const { return type_; }
-};
-
-// An integer format specifier.
-template <typename T, typename SpecT = TypeSpec<0>, typename Char = char>
-class IntFormatSpec : public SpecT {
- private:
-  T value_;
-
- public:
-  IntFormatSpec(T val, const SpecT &spec = SpecT())
-  : SpecT(spec), value_(val) {}
-
-  T value() const { return value_; }
-};
-
-// A string format specifier.
-template <typename Char>
-class StrFormatSpec : public AlignSpec {
- private:
-  const Char *str_;
-
- public:
-  template <typename FillChar>
-  StrFormatSpec(const Char *str, unsigned width, FillChar fill)
-  : AlignSpec(width, fill), str_(str) {
-    internal::CharTraits<Char>::convert(FillChar());
-  }
-
-  const Char *str() const { return str_; }
-};
-
-/**
-  Returns an integer format specifier to format the value in base 2.
- */
-IntFormatSpec<int, TypeSpec<'b'> > bin(int value);
-
-/**
-  Returns an integer format specifier to format the value in base 8.
- */
-IntFormatSpec<int, TypeSpec<'o'> > oct(int value);
-
-/**
-  Returns an integer format specifier to format the value in base 16 using
-  lower-case letters for the digits above 9.
- */
-IntFormatSpec<int, TypeSpec<'x'> > hex(int value);
-
-/**
-  Returns an integer formatter format specifier to format in base 16 using
-  upper-case letters for the digits above 9.
- */
-IntFormatSpec<int, TypeSpec<'X'> > hexu(int value);
-
-/**
-  \rst
-  Returns an integer format specifier to pad the formatted argument with the
-  fill character to the specified width using the default (right) numeric
-  alignment.
-
-  **Example**::
-
-    MemoryWriter out;
-    out << pad(hex(0xcafe), 8, '0');
-    // out.str() == "0000cafe"
-
-  \endrst
- */
-template <char TYPE_CODE, typename Char>
-IntFormatSpec<int, AlignTypeSpec<TYPE_CODE>, Char> pad(
-    int value, unsigned width, Char fill = ' ');
-
-#define FMT_DEFINE_INT_FORMATTERS(TYPE) \
-inline IntFormatSpec<TYPE, TypeSpec<'b'> > bin(TYPE value) { \
-  return IntFormatSpec<TYPE, TypeSpec<'b'> >(value, TypeSpec<'b'>()); \
-} \
- \
-inline IntFormatSpec<TYPE, TypeSpec<'o'> > oct(TYPE value) { \
-  return IntFormatSpec<TYPE, TypeSpec<'o'> >(value, TypeSpec<'o'>()); \
-} \
- \
-inline IntFormatSpec<TYPE, TypeSpec<'x'> > hex(TYPE value) { \
-  return IntFormatSpec<TYPE, TypeSpec<'x'> >(value, TypeSpec<'x'>()); \
-} \
- \
-inline IntFormatSpec<TYPE, TypeSpec<'X'> > hexu(TYPE value) { \
-  return IntFormatSpec<TYPE, TypeSpec<'X'> >(value, TypeSpec<'X'>()); \
-} \
- \
-template <char TYPE_CODE> \
-inline IntFormatSpec<TYPE, AlignTypeSpec<TYPE_CODE> > pad( \
-    IntFormatSpec<TYPE, TypeSpec<TYPE_CODE> > f, unsigned width) { \
-  return IntFormatSpec<TYPE, AlignTypeSpec<TYPE_CODE> >( \
-      f.value(), AlignTypeSpec<TYPE_CODE>(width, ' ')); \
-} \
- \
-/* For compatibility with older compilers we provide two overloads for pad, */ \
-/* one that takes a fill character and one that doesn't. In the future this */ \
-/* can be replaced with one overload making the template argument Char      */ \
-/* default to char (C++11). */ \
-template <char TYPE_CODE, typename Char> \
-inline IntFormatSpec<TYPE, AlignTypeSpec<TYPE_CODE>, Char> pad( \
-    IntFormatSpec<TYPE, TypeSpec<TYPE_CODE>, Char> f, \
-    unsigned width, Char fill) { \
-  return IntFormatSpec<TYPE, AlignTypeSpec<TYPE_CODE>, Char>( \
-      f.value(), AlignTypeSpec<TYPE_CODE>(width, fill)); \
-} \
- \
-inline IntFormatSpec<TYPE, AlignTypeSpec<0> > pad( \
-    TYPE value, unsigned width) { \
-  return IntFormatSpec<TYPE, AlignTypeSpec<0> >( \
-      value, AlignTypeSpec<0>(width, ' ')); \
-} \
- \
-template <typename Char> \
-inline IntFormatSpec<TYPE, AlignTypeSpec<0>, Char> pad( \
-   TYPE value, unsigned width, Char fill) { \
- return IntFormatSpec<TYPE, AlignTypeSpec<0>, Char>( \
-     value, AlignTypeSpec<0>(width, fill)); \
-}
-
-FMT_DEFINE_INT_FORMATTERS(int)
-FMT_DEFINE_INT_FORMATTERS(long)
-FMT_DEFINE_INT_FORMATTERS(unsigned)
-FMT_DEFINE_INT_FORMATTERS(unsigned long)
-FMT_DEFINE_INT_FORMATTERS(LongLong)
-FMT_DEFINE_INT_FORMATTERS(ULongLong)
-
-/**
-  \rst
-  Returns a string formatter that pads the formatted argument with the fill
-  character to the specified width using the default (left) string alignment.
-
-  **Example**::
-
-    std::string s = str(MemoryWriter() << pad("abc", 8));
-    // s == "abc     "
-
-  \endrst
- */
-template <typename Char>
-inline StrFormatSpec<Char> pad(
-    const Char *str, unsigned width, Char fill = ' ') {
-  return StrFormatSpec<Char>(str, width, fill);
-}
-
-inline StrFormatSpec<wchar_t> pad(
-    const wchar_t *str, unsigned width, char fill = ' ') {
-  return StrFormatSpec<wchar_t>(str, width, fill);
-}
-
-namespace internal {
-
-template <typename Char>
-class ArgMap {
- private:
-  typedef std::vector<
-    std::pair<fmt::BasicStringRef<Char>, internal::Arg> > MapType;
-  typedef typename MapType::value_type Pair;
-
-  MapType map_;
-
- public:
-  FMT_API void init(const ArgList &args);
-
-  const internal::Arg* find(const fmt::BasicStringRef<Char> &name) const {
-    // The list is unsorted, so just return the first matching name.
-    for (typename MapType::const_iterator it = map_.begin(), end = map_.end();
-         it != end; ++it) {
-      if (it->first == name)
-        return &it->second;
-    }
-    return 0;
-  }
-};
-
-template <typename Impl, typename Char>
-class ArgFormatterBase : public ArgVisitor<Impl, void> {
- private:
-  BasicWriter<Char> &writer_;
-  FormatSpec &spec_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(ArgFormatterBase);
-
-  void write_pointer(const void *p) {
-    spec_.flags_ = HASH_FLAG;
-    spec_.type_ = 'x';
-    writer_.write_int(reinterpret_cast<uintptr_t>(p), spec_);
-  }
-
- protected:
-  BasicWriter<Char> &writer() { return writer_; }
-  FormatSpec &spec() { return spec_; }
-
-  void write(bool value) {
-    const char *str_value = value ? "true" : "false";
-    Arg::StringValue<char> str = { str_value, std::strlen(str_value) };
-    writer_.write_str(str, spec_);
-  }
-
-  void write(const char *value) {
-    Arg::StringValue<char> str = {value, value != 0 ? std::strlen(value) : 0};
-    writer_.write_str(str, spec_);
-  }
-
- public:
-  ArgFormatterBase(BasicWriter<Char> &w, FormatSpec &s)
-  : writer_(w), spec_(s) {}
-
-  template <typename T>
-  void visit_any_int(T value) { writer_.write_int(value, spec_); }
-
-  template <typename T>
-  void visit_any_double(T value) { writer_.write_double(value, spec_); }
-
-  void visit_bool(bool value) {
-    if (spec_.type_)
-      return visit_any_int(value);
-    write(value);
-  }
-
-  void visit_char(int value) {
-    if (spec_.type_ && spec_.type_ != 'c') {
-      spec_.flags_ |= CHAR_FLAG;
-      writer_.write_int(value, spec_);
-      return;
-    }
-    if (spec_.align_ == ALIGN_NUMERIC || spec_.flags_ != 0)
-      FMT_THROW(FormatError("invalid format specifier for char"));
-    typedef typename BasicWriter<Char>::CharPtr CharPtr;
-    Char fill = internal::CharTraits<Char>::cast(spec_.fill());
-    CharPtr out = CharPtr();
-    const unsigned CHAR_SIZE = 1;
-    if (spec_.width_ > CHAR_SIZE) {
-      out = writer_.grow_buffer(spec_.width_);
-      if (spec_.align_ == ALIGN_RIGHT) {
-        std::uninitialized_fill_n(out, spec_.width_ - CHAR_SIZE, fill);
-        out += spec_.width_ - CHAR_SIZE;
-      } else if (spec_.align_ == ALIGN_CENTER) {
-        out = writer_.fill_padding(out, spec_.width_,
-                                   internal::const_check(CHAR_SIZE), fill);
-      } else {
-        std::uninitialized_fill_n(out + CHAR_SIZE,
-                                  spec_.width_ - CHAR_SIZE, fill);
-      }
-    } else {
-      out = writer_.grow_buffer(CHAR_SIZE);
-    }
-    *out = internal::CharTraits<Char>::cast(value);
-  }
-
-  void visit_cstring(const char *value) {
-    if (spec_.type_ == 'p')
-      return write_pointer(value);
-    write(value);
-  }
-
-  void visit_string(Arg::StringValue<char> value) {
-    writer_.write_str(value, spec_);
-  }
-
-  using ArgVisitor<Impl, void>::visit_wstring;
-
-  void visit_wstring(Arg::StringValue<Char> value) {
-    writer_.write_str(value, spec_);
-  }
-
-  void visit_pointer(const void *value) {
-    if (spec_.type_ && spec_.type_ != 'p')
-      report_unknown_type(spec_.type_, "pointer");
-    write_pointer(value);
-  }
-};
-
-class FormatterBase {
- private:
-  ArgList args_;
-  int next_arg_index_;
-
-  // Returns the argument with specified index.
-  FMT_API Arg do_get_arg(unsigned arg_index, const char *&error);
-
- protected:
-  const ArgList &args() const { return args_; }
-
-  explicit FormatterBase(const ArgList &args) {
-    args_ = args;
-    next_arg_index_ = 0;
-  }
-
-  // Returns the next argument.
-  Arg next_arg(const char *&error) {
-    if (next_arg_index_ >= 0)
-      return do_get_arg(internal::to_unsigned(next_arg_index_++), error);
-    error = "cannot switch from manual to automatic argument indexing";
-    return Arg();
-  }
-
-  // Checks if manual indexing is used and returns the argument with
-  // specified index.
-  Arg get_arg(unsigned arg_index, const char *&error) {
-    return check_no_auto_index(error) ? do_get_arg(arg_index, error) : Arg();
-  }
-
-  bool check_no_auto_index(const char *&error) {
-    if (next_arg_index_ > 0) {
-      error = "cannot switch from automatic to manual argument indexing";
-      return false;
-    }
-    next_arg_index_ = -1;
-    return true;
-  }
-
-  template <typename Char>
-  void write(BasicWriter<Char> &w, const Char *start, const Char *end) {
-    if (start != end)
-      w << BasicStringRef<Char>(start, internal::to_unsigned(end - start));
-  }
-};
-
-// A printf formatter.
-template <typename Char>
-class PrintfFormatter : private FormatterBase {
- private:
-  void parse_flags(FormatSpec &spec, const Char *&s);
-
-  // Returns the argument with specified index or, if arg_index is equal
-  // to the maximum unsigned value, the next argument.
-  Arg get_arg(const Char *s,
-      unsigned arg_index = (std::numeric_limits<unsigned>::max)());
-
-  // Parses argument index, flags and width and returns the argument index.
-  unsigned parse_header(const Char *&s, FormatSpec &spec);
-
- public:
-  explicit PrintfFormatter(const ArgList &args) : FormatterBase(args) {}
-  FMT_API void format(BasicWriter<Char> &writer,
-                      BasicCStringRef<Char> format_str);
-};
-}  // namespace internal
-
-/**
-  \rst
-  An argument formatter based on the `curiously recurring template pattern
-  <http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern>`_.
-
-  To use `~fmt::BasicArgFormatter` define a subclass that implements some or
-  all of the visit methods with the same signatures as the methods in
-  `~fmt::ArgVisitor`, for example, `~fmt::ArgVisitor::visit_int()`.
-  Pass the subclass as the *Impl* template parameter. When a formatting
-  function processes an argument, it will dispatch to a visit method
-  specific to the argument type. For example, if the argument type is
-  ``double`` then the `~fmt::ArgVisitor::visit_double()` method of a subclass
-  will be called. If the subclass doesn't contain a method with this signature,
-  then a corresponding method of `~fmt::BasicArgFormatter` or its superclass
-  will be called.
-  \endrst
- */
-template <typename Impl, typename Char>
-class BasicArgFormatter : public internal::ArgFormatterBase<Impl, Char> {
- private:
-  BasicFormatter<Char, Impl> &formatter_;
-  const Char *format_;
-
- public:
-  /**
-    \rst
-    Constructs an argument formatter object.
-    *formatter* is a reference to the main formatter object, *spec* contains
-    format specifier information for standard argument types, and *fmt* points
-    to the part of the format string being parsed for custom argument types.
-    \endrst
-   */
-  BasicArgFormatter(BasicFormatter<Char, Impl> &formatter,
-                    FormatSpec &spec, const Char *fmt)
-  : internal::ArgFormatterBase<Impl, Char>(formatter.writer(), spec),
-    formatter_(formatter), format_(fmt) {}
-
-  /** Formats argument of a custom (user-defined) type. */
-  void visit_custom(internal::Arg::CustomValue c) {
-    c.format(&formatter_, c.value, &format_);
-  }
-};
-
-/** The default argument formatter. */
-template <typename Char>
-class ArgFormatter : public BasicArgFormatter<ArgFormatter<Char>, Char> {
- public:
-  /** Constructs an argument formatter object. */
-  ArgFormatter(BasicFormatter<Char> &formatter,
-               FormatSpec &spec, const Char *fmt)
-  : BasicArgFormatter<ArgFormatter<Char>, Char>(formatter, spec, fmt) {}
-};
-
-/** This template formats data and writes the output to a writer. */
-template <typename CharType, typename ArgFormatter>
-class BasicFormatter : private internal::FormatterBase {
- public:
-  /** The character type for the output. */
-  typedef CharType Char;
-
- private:
-  BasicWriter<Char> &writer_;
-  internal::ArgMap<Char> map_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(BasicFormatter);
-
-  using internal::FormatterBase::get_arg;
-
-  // Checks if manual indexing is used and returns the argument with
-  // specified name.
-  internal::Arg get_arg(BasicStringRef<Char> arg_name, const char *&error);
-
-  // Parses argument index and returns corresponding argument.
-  internal::Arg parse_arg_index(const Char *&s);
-
-  // Parses argument name and returns corresponding argument.
-  internal::Arg parse_arg_name(const Char *&s);
-
- public:
-  /**
-   \rst
-   Constructs a ``BasicFormatter`` object. References to the arguments and
-   the writer are stored in the formatter object so make sure they have
-   appropriate lifetimes.
-   \endrst
-   */
-  BasicFormatter(const ArgList &args, BasicWriter<Char> &w)
-    : internal::FormatterBase(args), writer_(w) {}
-
-  /** Returns a reference to the writer associated with this formatter. */
-  BasicWriter<Char> &writer() { return writer_; }
-
-  /** Formats stored arguments and writes the output to the writer. */
-  void format(BasicCStringRef<Char> format_str);
-
-  // Formats a single argument and advances format_str, a format string pointer.
-  const Char *format(const Char *&format_str, const internal::Arg &arg);
-};
-
-// Generates a comma-separated list with results of applying f to
-// numbers 0..n-1.
-# define FMT_GEN(n, f) FMT_GEN##n(f)
-# define FMT_GEN1(f)  f(0)
-# define FMT_GEN2(f)  FMT_GEN1(f),  f(1)
-# define FMT_GEN3(f)  FMT_GEN2(f),  f(2)
-# define FMT_GEN4(f)  FMT_GEN3(f),  f(3)
-# define FMT_GEN5(f)  FMT_GEN4(f),  f(4)
-# define FMT_GEN6(f)  FMT_GEN5(f),  f(5)
-# define FMT_GEN7(f)  FMT_GEN6(f),  f(6)
-# define FMT_GEN8(f)  FMT_GEN7(f),  f(7)
-# define FMT_GEN9(f)  FMT_GEN8(f),  f(8)
-# define FMT_GEN10(f) FMT_GEN9(f),  f(9)
-# define FMT_GEN11(f) FMT_GEN10(f), f(10)
-# define FMT_GEN12(f) FMT_GEN11(f), f(11)
-# define FMT_GEN13(f) FMT_GEN12(f), f(12)
-# define FMT_GEN14(f) FMT_GEN13(f), f(13)
-# define FMT_GEN15(f) FMT_GEN14(f), f(14)
-
-namespace internal {
-inline uint64_t make_type() { return 0; }
-
-template <typename T>
-inline uint64_t make_type(const T &arg) {
-  return MakeValue< BasicFormatter<char> >::type(arg);
-}
-
-template <unsigned N, bool/*IsPacked*/= (N < ArgList::MAX_PACKED_ARGS)>
-struct ArgArray;
-
-template <unsigned N>
-struct ArgArray<N, true/*IsPacked*/> {
-  typedef Value Type[N > 0 ? N : 1];
-
-  template <typename Formatter, typename T>
-  static Value make(const T &value) {
-#ifdef __clang__
-    Value result = MakeValue<Formatter>(value);
-    // Workaround a bug in Apple LLVM version 4.2 (clang-425.0.28) of clang:
-    // https://github.com/fmtlib/fmt/issues/276
-    (void)result.custom.format;
-    return result;
-#else
-    return MakeValue<Formatter>(value);
-#endif
-  }
-};
-
-template <unsigned N>
-struct ArgArray<N, false/*IsPacked*/> {
-  typedef Arg Type[N + 1]; // +1 for the list end Arg::NONE
-
-  template <typename Formatter, typename T>
-  static Arg make(const T &value) { return MakeArg<Formatter>(value); }
-};
-
-#if FMT_USE_VARIADIC_TEMPLATES
-template <typename Arg, typename... Args>
-inline uint64_t make_type(const Arg &first, const Args & ... tail) {
-  return make_type(first) | (make_type(tail...) << 4);
-}
-
-#else
-
-struct ArgType {
-  uint64_t type;
-
-  ArgType() : type(0) {}
-
-  template <typename T>
-  ArgType(const T &arg) : type(make_type(arg)) {}
-};
-
-# define FMT_ARG_TYPE_DEFAULT(n) ArgType t##n = ArgType()
-
-inline uint64_t make_type(FMT_GEN15(FMT_ARG_TYPE_DEFAULT)) {
-  return t0.type | (t1.type << 4) | (t2.type << 8) | (t3.type << 12) |
-      (t4.type << 16) | (t5.type << 20) | (t6.type << 24) | (t7.type << 28) |
-      (t8.type << 32) | (t9.type << 36) | (t10.type << 40) | (t11.type << 44) |
-      (t12.type << 48) | (t13.type << 52) | (t14.type << 56);
-}
-#endif
-}  // namespace internal
-
-# define FMT_MAKE_TEMPLATE_ARG(n) typename T##n
-# define FMT_MAKE_ARG_TYPE(n) T##n
-# define FMT_MAKE_ARG(n) const T##n &v##n
-# define FMT_ASSIGN_char(n) \
-  arr[n] = fmt::internal::MakeValue< fmt::BasicFormatter<char> >(v##n)
-# define FMT_ASSIGN_wchar_t(n) \
-  arr[n] = fmt::internal::MakeValue< fmt::BasicFormatter<wchar_t> >(v##n)
-
-#if FMT_USE_VARIADIC_TEMPLATES
-// Defines a variadic function returning void.
-# define FMT_VARIADIC_VOID(func, arg_type) \
-  template <typename... Args> \
-  void func(arg_type arg0, const Args & ... args) { \
-    typedef fmt::internal::ArgArray<sizeof...(Args)> ArgArray; \
-    typename ArgArray::Type array{ \
-      ArgArray::template make<fmt::BasicFormatter<Char> >(args)...}; \
-    func(arg0, fmt::ArgList(fmt::internal::make_type(args...), array)); \
-  }
-
-// Defines a variadic constructor.
-# define FMT_VARIADIC_CTOR(ctor, func, arg0_type, arg1_type) \
-  template <typename... Args> \
-  ctor(arg0_type arg0, arg1_type arg1, const Args & ... args) { \
-    typedef fmt::internal::ArgArray<sizeof...(Args)> ArgArray; \
-    typename ArgArray::Type array{ \
-      ArgArray::template make<fmt::BasicFormatter<Char> >(args)...}; \
-    func(arg0, arg1, fmt::ArgList(fmt::internal::make_type(args...), array)); \
-  }
-
-#else
-
-# define FMT_MAKE_REF(n) \
-  fmt::internal::MakeValue< fmt::BasicFormatter<Char> >(v##n)
-# define FMT_MAKE_REF2(n) v##n
-
-// Defines a wrapper for a function taking one argument of type arg_type
-// and n additional arguments of arbitrary types.
-# define FMT_WRAP1(func, arg_type, n) \
-  template <FMT_GEN(n, FMT_MAKE_TEMPLATE_ARG)> \
-  inline void func(arg_type arg1, FMT_GEN(n, FMT_MAKE_ARG)) { \
-    const fmt::internal::ArgArray<n>::Type array = {FMT_GEN(n, FMT_MAKE_REF)}; \
-    func(arg1, fmt::ArgList( \
-      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), array)); \
-  }
-
-// Emulates a variadic function returning void on a pre-C++11 compiler.
-# define FMT_VARIADIC_VOID(func, arg_type) \
-  inline void func(arg_type arg) { func(arg, fmt::ArgList()); } \
-  FMT_WRAP1(func, arg_type, 1) FMT_WRAP1(func, arg_type, 2) \
-  FMT_WRAP1(func, arg_type, 3) FMT_WRAP1(func, arg_type, 4) \
-  FMT_WRAP1(func, arg_type, 5) FMT_WRAP1(func, arg_type, 6) \
-  FMT_WRAP1(func, arg_type, 7) FMT_WRAP1(func, arg_type, 8) \
-  FMT_WRAP1(func, arg_type, 9) FMT_WRAP1(func, arg_type, 10)
-
-# define FMT_CTOR(ctor, func, arg0_type, arg1_type, n) \
-  template <FMT_GEN(n, FMT_MAKE_TEMPLATE_ARG)> \
-  ctor(arg0_type arg0, arg1_type arg1, FMT_GEN(n, FMT_MAKE_ARG)) { \
-    const fmt::internal::ArgArray<n>::Type array = {FMT_GEN(n, FMT_MAKE_REF)}; \
-    func(arg0, arg1, fmt::ArgList( \
-      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), array)); \
-  }
-
-// Emulates a variadic constructor on a pre-C++11 compiler.
-# define FMT_VARIADIC_CTOR(ctor, func, arg0_type, arg1_type) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 1) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 2) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 3) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 4) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 5) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 6) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 7) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 8) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 9) \
-  FMT_CTOR(ctor, func, arg0_type, arg1_type, 10)
-#endif
-
-// Generates a comma-separated list with results of applying f to pairs
-// (argument, index).
-#define FMT_FOR_EACH1(f, x0) f(x0, 0)
-#define FMT_FOR_EACH2(f, x0, x1) \
-  FMT_FOR_EACH1(f, x0), f(x1, 1)
-#define FMT_FOR_EACH3(f, x0, x1, x2) \
-  FMT_FOR_EACH2(f, x0 ,x1), f(x2, 2)
-#define FMT_FOR_EACH4(f, x0, x1, x2, x3) \
-  FMT_FOR_EACH3(f, x0, x1, x2), f(x3, 3)
-#define FMT_FOR_EACH5(f, x0, x1, x2, x3, x4) \
-  FMT_FOR_EACH4(f, x0, x1, x2, x3), f(x4, 4)
-#define FMT_FOR_EACH6(f, x0, x1, x2, x3, x4, x5) \
-  FMT_FOR_EACH5(f, x0, x1, x2, x3, x4), f(x5, 5)
-#define FMT_FOR_EACH7(f, x0, x1, x2, x3, x4, x5, x6) \
-  FMT_FOR_EACH6(f, x0, x1, x2, x3, x4, x5), f(x6, 6)
-#define FMT_FOR_EACH8(f, x0, x1, x2, x3, x4, x5, x6, x7) \
-  FMT_FOR_EACH7(f, x0, x1, x2, x3, x4, x5, x6), f(x7, 7)
-#define FMT_FOR_EACH9(f, x0, x1, x2, x3, x4, x5, x6, x7, x8) \
-  FMT_FOR_EACH8(f, x0, x1, x2, x3, x4, x5, x6, x7), f(x8, 8)
-#define FMT_FOR_EACH10(f, x0, x1, x2, x3, x4, x5, x6, x7, x8, x9) \
-  FMT_FOR_EACH9(f, x0, x1, x2, x3, x4, x5, x6, x7, x8), f(x9, 9)
-
-/**
- An error returned by an operating system or a language runtime,
- for example a file opening error.
-*/
-class SystemError : public internal::RuntimeError {
- private:
-  void init(int err_code, CStringRef format_str, ArgList args);
-
- protected:
-  int error_code_;
-
-  typedef char Char;  // For FMT_VARIADIC_CTOR.
-
-  SystemError() {}
-
- public:
-  /**
-   \rst
-   Constructs a :class:`fmt::SystemError` object with the description
-   of the form
-
-   .. parsed-literal::
-     *<message>*: *<system-message>*
-
-   where *<message>* is the formatted message and *<system-message>* is
-   the system message corresponding to the error code.
-   *error_code* is a system error code as given by ``errno``.
-   If *error_code* is not a valid error code such as -1, the system message
-   may look like "Unknown error -1" and is platform-dependent.
-
-   **Example**::
-
-     // This throws a SystemError with the description
-     //   cannot open file 'madeup': No such file or directory
-     // or similar (system message may vary).
-     const char *filename = "madeup";
-     std::FILE *file = std::fopen(filename, "r");
-     if (!file)
-       throw fmt::SystemError(errno, "cannot open file '{}'", filename);
-   \endrst
-  */
-  SystemError(int error_code, CStringRef message) {
-    init(error_code, message, ArgList());
-  }
-  FMT_VARIADIC_CTOR(SystemError, init, int, CStringRef)
-
-  ~SystemError() throw();
-
-  int error_code() const { return error_code_; }
-};
-
-/**
-  \rst
-  This template provides operations for formatting and writing data into
-  a character stream. The output is stored in a buffer provided by a subclass
-  such as :class:`fmt::BasicMemoryWriter`.
-
-  You can use one of the following typedefs for common character types:
-
-  +---------+----------------------+
-  | Type    | Definition           |
-  +=========+======================+
-  | Writer  | BasicWriter<char>    |
-  +---------+----------------------+
-  | WWriter | BasicWriter<wchar_t> |
-  +---------+----------------------+
-
-  \endrst
- */
-template <typename Char>
-class BasicWriter {
- private:
-  // Output buffer.
-  Buffer<Char> &buffer_;
-
-  FMT_DISALLOW_COPY_AND_ASSIGN(BasicWriter);
-
-  typedef typename internal::CharTraits<Char>::CharPtr CharPtr;
-
-#if FMT_SECURE_SCL
-  // Returns pointer value.
-  static Char *get(CharPtr p) { return p.base(); }
-#else
-  static Char *get(Char *p) { return p; }
-#endif
-
-  // Fills the padding around the content and returns the pointer to the
-  // content area.
-  static CharPtr fill_padding(CharPtr buffer,
-      unsigned total_size, std::size_t content_size, wchar_t fill);
-
-  // Grows the buffer by n characters and returns a pointer to the newly
-  // allocated area.
-  CharPtr grow_buffer(std::size_t n) {
-    std::size_t size = buffer_.size();
-    buffer_.resize(size + n);
-    return internal::make_ptr(&buffer_[size], n);
-  }
-
-  // Writes an unsigned decimal integer.
-  template <typename UInt>
-  Char *write_unsigned_decimal(UInt value, unsigned prefix_size = 0) {
-    unsigned num_digits = internal::count_digits(value);
-    Char *ptr = get(grow_buffer(prefix_size + num_digits));
-    internal::format_decimal(ptr + prefix_size, value, num_digits);
-    return ptr;
-  }
-
-  // Writes a decimal integer.
-  template <typename Int>
-  void write_decimal(Int value) {
-    typedef typename internal::IntTraits<Int>::MainType MainType;
-    MainType abs_value = static_cast<MainType>(value);
-    if (internal::is_negative(value)) {
-      abs_value = 0 - abs_value;
-      *write_unsigned_decimal(abs_value, 1) = '-';
-    } else {
-      write_unsigned_decimal(abs_value, 0);
-    }
-  }
-
-  // Prepare a buffer for integer formatting.
-  CharPtr prepare_int_buffer(unsigned num_digits,
-      const EmptySpec &, const char *prefix, unsigned prefix_size) {
-    unsigned size = prefix_size + num_digits;
-    CharPtr p = grow_buffer(size);
-    std::uninitialized_copy(prefix, prefix + prefix_size, p);
-    return p + size - 1;
-  }
-
-  template <typename Spec>
-  CharPtr prepare_int_buffer(unsigned num_digits,
-    const Spec &spec, const char *prefix, unsigned prefix_size);
-
-  // Formats an integer.
-  template <typename T, typename Spec>
-  void write_int(T value, Spec spec);
-
-  // Formats a floating-point number (double or long double).
-  template <typename T>
-  void write_double(T value, const FormatSpec &spec);
-
-  // Writes a formatted string.
-  template <typename StrChar>
-  CharPtr write_str(const StrChar *s, std::size_t size, const AlignSpec &spec);
-
-  template <typename StrChar>
-  void write_str(const internal::Arg::StringValue<StrChar> &str,
-                 const FormatSpec &spec);
-
-  // This following methods are private to disallow writing wide characters
-  // and strings to a char stream. If you want to print a wide string as a
-  // pointer as std::ostream does, cast it to const void*.
-  // Do not implement!
-  void operator<<(typename internal::WCharHelper<wchar_t, Char>::Unsupported);
-  void operator<<(
-      typename internal::WCharHelper<const wchar_t *, Char>::Unsupported);
-
-  // Appends floating-point length specifier to the format string.
-  // The second argument is only used for overload resolution.
-  void append_float_length(Char *&format_ptr, long double) {
-    *format_ptr++ = 'L';
-  }
-
-  template<typename T>
-  void append_float_length(Char *&, T) {}
-
-  template <typename Impl, typename Char_>
-  friend class internal::ArgFormatterBase;
-
-  friend class internal::PrintfArgFormatter<Char>;
-
- protected:
-  /**
-    Constructs a ``BasicWriter`` object.
-   */
-  explicit BasicWriter(Buffer<Char> &b) : buffer_(b) {}
-
- public:
-  /**
-    \rst
-    Destroys a ``BasicWriter`` object.
-    \endrst
-   */
-  virtual ~BasicWriter() {}
-
-  /**
-    Returns the total number of characters written.
-   */
-  std::size_t size() const { return buffer_.size(); }
-
-  /**
-    Returns a pointer to the output buffer content. No terminating null
-    character is appended.
-   */
-  const Char *data() const FMT_NOEXCEPT { return &buffer_[0]; }
-
-  /**
-    Returns a pointer to the output buffer content with terminating null
-    character appended.
-   */
-  const Char *c_str() const {
-    std::size_t size = buffer_.size();
-    buffer_.reserve(size + 1);
-    buffer_[size] = '\0';
-    return &buffer_[0];
-  }
-
-  /**
-    \rst
-    Returns the content of the output buffer as an `std::string`.
-    \endrst
-   */
-  std::basic_string<Char> str() const {
-    return std::basic_string<Char>(&buffer_[0], buffer_.size());
-  }
-
-  /**
-    \rst
-    Writes formatted data.
-
-    *args* is an argument list representing arbitrary arguments.
-
-    **Example**::
-
-       MemoryWriter out;
-       out.write("Current point:\n");
-       out.write("({:+f}, {:+f})", -3.14, 3.14);
-
-    This will write the following output to the ``out`` object:
-
-    .. code-block:: none
-
-       Current point:
-       (-3.140000, +3.140000)
-
-    The output can be accessed using :func:`data()`, :func:`c_str` or
-    :func:`str` methods.
-
-    See also :ref:`syntax`.
-    \endrst
-   */
-  void write(BasicCStringRef<Char> format, ArgList args) {
-    BasicFormatter<Char>(args, *this).format(format);
-  }
-  FMT_VARIADIC_VOID(write, BasicCStringRef<Char>)
-
-  BasicWriter &operator<<(int value) {
-    write_decimal(value);
-    return *this;
-  }
-  BasicWriter &operator<<(unsigned value) {
-    return *this << IntFormatSpec<unsigned>(value);
-  }
-  BasicWriter &operator<<(long value) {
-    write_decimal(value);
-    return *this;
-  }
-  BasicWriter &operator<<(unsigned long value) {
-    return *this << IntFormatSpec<unsigned long>(value);
-  }
-  BasicWriter &operator<<(LongLong value) {
-    write_decimal(value);
-    return *this;
-  }
-
-  /**
-    \rst
-    Formats *value* and writes it to the stream.
-    \endrst
-   */
-  BasicWriter &operator<<(ULongLong value) {
-    return *this << IntFormatSpec<ULongLong>(value);
-  }
-
-  BasicWriter &operator<<(double value) {
-    write_double(value, FormatSpec());
-    return *this;
-  }
-
-  /**
-    \rst
-    Formats *value* using the general format for floating-point numbers
-    (``'g'``) and writes it to the stream.
-    \endrst
-   */
-  BasicWriter &operator<<(long double value) {
-    write_double(value, FormatSpec());
-    return *this;
-  }
-
-  /**
-    Writes a character to the stream.
-   */
-  BasicWriter &operator<<(char value) {
-    buffer_.push_back(value);
-    return *this;
-  }
-
-  BasicWriter &operator<<(
-      typename internal::WCharHelper<wchar_t, Char>::Supported value) {
-    buffer_.push_back(value);
-    return *this;
-  }
-
-  /**
-    \rst
-    Writes *value* to the stream.
-    \endrst
-   */
-  BasicWriter &operator<<(fmt::BasicStringRef<Char> value) {
-    const Char *str = value.data();
-    buffer_.append(str, str + value.size());
-    return *this;
-  }
-
-  BasicWriter &operator<<(
-      typename internal::WCharHelper<StringRef, Char>::Supported value) {
-    const char *str = value.data();
-    buffer_.append(str, str + value.size());
-    return *this;
-  }
-
-  template <typename T, typename Spec, typename FillChar>
-  BasicWriter &operator<<(IntFormatSpec<T, Spec, FillChar> spec) {
-    internal::CharTraits<Char>::convert(FillChar());
-    write_int(spec.value(), spec);
-    return *this;
-  }
-
-  template <typename StrChar>
-  BasicWriter &operator<<(const StrFormatSpec<StrChar> &spec) {
-    const StrChar *s = spec.str();
-    write_str(s, std::char_traits<Char>::length(s), spec);
-    return *this;
-  }
-
-  void clear() FMT_NOEXCEPT { buffer_.clear(); }
-
-  Buffer<Char> &buffer() FMT_NOEXCEPT { return buffer_; }
-};
-
-template <typename Char>
-template <typename StrChar>
-typename BasicWriter<Char>::CharPtr BasicWriter<Char>::write_str(
-      const StrChar *s, std::size_t size, const AlignSpec &spec) {
-  CharPtr out = CharPtr();
-  if (spec.width() > size) {
-    out = grow_buffer(spec.width());
-    Char fill = internal::CharTraits<Char>::cast(spec.fill());
-    if (spec.align() == ALIGN_RIGHT) {
-      std::uninitialized_fill_n(out, spec.width() - size, fill);
-      out += spec.width() - size;
-    } else if (spec.align() == ALIGN_CENTER) {
-      out = fill_padding(out, spec.width(), size, fill);
-    } else {
-      std::uninitialized_fill_n(out + size, spec.width() - size, fill);
-    }
-  } else {
-    out = grow_buffer(size);
-  }
-  std::uninitialized_copy(s, s + size, out);
-  return out;
-}
-
-template <typename Char>
-template <typename StrChar>
-void BasicWriter<Char>::write_str(
-    const internal::Arg::StringValue<StrChar> &s, const FormatSpec &spec) {
-  // Check if StrChar is convertible to Char.
-  internal::CharTraits<Char>::convert(StrChar());
-  if (spec.type_ && spec.type_ != 's')
-    internal::report_unknown_type(spec.type_, "string");
-  const StrChar *str_value = s.value;
-  std::size_t str_size = s.size;
-  if (str_size == 0) {
-    if (!str_value) {
-      FMT_THROW(FormatError("string pointer is null"));
-    }
-  }
-  std::size_t precision = static_cast<std::size_t>(spec.precision_);
-  if (spec.precision_ >= 0 && precision < str_size)
-    str_size = precision;
-  write_str(str_value, str_size, spec);
-}
-
-template <typename Char>
-typename BasicWriter<Char>::CharPtr
-  BasicWriter<Char>::fill_padding(
-    CharPtr buffer, unsigned total_size,
-    std::size_t content_size, wchar_t fill) {
-  std::size_t padding = total_size - content_size;
-  std::size_t left_padding = padding / 2;
-  Char fill_char = internal::CharTraits<Char>::cast(fill);
-  std::uninitialized_fill_n(buffer, left_padding, fill_char);
-  buffer += left_padding;
-  CharPtr content = buffer;
-  std::uninitialized_fill_n(buffer + content_size,
-                            padding - left_padding, fill_char);
-  return content;
-}
-
-template <typename Char>
-template <typename Spec>
-typename BasicWriter<Char>::CharPtr
-  BasicWriter<Char>::prepare_int_buffer(
-    unsigned num_digits, const Spec &spec,
-    const char *prefix, unsigned prefix_size) {
-  unsigned width = spec.width();
-  Alignment align = spec.align();
-  Char fill = internal::CharTraits<Char>::cast(spec.fill());
-  if (spec.precision() > static_cast<int>(num_digits)) {
-    // Octal prefix '0' is counted as a digit, so ignore it if precision
-    // is specified.
-    if (prefix_size > 0 && prefix[prefix_size - 1] == '0')
-      --prefix_size;
-    unsigned number_size =
-        prefix_size + internal::to_unsigned(spec.precision());
-    AlignSpec subspec(number_size, '0', ALIGN_NUMERIC);
-    if (number_size >= width)
-      return prepare_int_buffer(num_digits, subspec, prefix, prefix_size);
-    buffer_.reserve(width);
-    unsigned fill_size = width - number_size;
-    if (align != ALIGN_LEFT) {
-      CharPtr p = grow_buffer(fill_size);
-      std::uninitialized_fill(p, p + fill_size, fill);
-    }
-    CharPtr result = prepare_int_buffer(
-        num_digits, subspec, prefix, prefix_size);
-    if (align == ALIGN_LEFT) {
-      CharPtr p = grow_buffer(fill_size);
-      std::uninitialized_fill(p, p + fill_size, fill);
-    }
-    return result;
-  }
-  unsigned size = prefix_size + num_digits;
-  if (width <= size) {
-    CharPtr p = grow_buffer(size);
-    std::uninitialized_copy(prefix, prefix + prefix_size, p);
-    return p + size - 1;
-  }
-  CharPtr p = grow_buffer(width);
-  CharPtr end = p + width;
-  if (align == ALIGN_LEFT) {
-    std::uninitialized_copy(prefix, prefix + prefix_size, p);
-    p += size;
-    std::uninitialized_fill(p, end, fill);
-  } else if (align == ALIGN_CENTER) {
-    p = fill_padding(p, width, size, fill);
-    std::uninitialized_copy(prefix, prefix + prefix_size, p);
-    p += size;
-  } else {
-    if (align == ALIGN_NUMERIC) {
-      if (prefix_size != 0) {
-        p = std::uninitialized_copy(prefix, prefix + prefix_size, p);
-        size -= prefix_size;
-      }
-    } else {
-      std::uninitialized_copy(prefix, prefix + prefix_size, end - size);
-    }
-    std::uninitialized_fill(p, end - size, fill);
-    p = end;
-  }
-  return p - 1;
-}
-
-template <typename Char>
-template <typename T, typename Spec>
-void BasicWriter<Char>::write_int(T value, Spec spec) {
-  unsigned prefix_size = 0;
-  typedef typename internal::IntTraits<T>::MainType UnsignedType;
-  UnsignedType abs_value = static_cast<UnsignedType>(value);
-  char prefix[4] = "";
-  if (internal::is_negative(value)) {
-    prefix[0] = '-';
-    ++prefix_size;
-    abs_value = 0 - abs_value;
-  } else if (spec.flag(SIGN_FLAG)) {
-    prefix[0] = spec.flag(PLUS_FLAG) ? '+' : ' ';
-    ++prefix_size;
-  }
-  switch (spec.type()) {
-  case 0: case 'd': {
-    unsigned num_digits = internal::count_digits(abs_value);
-    CharPtr p = prepare_int_buffer(num_digits, spec, prefix, prefix_size) + 1;
-    internal::format_decimal(get(p), abs_value, 0);
-    break;
-  }
-  case 'x': case 'X': {
-    UnsignedType n = abs_value;
-    if (spec.flag(HASH_FLAG)) {
-      prefix[prefix_size++] = '0';
-      prefix[prefix_size++] = spec.type();
-    }
-    unsigned num_digits = 0;
-    do {
-      ++num_digits;
-    } while ((n >>= 4) != 0);
-    Char *p = get(prepare_int_buffer(
-      num_digits, spec, prefix, prefix_size));
-    n = abs_value;
-    const char *digits = spec.type() == 'x' ?
-        "0123456789abcdef" : "0123456789ABCDEF";
-    do {
-      *p-- = digits[n & 0xf];
-    } while ((n >>= 4) != 0);
-    break;
-  }
-  case 'b': case 'B': {
-    UnsignedType n = abs_value;
-    if (spec.flag(HASH_FLAG)) {
-      prefix[prefix_size++] = '0';
-      prefix[prefix_size++] = spec.type();
-    }
-    unsigned num_digits = 0;
-    do {
-      ++num_digits;
-    } while ((n >>= 1) != 0);
-    Char *p = get(prepare_int_buffer(num_digits, spec, prefix, prefix_size));
-    n = abs_value;
-    do {
-      *p-- = static_cast<Char>('0' + (n & 1));
-    } while ((n >>= 1) != 0);
-    break;
-  }
-  case 'o': {
-    UnsignedType n = abs_value;
-    if (spec.flag(HASH_FLAG))
-      prefix[prefix_size++] = '0';
-    unsigned num_digits = 0;
-    do {
-      ++num_digits;
-    } while ((n >>= 3) != 0);
-    Char *p = get(prepare_int_buffer(num_digits, spec, prefix, prefix_size));
-    n = abs_value;
-    do {
-      *p-- = static_cast<Char>('0' + (n & 7));
-    } while ((n >>= 3) != 0);
-    break;
-  }
-  case 'n': {
-    unsigned num_digits = internal::count_digits(abs_value);
-    fmt::StringRef sep = "";
-#ifndef ANDROID
-    sep = internal::thousands_sep(std::localeconv());
-#endif
-    unsigned size = static_cast<unsigned>(
-          num_digits + sep.size() * ((num_digits - 1) / 3));
-    CharPtr p = prepare_int_buffer(size, spec, prefix, prefix_size) + 1;
-    internal::format_decimal(get(p), abs_value, 0, internal::ThousandsSep(sep));
-    break;
-  }
-  default:
-    internal::report_unknown_type(
-      spec.type(), spec.flag(CHAR_FLAG) ? "char" : "integer");
-    break;
-  }
-}
-
-template <typename Char>
-template <typename T>
-void BasicWriter<Char>::write_double(T value, const FormatSpec &spec) {
-  // Check type.
-  char type = spec.type();
-  bool upper = false;
-  switch (type) {
-  case 0:
-    type = 'g';
-    break;
-  case 'e': case 'f': case 'g': case 'a':
-    break;
-  case 'F':
-#if FMT_MSC_VER
-    // MSVC's printf doesn't support 'F'.
-    type = 'f';
-#endif
-    // Fall through.
-  case 'E': case 'G': case 'A':
-    upper = true;
-    break;
-  default:
-    internal::report_unknown_type(type, "double");
-    break;
-  }
-
-  char sign = 0;
-  // Use isnegative instead of value < 0 because the latter is always
-  // false for NaN.
-  if (internal::FPUtil::isnegative(static_cast<double>(value))) {
-    sign = '-';
-    value = -value;
-  } else if (spec.flag(SIGN_FLAG)) {
-    sign = spec.flag(PLUS_FLAG) ? '+' : ' ';
-  }
-
-  if (internal::FPUtil::isnotanumber(value)) {
-    // Format NaN ourselves because sprintf's output is not consistent
-    // across platforms.
-    std::size_t nan_size = 4;
-    const char *nan = upper ? " NAN" : " nan";
-    if (!sign) {
-      --nan_size;
-      ++nan;
-    }
-    CharPtr out = write_str(nan, nan_size, spec);
-    if (sign)
-      *out = sign;
-    return;
-  }
-
-  if (internal::FPUtil::isinfinity(value)) {
-    // Format infinity ourselves because sprintf's output is not consistent
-    // across platforms.
-    std::size_t inf_size = 4;
-    const char *inf = upper ? " INF" : " inf";
-    if (!sign) {
-      --inf_size;
-      ++inf;
-    }
-    CharPtr out = write_str(inf, inf_size, spec);
-    if (sign)
-      *out = sign;
-    return;
-  }
-
-  std::size_t offset = buffer_.size();
-  unsigned width = spec.width();
-  if (sign) {
-    buffer_.reserve(buffer_.size() + (width > 1u ? width : 1u));
-    if (width > 0)
-      --width;
-    ++offset;
-  }
-
-  // Build format string.
-  enum { MAX_FORMAT_SIZE = 10}; // longest format: %#-*.*Lg
-  Char format[MAX_FORMAT_SIZE];
-  Char *format_ptr = format;
-  *format_ptr++ = '%';
-  unsigned width_for_sprintf = width;
-  if (spec.flag(HASH_FLAG))
-    *format_ptr++ = '#';
-  if (spec.align() == ALIGN_CENTER) {
-    width_for_sprintf = 0;
-  } else {
-    if (spec.align() == ALIGN_LEFT)
-      *format_ptr++ = '-';
-    if (width != 0)
-      *format_ptr++ = '*';
-  }
-  if (spec.precision() >= 0) {
-    *format_ptr++ = '.';
-    *format_ptr++ = '*';
-  }
-
-  append_float_length(format_ptr, value);
-  *format_ptr++ = type;
-  *format_ptr = '\0';
-
-  // Format using snprintf.
-  Char fill = internal::CharTraits<Char>::cast(spec.fill());
-  unsigned n = 0;
-  Char *start = 0;
-  for (;;) {
-    std::size_t buffer_size = buffer_.capacity() - offset;
-#if FMT_MSC_VER
-    // MSVC's vsnprintf_s doesn't work with zero size, so reserve
-    // space for at least one extra character to make the size non-zero.
-    // Note that the buffer's capacity will increase by more than 1.
-    if (buffer_size == 0) {
-      buffer_.reserve(offset + 1);
-      buffer_size = buffer_.capacity() - offset;
-    }
-#endif
-    start = &buffer_[offset];
-    int result = internal::CharTraits<Char>::format_float(
-        start, buffer_size, format, width_for_sprintf, spec.precision(), value);
-    if (result >= 0) {
-      n = internal::to_unsigned(result);
-      if (offset + n < buffer_.capacity())
-        break;  // The buffer is large enough - continue with formatting.
-      buffer_.reserve(offset + n + 1);
-    } else {
-      // If result is negative we ask to increase the capacity by at least 1,
-      // but as std::vector, the buffer grows exponentially.
-      buffer_.reserve(buffer_.capacity() + 1);
-    }
-  }
-  if (sign) {
-    if ((spec.align() != ALIGN_RIGHT && spec.align() != ALIGN_DEFAULT) ||
-        *start != ' ') {
-      *(start - 1) = sign;
-      sign = 0;
-    } else {
-      *(start - 1) = fill;
-    }
-    ++n;
-  }
-  if (spec.align() == ALIGN_CENTER && spec.width() > n) {
-    width = spec.width();
-    CharPtr p = grow_buffer(width);
-    std::memmove(get(p) + (width - n) / 2, get(p), n * sizeof(Char));
-    fill_padding(p, spec.width(), n, fill);
-    return;
-  }
-  if (spec.fill() != ' ' || sign) {
-    while (*start == ' ')
-      *start++ = fill;
-    if (sign)
-      *(start - 1) = sign;
-  }
-  grow_buffer(n);
-}
-
-/**
-  \rst
-  This class template provides operations for formatting and writing data
-  into a character stream. The output is stored in a memory buffer that grows
-  dynamically.
-
-  You can use one of the following typedefs for common character types
-  and the standard allocator:
-
-  +---------------+-----------------------------------------------------+
-  | Type          | Definition                                          |
-  +===============+=====================================================+
-  | MemoryWriter  | BasicMemoryWriter<char, std::allocator<char>>       |
-  +---------------+-----------------------------------------------------+
-  | WMemoryWriter | BasicMemoryWriter<wchar_t, std::allocator<wchar_t>> |
-  +---------------+-----------------------------------------------------+
-
-  **Example**::
-
-     MemoryWriter out;
-     out << "The answer is " << 42 << "\n";
-     out.write("({:+f}, {:+f})", -3.14, 3.14);
-
-  This will write the following output to the ``out`` object:
-
-  .. code-block:: none
-
-     The answer is 42
-     (-3.140000, +3.140000)
-
-  The output can be converted to an ``std::string`` with ``out.str()`` or
-  accessed as a C string with ``out.c_str()``.
-  \endrst
- */
-template <typename Char, typename Allocator = std::allocator<Char> >
-class BasicMemoryWriter : public BasicWriter<Char> {
- private:
-  internal::MemoryBuffer<Char, internal::INLINE_BUFFER_SIZE, Allocator> buffer_;
-
- public:
-  explicit BasicMemoryWriter(const Allocator& alloc = Allocator())
-    : BasicWriter<Char>(buffer_), buffer_(alloc) {}
-
-#if FMT_USE_RVALUE_REFERENCES
-  /**
-    \rst
-    Constructs a :class:`fmt::BasicMemoryWriter` object moving the content
-    of the other object to it.
-    \endrst
-   */
-  BasicMemoryWriter(BasicMemoryWriter &&other)
-    : BasicWriter<Char>(buffer_), buffer_(std::move(other.buffer_)) {
-  }
-
-  /**
-    \rst
-    Moves the content of the other ``BasicMemoryWriter`` object to this one.
-    \endrst
-   */
-  BasicMemoryWriter &operator=(BasicMemoryWriter &&other) {
-    buffer_ = std::move(other.buffer_);
-    return *this;
-  }
-#endif
-};
-
-typedef BasicMemoryWriter<char> MemoryWriter;
-typedef BasicMemoryWriter<wchar_t> WMemoryWriter;
-
-/**
-  \rst
-  This class template provides operations for formatting and writing data
-  into a fixed-size array. For writing into a dynamically growing buffer
-  use :class:`fmt::BasicMemoryWriter`.
-
-  Any write method will throw ``std::runtime_error`` if the output doesn't fit
-  into the array.
-
-  You can use one of the following typedefs for common character types:
-
-  +--------------+---------------------------+
-  | Type         | Definition                |
-  +==============+===========================+
-  | ArrayWriter  | BasicArrayWriter<char>    |
-  +--------------+---------------------------+
-  | WArrayWriter | BasicArrayWriter<wchar_t> |
-  +--------------+---------------------------+
-  \endrst
- */
-template <typename Char>
-class BasicArrayWriter : public BasicWriter<Char> {
- private:
-  internal::FixedBuffer<Char> buffer_;
-
- public:
-  /**
-   \rst
-   Constructs a :class:`fmt::BasicArrayWriter` object for *array* of the
-   given size.
-   \endrst
-   */
-  BasicArrayWriter(Char *array, std::size_t size)
-    : BasicWriter<Char>(buffer_), buffer_(array, size) {}
-
-  /**
-   \rst
-   Constructs a :class:`fmt::BasicArrayWriter` object for *array* of the
-   size known at compile time.
-   \endrst
-   */
-  template <std::size_t SIZE>
-  explicit BasicArrayWriter(Char (&array)[SIZE])
-    : BasicWriter<Char>(buffer_), buffer_(array, SIZE) {}
-};
-
-typedef BasicArrayWriter<char> ArrayWriter;
-typedef BasicArrayWriter<wchar_t> WArrayWriter;
-
-// Reports a system error without throwing an exception.
-// Can be used to report errors from destructors.
-FMT_API void report_system_error(int error_code,
-                                 StringRef message) FMT_NOEXCEPT;
-
-#if FMT_USE_WINDOWS_H
-
-/** A Windows error. */
-class WindowsError : public SystemError {
- private:
-  FMT_API void init(int error_code, CStringRef format_str, ArgList args);
-
- public:
-  /**
-   \rst
-   Constructs a :class:`fmt::WindowsError` object with the description
-   of the form
-
-   .. parsed-literal::
-     *<message>*: *<system-message>*
-
-   where *<message>* is the formatted message and *<system-message>* is the
-   system message corresponding to the error code.
-   *error_code* is a Windows error code as given by ``GetLastError``.
-   If *error_code* is not a valid error code such as -1, the system message
-   will look like "error -1".
-
-   **Example**::
-
-     // This throws a WindowsError with the description
-     //   cannot open file 'madeup': The system cannot find the file specified.
-     // or similar (system message may vary).
-     const char *filename = "madeup";
-     LPOFSTRUCT of = LPOFSTRUCT();
-     HFILE file = OpenFile(filename, &of, OF_READ);
-     if (file == HFILE_ERROR) {
-       throw fmt::WindowsError(GetLastError(),
-                               "cannot open file '{}'", filename);
-     }
-   \endrst
-  */
-  WindowsError(int error_code, CStringRef message) {
-    init(error_code, message, ArgList());
-  }
-  FMT_VARIADIC_CTOR(WindowsError, init, int, CStringRef)
-};
-
-// Reports a Windows error without throwing an exception.
-// Can be used to report errors from destructors.
-FMT_API void report_windows_error(int error_code,
-                                  StringRef message) FMT_NOEXCEPT;
-
-#endif
-
-enum Color { BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE };
-
-/**
-  Formats a string and prints it to stdout using ANSI escape sequences
-  to specify color (experimental).
-  Example:
-    print_colored(fmt::RED, "Elapsed time: {0:.2f} seconds", 1.23);
- */
-FMT_API void print_colored(Color c, CStringRef format, ArgList args);
-
-/**
-  \rst
-  Formats arguments and returns the result as a string.
-
-  **Example**::
-
-    std::string message = format("The answer is {}", 42);
-  \endrst
-*/
-inline std::string format(CStringRef format_str, ArgList args) {
-  MemoryWriter w;
-  w.write(format_str, args);
-  return w.str();
-}
-
-inline std::wstring format(WCStringRef format_str, ArgList args) {
-  WMemoryWriter w;
-  w.write(format_str, args);
-  return w.str();
-}
-
-/**
-  \rst
-  Prints formatted data to the file *f*.
-
-  **Example**::
-
-    print(stderr, "Don't {}!", "panic");
-  \endrst
- */
-FMT_API void print(std::FILE *f, CStringRef format_str, ArgList args);
-
-/**
-  \rst
-  Prints formatted data to ``stdout``.
-
-  **Example**::
-
-    print("Elapsed time: {0:.2f} seconds", 1.23);
-  \endrst
- */
-FMT_API void print(CStringRef format_str, ArgList args);
-
-template <typename Char>
-void printf(BasicWriter<Char> &w, BasicCStringRef<Char> format, ArgList args) {
-  internal::PrintfFormatter<Char>(args).format(w, format);
-}
-
-/**
-  \rst
-  Formats arguments and returns the result as a string.
-
-  **Example**::
-
-    std::string message = fmt::sprintf("The answer is %d", 42);
-  \endrst
-*/
-inline std::string sprintf(CStringRef format, ArgList args) {
-  MemoryWriter w;
-  printf(w, format, args);
-  return w.str();
-}
-
-inline std::wstring sprintf(WCStringRef format, ArgList args) {
-  WMemoryWriter w;
-  printf(w, format, args);
-  return w.str();
-}
-
-/**
-  \rst
-  Prints formatted data to the file *f*.
-
-  **Example**::
-
-    fmt::fprintf(stderr, "Don't %s!", "panic");
-  \endrst
- */
-FMT_API int fprintf(std::FILE *f, CStringRef format, ArgList args);
-
-/**
-  \rst
-  Prints formatted data to ``stdout``.
-
-  **Example**::
-
-    fmt::printf("Elapsed time: %.2f seconds", 1.23);
-  \endrst
- */
-inline int printf(CStringRef format, ArgList args) {
-  return fprintf(stdout, format, args);
-}
-
-/**
-  Fast integer formatter.
- */
-class FormatInt {
- private:
-  // Buffer should be large enough to hold all digits (digits10 + 1),
-  // a sign and a null character.
-  enum {BUFFER_SIZE = std::numeric_limits<ULongLong>::digits10 + 3};
-  mutable char buffer_[BUFFER_SIZE];
-  char *str_;
-
-  // Formats value in reverse and returns the number of digits.
-  char *format_decimal(ULongLong value) {
-    char *buffer_end = buffer_ + BUFFER_SIZE - 1;
-    while (value >= 100) {
-      // Integer division is slow so do it for a group of two digits instead
-      // of for every digit. The idea comes from the talk by Alexandrescu
-      // "Three Optimization Tips for C++". See speed-test for a comparison.
-      unsigned index = static_cast<unsigned>((value % 100) * 2);
-      value /= 100;
-      *--buffer_end = internal::Data::DIGITS[index + 1];
-      *--buffer_end = internal::Data::DIGITS[index];
-    }
-    if (value < 10) {
-      *--buffer_end = static_cast<char>('0' + value);
-      return buffer_end;
-    }
-    unsigned index = static_cast<unsigned>(value * 2);
-    *--buffer_end = internal::Data::DIGITS[index + 1];
-    *--buffer_end = internal::Data::DIGITS[index];
-    return buffer_end;
-  }
-
-  void FormatSigned(LongLong value) {
-    ULongLong abs_value = static_cast<ULongLong>(value);
-    bool negative = value < 0;
-    if (negative)
-      abs_value = 0 - abs_value;
-    str_ = format_decimal(abs_value);
-    if (negative)
-      *--str_ = '-';
-  }
-
- public:
-  explicit FormatInt(int value) { FormatSigned(value); }
-  explicit FormatInt(long value) { FormatSigned(value); }
-  explicit FormatInt(LongLong value) { FormatSigned(value); }
-  explicit FormatInt(unsigned value) : str_(format_decimal(value)) {}
-  explicit FormatInt(unsigned long value) : str_(format_decimal(value)) {}
-  explicit FormatInt(ULongLong value) : str_(format_decimal(value)) {}
-
-  /** Returns the number of characters written to the output buffer. */
-  std::size_t size() const {
-    return internal::to_unsigned(buffer_ - str_ + BUFFER_SIZE - 1);
-  }
-
-  /**
-    Returns a pointer to the output buffer content. No terminating null
-    character is appended.
-   */
-  const char *data() const { return str_; }
-
-  /**
-    Returns a pointer to the output buffer content with terminating null
-    character appended.
-   */
-  const char *c_str() const {
-    buffer_[BUFFER_SIZE - 1] = '\0';
-    return str_;
-  }
-
-  /**
-    \rst
-    Returns the content of the output buffer as an ``std::string``.
-    \endrst
-   */
-  std::string str() const { return std::string(str_, size()); }
-};
-
-// Formats a decimal integer value writing into buffer and returns
-// a pointer to the end of the formatted string. This function doesn't
-// write a terminating null character.
-template <typename T>
-inline void format_decimal(char *&buffer, T value) {
-  typedef typename internal::IntTraits<T>::MainType MainType;
-  MainType abs_value = static_cast<MainType>(value);
-  if (internal::is_negative(value)) {
-    *buffer++ = '-';
-    abs_value = 0 - abs_value;
-  }
-  if (abs_value < 100) {
-    if (abs_value < 10) {
-      *buffer++ = static_cast<char>('0' + abs_value);
-      return;
-    }
-    unsigned index = static_cast<unsigned>(abs_value * 2);
-    *buffer++ = internal::Data::DIGITS[index];
-    *buffer++ = internal::Data::DIGITS[index + 1];
-    return;
-  }
-  unsigned num_digits = internal::count_digits(abs_value);
-  internal::format_decimal(buffer, abs_value, num_digits);
-  buffer += num_digits;
-}
-
-/**
-  \rst
-  Returns a named argument for formatting functions.
-
-  **Example**::
-
-    print("Elapsed time: {s:.2f} seconds", arg("s", 1.23));
-
-  \endrst
- */
-template <typename T>
-inline internal::NamedArg<char> arg(StringRef name, const T &arg) {
-  return internal::NamedArg<char>(name, arg);
-}
-
-template <typename T>
-inline internal::NamedArg<wchar_t> arg(WStringRef name, const T &arg) {
-  return internal::NamedArg<wchar_t>(name, arg);
-}
-
-// The following two functions are deleted intentionally to disable
-// nested named arguments as in ``format("{}", arg("a", arg("b", 42)))``.
-template <typename Char>
-void arg(StringRef, const internal::NamedArg<Char>&) FMT_DELETED_OR_UNDEFINED;
-template <typename Char>
-void arg(WStringRef, const internal::NamedArg<Char>&) FMT_DELETED_OR_UNDEFINED;
-}
-
-#if FMT_GCC_VERSION
-// Use the system_header pragma to suppress warnings about variadic macros
-// because suppressing -Wvariadic-macros with the diagnostic pragma doesn't
-// work. It is used at the end because we want to suppress as little warnings
-// as possible.
-# pragma GCC system_header
-#endif
-
-// This is used to work around VC++ bugs in handling variadic macros.
-#define FMT_EXPAND(args) args
-
-// Returns the number of arguments.
-// Based on https://groups.google.com/forum/#!topic/comp.std.c/d-6Mj5Lko_s.
-#define FMT_NARG(...) FMT_NARG_(__VA_ARGS__, FMT_RSEQ_N())
-#define FMT_NARG_(...) FMT_EXPAND(FMT_ARG_N(__VA_ARGS__))
-#define FMT_ARG_N(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, N, ...) N
-#define FMT_RSEQ_N() 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0
-
-#define FMT_CONCAT(a, b) a##b
-#define FMT_FOR_EACH_(N, f, ...) \
-  FMT_EXPAND(FMT_CONCAT(FMT_FOR_EACH, N)(f, __VA_ARGS__))
-#define FMT_FOR_EACH(f, ...) \
-  FMT_EXPAND(FMT_FOR_EACH_(FMT_NARG(__VA_ARGS__), f, __VA_ARGS__))
-
-#define FMT_ADD_ARG_NAME(type, index) type arg##index
-#define FMT_GET_ARG_NAME(type, index) arg##index
-
-#if FMT_USE_VARIADIC_TEMPLATES
-# define FMT_VARIADIC_(Char, ReturnType, func, call, ...) \
-  template <typename... Args> \
-  ReturnType func(FMT_FOR_EACH(FMT_ADD_ARG_NAME, __VA_ARGS__), \
-      const Args & ... args) { \
-    typedef fmt::internal::ArgArray<sizeof...(Args)> ArgArray; \
-    typename ArgArray::Type array{ \
-      ArgArray::template make<fmt::BasicFormatter<Char> >(args)...}; \
-    call(FMT_FOR_EACH(FMT_GET_ARG_NAME, __VA_ARGS__), \
-      fmt::ArgList(fmt::internal::make_type(args...), array)); \
-  }
-#else
-// Defines a wrapper for a function taking __VA_ARGS__ arguments
-// and n additional arguments of arbitrary types.
-# define FMT_WRAP(Char, ReturnType, func, call, n, ...) \
-  template <FMT_GEN(n, FMT_MAKE_TEMPLATE_ARG)> \
-  inline ReturnType func(FMT_FOR_EACH(FMT_ADD_ARG_NAME, __VA_ARGS__), \
-      FMT_GEN(n, FMT_MAKE_ARG)) { \
-    fmt::internal::ArgArray<n>::Type arr; \
-    FMT_GEN(n, FMT_ASSIGN_##Char); \
-    call(FMT_FOR_EACH(FMT_GET_ARG_NAME, __VA_ARGS__), fmt::ArgList( \
-      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), arr)); \
-  }
-
-# define FMT_VARIADIC_(Char, ReturnType, func, call, ...) \
-  inline ReturnType func(FMT_FOR_EACH(FMT_ADD_ARG_NAME, __VA_ARGS__)) { \
-    call(FMT_FOR_EACH(FMT_GET_ARG_NAME, __VA_ARGS__), fmt::ArgList()); \
-  } \
-  FMT_WRAP(Char, ReturnType, func, call, 1, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 2, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 3, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 4, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 5, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 6, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 7, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 8, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 9, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 10, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 11, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 12, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 13, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 14, __VA_ARGS__) \
-  FMT_WRAP(Char, ReturnType, func, call, 15, __VA_ARGS__)
-#endif  // FMT_USE_VARIADIC_TEMPLATES
-
-/**
-  \rst
-  Defines a variadic function with the specified return type, function name
-  and argument types passed as variable arguments to this macro.
-
-  **Example**::
-
-    void print_error(const char *file, int line, const char *format,
-                     fmt::ArgList args) {
-      fmt::print("{}: {}: ", file, line);
-      fmt::print(format, args);
-    }
-    FMT_VARIADIC(void, print_error, const char *, int, const char *)
-
-  ``FMT_VARIADIC`` is used for compatibility with legacy C++ compilers that
-  don't implement variadic templates. You don't have to use this macro if
-  you don't need legacy compiler support and can use variadic templates
-  directly::
-
-    template <typename... Args>
-    void print_error(const char *file, int line, const char *format,
-                     const Args & ... args) {
-      fmt::print("{}: {}: ", file, line);
-      fmt::print(format, args...);
-    }
-  \endrst
- */
-#define FMT_VARIADIC(ReturnType, func, ...) \
-  FMT_VARIADIC_(char, ReturnType, func, return func, __VA_ARGS__)
-
-#define FMT_VARIADIC_W(ReturnType, func, ...) \
-  FMT_VARIADIC_(wchar_t, ReturnType, func, return func, __VA_ARGS__)
-
-#define FMT_CAPTURE_ARG_(id, index) ::fmt::arg(#id, id)
-
-#define FMT_CAPTURE_ARG_W_(id, index) ::fmt::arg(L###id, id)
-
-/**
-  \rst
-  Convenient macro to capture the arguments' names and values into several
-  ``fmt::arg(name, value)``.
-
-  **Example**::
-
-    int x = 1, y = 2;
-    print("point: ({x}, {y})", FMT_CAPTURE(x, y));
-    // same as:
-    // print("point: ({x}, {y})", arg("x", x), arg("y", y));
-
-  \endrst
- */
-#define FMT_CAPTURE(...) FMT_FOR_EACH(FMT_CAPTURE_ARG_, __VA_ARGS__)
-
-#define FMT_CAPTURE_W(...) FMT_FOR_EACH(FMT_CAPTURE_ARG_W_, __VA_ARGS__)
-
-namespace fmt {
-FMT_VARIADIC(std::string, format, CStringRef)
-FMT_VARIADIC_W(std::wstring, format, WCStringRef)
-FMT_VARIADIC(void, print, CStringRef)
-FMT_VARIADIC(void, print, std::FILE *, CStringRef)
-
-FMT_VARIADIC(void, print_colored, Color, CStringRef)
-FMT_VARIADIC(std::string, sprintf, CStringRef)
-FMT_VARIADIC_W(std::wstring, sprintf, WCStringRef)
-FMT_VARIADIC(int, printf, CStringRef)
-FMT_VARIADIC(int, fprintf, std::FILE *, CStringRef)
-
-namespace internal {
-template <typename Char>
-inline bool is_name_start(Char c) {
-  return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || '_' == c;
-}
-
-// Parses an unsigned integer advancing s to the end of the parsed input.
-// This function assumes that the first character of s is a digit.
-template <typename Char>
-unsigned parse_nonnegative_int(const Char *&s) {
-  assert('0' <= *s && *s <= '9');
-  unsigned value = 0;
-  do {
-    unsigned new_value = value * 10 + (*s++ - '0');
-    // Check if value wrapped around.
-    if (new_value < value) {
-      value = (std::numeric_limits<unsigned>::max)();
-      break;
-    }
-    value = new_value;
-  } while ('0' <= *s && *s <= '9');
-  // Convert to unsigned to prevent a warning.
-  unsigned max_int = (std::numeric_limits<int>::max)();
-  if (value > max_int)
-    FMT_THROW(FormatError("number is too big"));
-  return value;
-}
-
-inline void require_numeric_argument(const Arg &arg, char spec) {
-  if (arg.type > Arg::LAST_NUMERIC_TYPE) {
-    std::string message =
-        fmt::format("format specifier '{}' requires numeric argument", spec);
-    FMT_THROW(fmt::FormatError(message));
-  }
-}
-
-template <typename Char>
-void check_sign(const Char *&s, const Arg &arg) {
-  char sign = static_cast<char>(*s);
-  require_numeric_argument(arg, sign);
-  if (arg.type == Arg::UINT || arg.type == Arg::ULONG_LONG) {
-    FMT_THROW(FormatError(fmt::format(
-      "format specifier '{}' requires signed argument", sign)));
-  }
-  ++s;
-}
-}  // namespace internal
-
-template <typename Char, typename AF>
-inline internal::Arg BasicFormatter<Char, AF>::get_arg(
-    BasicStringRef<Char> arg_name, const char *&error) {
-  if (check_no_auto_index(error)) {
-    map_.init(args());
-    const internal::Arg *arg = map_.find(arg_name);
-    if (arg)
-      return *arg;
-    error = "argument not found";
-  }
-  return internal::Arg();
-}
-
-template <typename Char, typename AF>
-inline internal::Arg BasicFormatter<Char, AF>::parse_arg_index(const Char *&s) {
-  const char *error = 0;
-  internal::Arg arg = *s < '0' || *s > '9' ?
-        next_arg(error) : get_arg(internal::parse_nonnegative_int(s), error);
-  if (error) {
-    FMT_THROW(FormatError(
-                *s != '}' && *s != ':' ? "invalid format string" : error));
-  }
-  return arg;
-}
-
-template <typename Char, typename AF>
-inline internal::Arg BasicFormatter<Char, AF>::parse_arg_name(const Char *&s) {
-  assert(internal::is_name_start(*s));
-  const Char *start = s;
-  Char c;
-  do {
-    c = *++s;
-  } while (internal::is_name_start(c) || ('0' <= c && c <= '9'));
-  const char *error = 0;
-  internal::Arg arg = get_arg(BasicStringRef<Char>(start, s - start), error);
-  if (error)
-    FMT_THROW(FormatError(error));
-  return arg;
-}
-
-template <typename Char, typename ArgFormatter>
-const Char *BasicFormatter<Char, ArgFormatter>::format(
-    const Char *&format_str, const internal::Arg &arg) {
-  using internal::Arg;
-  const Char *s = format_str;
-  FormatSpec spec;
-  if (*s == ':') {
-    if (arg.type == Arg::CUSTOM) {
-      arg.custom.format(this, arg.custom.value, &s);
-      return s;
-    }
-    ++s;
-    // Parse fill and alignment.
-    if (Char c = *s) {
-      const Char *p = s + 1;
-      spec.align_ = ALIGN_DEFAULT;
-      do {
-        switch (*p) {
-          case '<':
-            spec.align_ = ALIGN_LEFT;
-            break;
-          case '>':
-            spec.align_ = ALIGN_RIGHT;
-            break;
-          case '=':
-            spec.align_ = ALIGN_NUMERIC;
-            break;
-          case '^':
-            spec.align_ = ALIGN_CENTER;
-            break;
-        }
-        if (spec.align_ != ALIGN_DEFAULT) {
-          if (p != s) {
-            if (c == '}') break;
-            if (c == '{')
-              FMT_THROW(FormatError("invalid fill character '{'"));
-            s += 2;
-            spec.fill_ = c;
-          } else ++s;
-          if (spec.align_ == ALIGN_NUMERIC)
-            require_numeric_argument(arg, '=');
-          break;
-        }
-      } while (--p >= s);
-    }
-
-    // Parse sign.
-    switch (*s) {
-      case '+':
-        check_sign(s, arg);
-        spec.flags_ |= SIGN_FLAG | PLUS_FLAG;
-        break;
-      case '-':
-        check_sign(s, arg);
-        spec.flags_ |= MINUS_FLAG;
-        break;
-      case ' ':
-        check_sign(s, arg);
-        spec.flags_ |= SIGN_FLAG;
-        break;
-    }
-
-    if (*s == '#') {
-      require_numeric_argument(arg, '#');
-      spec.flags_ |= HASH_FLAG;
-      ++s;
-    }
-
-    // Parse zero flag.
-    if (*s == '0') {
-      require_numeric_argument(arg, '0');
-      spec.align_ = ALIGN_NUMERIC;
-      spec.fill_ = '0';
-      ++s;
-    }
-
-    // Parse width.
-    if ('0' <= *s && *s <= '9') {
-      spec.width_ = internal::parse_nonnegative_int(s);
-    } else if (*s == '{') {
-      ++s;
-      Arg width_arg = internal::is_name_start(*s) ?
-            parse_arg_name(s) : parse_arg_index(s);
-      if (*s++ != '}')
-        FMT_THROW(FormatError("invalid format string"));
-      ULongLong value = 0;
-      switch (width_arg.type) {
-      case Arg::INT:
-        if (width_arg.int_value < 0)
-          FMT_THROW(FormatError("negative width"));
-        value = width_arg.int_value;
-        break;
-      case Arg::UINT:
-        value = width_arg.uint_value;
-        break;
-      case Arg::LONG_LONG:
-        if (width_arg.long_long_value < 0)
-          FMT_THROW(FormatError("negative width"));
-        value = width_arg.long_long_value;
-        break;
-      case Arg::ULONG_LONG:
-        value = width_arg.ulong_long_value;
-        break;
-      default:
-        FMT_THROW(FormatError("width is not integer"));
-      }
-      if (value > (std::numeric_limits<int>::max)())
-        FMT_THROW(FormatError("number is too big"));
-      spec.width_ = static_cast<int>(value);
-    }
-
-    // Parse precision.
-    if (*s == '.') {
-      ++s;
-      spec.precision_ = 0;
-      if ('0' <= *s && *s <= '9') {
-        spec.precision_ = internal::parse_nonnegative_int(s);
-      } else if (*s == '{') {
-        ++s;
-        Arg precision_arg = internal::is_name_start(*s) ?
-              parse_arg_name(s) : parse_arg_index(s);
-        if (*s++ != '}')
-          FMT_THROW(FormatError("invalid format string"));
-        ULongLong value = 0;
-        switch (precision_arg.type) {
-          case Arg::INT:
-            if (precision_arg.int_value < 0)
-              FMT_THROW(FormatError("negative precision"));
-            value = precision_arg.int_value;
-            break;
-          case Arg::UINT:
-            value = precision_arg.uint_value;
-            break;
-          case Arg::LONG_LONG:
-            if (precision_arg.long_long_value < 0)
-              FMT_THROW(FormatError("negative precision"));
-            value = precision_arg.long_long_value;
-            break;
-          case Arg::ULONG_LONG:
-            value = precision_arg.ulong_long_value;
-            break;
-          default:
-            FMT_THROW(FormatError("precision is not integer"));
-        }
-        if (value > (std::numeric_limits<int>::max)())
-          FMT_THROW(FormatError("number is too big"));
-        spec.precision_ = static_cast<int>(value);
-      } else {
-        FMT_THROW(FormatError("missing precision specifier"));
-      }
-      if (arg.type <= Arg::LAST_INTEGER_TYPE || arg.type == Arg::POINTER) {
-        FMT_THROW(FormatError(
-            fmt::format("precision not allowed in {} format specifier",
-            arg.type == Arg::POINTER ? "pointer" : "integer")));
-      }
-    }
-
-    // Parse type.
-    if (*s != '}' && *s)
-      spec.type_ = static_cast<char>(*s++);
-  }
-
-  if (*s++ != '}')
-    FMT_THROW(FormatError("missing '}' in format string"));
-
-  // Format argument.
-  ArgFormatter(*this, spec, s - 1).visit(arg);
-  return s;
-}
-
-template <typename Char, typename AF>
-void BasicFormatter<Char, AF>::format(BasicCStringRef<Char> format_str) {
-  const Char *s = format_str.c_str();
-  const Char *start = s;
-  while (*s) {
-    Char c = *s++;
-    if (c != '{' && c != '}') continue;
-    if (*s == c) {
-      write(writer_, start, s);
-      start = ++s;
-      continue;
-    }
-    if (c == '}')
-      FMT_THROW(FormatError("unmatched '}' in format string"));
-    write(writer_, start, s - 1);
-    internal::Arg arg = internal::is_name_start(*s) ?
-          parse_arg_name(s) : parse_arg_index(s);
-    start = s = format(s, arg);
-  }
-  write(writer_, start, s);
-}
-}  // namespace fmt
-
-#if FMT_USE_USER_DEFINED_LITERALS
-namespace fmt {
-namespace internal {
-
-template <typename Char>
-struct UdlFormat {
-  const Char *str;
-
-  template <typename... Args>
-  auto operator()(Args && ... args) const
-                  -> decltype(format(str, std::forward<Args>(args)...)) {
-    return format(str, std::forward<Args>(args)...);
-  }
-};
-
-template <typename Char>
-struct UdlArg {
-  const Char *str;
-
-  template <typename T>
-  NamedArg<Char> operator=(T &&value) const {
-    return {str, std::forward<T>(value)};
-  }
-};
-
-} // namespace internal
-
-inline namespace literals {
-
-/**
-  \rst
-  C++11 literal equivalent of :func:`fmt::format`.
-
-  **Example**::
-
-    using namespace fmt::literals;
-    std::string message = "The answer is {}"_format(42);
-  \endrst
- */
-inline internal::UdlFormat<char>
-operator"" _format(const char *s, std::size_t) { return {s}; }
-inline internal::UdlFormat<wchar_t>
-operator"" _format(const wchar_t *s, std::size_t) { return {s}; }
-
-/**
-  \rst
-  C++11 literal equivalent of :func:`fmt::arg`.
-
-  **Example**::
-
-    using namespace fmt::literals;
-    print("Elapsed time: {s:.2f} seconds", "s"_a=1.23);
-  \endrst
- */
-inline internal::UdlArg<char>
-operator"" _a(const char *s, std::size_t) { return {s}; }
-inline internal::UdlArg<wchar_t>
-operator"" _a(const wchar_t *s, std::size_t) { return {s}; }
-
-} // inline namespace literals
-} // namespace fmt
-#endif // FMT_USE_USER_DEFINED_LITERALS
-
-// Restore warnings.
-#if FMT_GCC_VERSION >= 406
-# pragma GCC diagnostic pop
-#endif
-
-#if defined(__clang__) && !defined(FMT_ICC_VERSION)
-# pragma clang diagnostic pop
-#endif
-
-#ifdef FMT_HEADER_ONLY
-# define FMT_FUNC inline
-# include "format.cc"
-#else
-# define FMT_FUNC
-#endif
-
-#endif  // FMT_FORMAT_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/core.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,1331 @@
+// Formatting library for C++ - the core API
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_CORE_H_
+#define FMT_CORE_H_
+
+#include <cassert>
+#include <cstdio>
+#include <cstring>
+#include <iterator>
+#include <string>
+#include <type_traits>
+
+// The fmt library version in the form major * 10000 + minor * 100 + patch.
+#define FMT_VERSION 50100
+
+#ifdef __has_feature
+# define FMT_HAS_FEATURE(x) __has_feature(x)
+#else
+# define FMT_HAS_FEATURE(x) 0
+#endif
+
+#ifdef __has_include
+# define FMT_HAS_INCLUDE(x) __has_include(x)
+#else
+# define FMT_HAS_INCLUDE(x) 0
+#endif
+
+#ifdef __has_cpp_attribute
+# define FMT_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
+#else
+# define FMT_HAS_CPP_ATTRIBUTE(x) 0
+#endif
+
+#if defined(__GNUC__) && !defined(__clang__)
+# define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+#else
+# define FMT_GCC_VERSION 0
+#endif
+
+#if __cplusplus >= 201103L || defined(__GXX_EXPERIMENTAL_CXX0X__)
+# define FMT_HAS_GXX_CXX11 FMT_GCC_VERSION
+#else
+# define FMT_HAS_GXX_CXX11 0
+#endif
+
+#ifdef _MSC_VER
+# define FMT_MSC_VER _MSC_VER
+#else
+# define FMT_MSC_VER 0
+#endif
+
+// Check if relaxed c++14 constexpr is supported.
+// GCC doesn't allow throw in constexpr until version 6 (bug 67371).
+#ifndef FMT_USE_CONSTEXPR
+# define FMT_USE_CONSTEXPR \
+  (FMT_HAS_FEATURE(cxx_relaxed_constexpr) || FMT_MSC_VER >= 1910 || \
+   (FMT_GCC_VERSION >= 600 && __cplusplus >= 201402L))
+#endif
+#if FMT_USE_CONSTEXPR
+# define FMT_CONSTEXPR constexpr
+# define FMT_CONSTEXPR_DECL constexpr
+#else
+# define FMT_CONSTEXPR inline
+# define FMT_CONSTEXPR_DECL
+#endif
+
+#ifndef FMT_OVERRIDE
+# if FMT_HAS_FEATURE(cxx_override) || \
+     (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || \
+     FMT_MSC_VER >= 1900
+#  define FMT_OVERRIDE override
+# else
+#  define FMT_OVERRIDE
+# endif
+#endif
+
+#if FMT_HAS_FEATURE(cxx_explicit_conversions) || \
+    FMT_MSC_VER >= 1800
+# define FMT_EXPLICIT explicit
+#else
+# define FMT_EXPLICIT
+#endif
+
+#ifndef FMT_NULL
+# if FMT_HAS_FEATURE(cxx_nullptr) || \
+   (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || \
+   FMT_MSC_VER >= 1600
+#  define FMT_NULL nullptr
+#  define FMT_USE_NULLPTR 1
+# else
+#  define FMT_NULL NULL
+# endif
+#endif
+
+#ifndef FMT_USE_NULLPTR
+# define FMT_USE_NULLPTR 0
+#endif
+
+#if FMT_HAS_CPP_ATTRIBUTE(noreturn)
+# define FMT_NORETURN [[noreturn]]
+#else
+# define FMT_NORETURN
+#endif
+
+// Check if exceptions are disabled.
+#if defined(__GNUC__) && !defined(__EXCEPTIONS)
+# define FMT_EXCEPTIONS 0
+#elif FMT_MSC_VER && !_HAS_EXCEPTIONS
+# define FMT_EXCEPTIONS 0
+#endif
+#ifndef FMT_EXCEPTIONS
+# define FMT_EXCEPTIONS 1
+#endif
+
+// Define FMT_USE_NOEXCEPT to make fmt use noexcept (C++11 feature).
+#ifndef FMT_USE_NOEXCEPT
+# define FMT_USE_NOEXCEPT 0
+#endif
+
+#if FMT_USE_NOEXCEPT || FMT_HAS_FEATURE(cxx_noexcept) || \
+    (FMT_GCC_VERSION >= 408 && FMT_HAS_GXX_CXX11) || \
+    FMT_MSC_VER >= 1900
+# define FMT_DETECTED_NOEXCEPT noexcept
+#else
+# define FMT_DETECTED_NOEXCEPT throw()
+#endif
+
+#ifndef FMT_NOEXCEPT
+# if FMT_EXCEPTIONS
+#  define FMT_NOEXCEPT FMT_DETECTED_NOEXCEPT
+# else
+#  define FMT_NOEXCEPT
+# endif
+#endif
+
+// This is needed because GCC still uses throw() in its headers when exceptions
+// are disabled.
+#if FMT_GCC_VERSION
+# define FMT_DTOR_NOEXCEPT FMT_DETECTED_NOEXCEPT
+#else
+# define FMT_DTOR_NOEXCEPT FMT_NOEXCEPT
+#endif
+
+#ifndef FMT_BEGIN_NAMESPACE
+# if FMT_HAS_FEATURE(cxx_inline_namespaces) || FMT_GCC_VERSION >= 404 || \
+     FMT_MSC_VER >= 1900
+#  define FMT_INLINE_NAMESPACE inline namespace
+#  define FMT_END_NAMESPACE }}
+# else
+#  define FMT_INLINE_NAMESPACE namespace
+#  define FMT_END_NAMESPACE } using namespace v5; }
+# endif
+# define FMT_BEGIN_NAMESPACE namespace fmt { FMT_INLINE_NAMESPACE v5 {
+#endif
+
+#if !defined(FMT_HEADER_ONLY) && defined(_WIN32)
+# ifdef FMT_EXPORT
+#  define FMT_API __declspec(dllexport)
+# elif defined(FMT_SHARED)
+#  define FMT_API __declspec(dllimport)
+# endif
+#endif
+#ifndef FMT_API
+# define FMT_API
+#endif
+
+#ifndef FMT_ASSERT
+# define FMT_ASSERT(condition, message) assert((condition) && message)
+#endif
+
+#define FMT_DELETED = delete
+
+// A macro to disallow the copy construction and assignment.
+#define FMT_DISALLOW_COPY_AND_ASSIGN(Type) \
+    Type(const Type &) FMT_DELETED; \
+    void operator=(const Type &) FMT_DELETED
+
+// libc++ supports string_view in pre-c++17.
+#if (FMT_HAS_INCLUDE(<string_view>) && \
+      (__cplusplus > 201402L || defined(_LIBCPP_VERSION))) || \
+    (defined(_MSVC_LANG) && _MSVC_LANG > 201402L && _MSC_VER >= 1910)
+# include <string_view>
+# define FMT_USE_STD_STRING_VIEW
+#elif (FMT_HAS_INCLUDE(<experimental/string_view>) && \
+       __cplusplus >= 201402L)
+# include <experimental/string_view>
+# define FMT_USE_EXPERIMENTAL_STRING_VIEW
+#endif
+
+// std::result_of is defined in <functional> in gcc 4.4.
+#if FMT_GCC_VERSION && FMT_GCC_VERSION <= 404
+# include <functional>
+#endif
+
+FMT_BEGIN_NAMESPACE
+
+namespace internal {
+
+// An implementation of declval for pre-C++11 compilers such as gcc 4.
+template <typename T>
+typename std::add_rvalue_reference<T>::type declval() FMT_NOEXCEPT;
+
+// Casts nonnegative integer to unsigned.
+template <typename Int>
+FMT_CONSTEXPR typename std::make_unsigned<Int>::type to_unsigned(Int value) {
+  FMT_ASSERT(value >= 0, "negative value");
+  return static_cast<typename std::make_unsigned<Int>::type>(value);
+}
+
+}
+
+/**
+  An implementation of ``std::basic_string_view`` for pre-C++17. It provides a
+  subset of the API. ``fmt::basic_string_view`` is used for format strings even
+  if ``std::string_view`` is available to prevent issues when a library is
+  compiled with a different ``-std`` option than the client code (which is not
+  recommended).
+ */
+template <typename Char>
+class basic_string_view {
+ private:
+  const Char *data_;
+  size_t size_;
+
+ public:
+  typedef Char char_type;
+  typedef const Char *iterator;
+
+  // Standard basic_string_view type.
+#if defined(FMT_USE_STD_STRING_VIEW)
+  typedef std::basic_string_view<Char> type;
+#elif defined(FMT_USE_EXPERIMENTAL_STRING_VIEW)
+  typedef std::experimental::basic_string_view<Char> type;
+#else
+  struct type {
+    const char *data() const { return FMT_NULL; }
+    size_t size() const { return 0; }
+  };
+#endif
+
+  FMT_CONSTEXPR basic_string_view() FMT_NOEXCEPT : data_(FMT_NULL), size_(0) {}
+
+  /** Constructs a string reference object from a C string and a size. */
+  FMT_CONSTEXPR basic_string_view(const Char *s, size_t count) FMT_NOEXCEPT
+    : data_(s), size_(count) {}
+
+  /**
+    \rst
+    Constructs a string reference object from a C string computing
+    the size with ``std::char_traits<Char>::length``.
+    \endrst
+   */
+  basic_string_view(const Char *s)
+    : data_(s), size_(std::char_traits<Char>::length(s)) {}
+
+  /** Constructs a string reference from a ``std::basic_string`` object. */
+  template <typename Alloc>
+  FMT_CONSTEXPR basic_string_view(
+      const std::basic_string<Char, Alloc> &s) FMT_NOEXCEPT
+  : data_(s.c_str()), size_(s.size()) {}
+
+  FMT_CONSTEXPR basic_string_view(type s) FMT_NOEXCEPT
+  : data_(s.data()), size_(s.size()) {}
+
+  /** Returns a pointer to the string data. */
+  const Char *data() const { return data_; }
+
+  /** Returns the string size. */
+  FMT_CONSTEXPR size_t size() const { return size_; }
+
+  FMT_CONSTEXPR iterator begin() const { return data_; }
+  FMT_CONSTEXPR iterator end() const { return data_ + size_; }
+
+  FMT_CONSTEXPR void remove_prefix(size_t n) {
+    data_ += n;
+    size_ -= n;
+  }
+
+  // Lexicographically compare this string reference to other.
+  int compare(basic_string_view other) const {
+    size_t str_size = size_ < other.size_ ? size_ : other.size_;
+    int result = std::char_traits<Char>::compare(data_, other.data_, str_size);
+    if (result == 0)
+      result = size_ == other.size_ ? 0 : (size_ < other.size_ ? -1 : 1);
+    return result;
+  }
+
+  friend bool operator==(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) == 0;
+  }
+  friend bool operator!=(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) != 0;
+  }
+  friend bool operator<(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) < 0;
+  }
+  friend bool operator<=(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) <= 0;
+  }
+  friend bool operator>(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) > 0;
+  }
+  friend bool operator>=(basic_string_view lhs, basic_string_view rhs) {
+    return lhs.compare(rhs) >= 0;
+  }
+};
+
+typedef basic_string_view<char> string_view;
+typedef basic_string_view<wchar_t> wstring_view;
+
+template <typename Context>
+class basic_format_arg;
+
+template <typename Context>
+class basic_format_args;
+
+// A formatter for objects of type T.
+template <typename T, typename Char = char, typename Enable = void>
+struct formatter;
+
+namespace internal {
+
+/** A contiguous memory buffer with an optional growing ability. */
+template <typename T>
+class basic_buffer {
+ private:
+  FMT_DISALLOW_COPY_AND_ASSIGN(basic_buffer);
+
+  T *ptr_;
+  std::size_t size_;
+  std::size_t capacity_;
+
+ protected:
+  basic_buffer(T *p = FMT_NULL, std::size_t sz = 0, std::size_t cap = 0)
+    FMT_NOEXCEPT: ptr_(p), size_(sz), capacity_(cap) {}
+
+  /** Sets the buffer data and capacity. */
+  void set(T *buf_data, std::size_t buf_capacity) FMT_NOEXCEPT {
+    ptr_ = buf_data;
+    capacity_ = buf_capacity;
+  }
+
+  /** Increases the buffer capacity to hold at least *capacity* elements. */
+  virtual void grow(std::size_t capacity) = 0;
+
+ public:
+  typedef T value_type;
+  typedef const T &const_reference;
+
+  virtual ~basic_buffer() {}
+
+  T *begin() FMT_NOEXCEPT { return ptr_; }
+  T *end() FMT_NOEXCEPT { return ptr_ + size_; }
+
+  /** Returns the size of this buffer. */
+  std::size_t size() const FMT_NOEXCEPT { return size_; }
+
+  /** Returns the capacity of this buffer. */
+  std::size_t capacity() const FMT_NOEXCEPT { return capacity_; }
+
+  /** Returns a pointer to the buffer data. */
+  T *data() FMT_NOEXCEPT { return ptr_; }
+
+  /** Returns a pointer to the buffer data. */
+  const T *data() const FMT_NOEXCEPT { return ptr_; }
+
+  /**
+    Resizes the buffer. If T is a POD type new elements may not be initialized.
+   */
+  void resize(std::size_t new_size) {
+    reserve(new_size);
+    size_ = new_size;
+  }
+
+  /** Reserves space to store at least *capacity* elements. */
+  void reserve(std::size_t new_capacity) {
+    if (new_capacity > capacity_)
+      grow(new_capacity);
+  }
+
+  void push_back(const T &value) {
+    reserve(size_ + 1);
+    ptr_[size_++] = value;
+  }
+
+  /** Appends data to the end of the buffer. */
+  template <typename U>
+  void append(const U *begin, const U *end);
+
+  T &operator[](std::size_t index) { return ptr_[index]; }
+  const T &operator[](std::size_t index) const { return ptr_[index]; }
+};
+
+typedef basic_buffer<char> buffer;
+typedef basic_buffer<wchar_t> wbuffer;
+
+// A container-backed buffer.
+template <typename Container>
+class container_buffer : public basic_buffer<typename Container::value_type> {
+ private:
+  Container &container_;
+
+ protected:
+  void grow(std::size_t capacity) FMT_OVERRIDE {
+    container_.resize(capacity);
+    this->set(&container_[0], capacity);
+  }
+
+ public:
+  explicit container_buffer(Container &c)
+    : basic_buffer<typename Container::value_type>(&c[0], c.size(), c.size()),
+      container_(c) {}
+};
+
+struct error_handler {
+  FMT_CONSTEXPR error_handler() {}
+  FMT_CONSTEXPR error_handler(const error_handler &) {}
+
+  // This function is intentionally not constexpr to give a compile-time error.
+  FMT_API void on_error(const char *message);
+};
+
+// Formatting of wide characters and strings into a narrow output is disallowed:
+//   fmt::format("{}", L"test"); // error
+// To fix this, use a wide format string:
+//   fmt::format(L"{}", L"test");
+template <typename Char>
+inline void require_wchar() {
+  static_assert(
+      std::is_same<wchar_t, Char>::value,
+      "formatting of wide characters into a narrow output is disallowed");
+}
+
+template <typename Char>
+struct named_arg_base;
+
+template <typename T, typename Char>
+struct named_arg;
+
+template <typename T>
+struct is_named_arg : std::false_type {};
+
+template <typename T, typename Char>
+struct is_named_arg<named_arg<T, Char>> : std::true_type {};
+
+enum type {
+  none_type, named_arg_type,
+  // Integer types should go first,
+  int_type, uint_type, long_long_type, ulong_long_type, bool_type, char_type,
+  last_integer_type = char_type,
+  // followed by floating-point types.
+  double_type, long_double_type, last_numeric_type = long_double_type,
+  cstring_type, string_type, pointer_type, custom_type
+};
+
+FMT_CONSTEXPR bool is_integral(type t) {
+  FMT_ASSERT(t != internal::named_arg_type, "invalid argument type");
+  return t > internal::none_type && t <= internal::last_integer_type;
+}
+
+FMT_CONSTEXPR bool is_arithmetic(type t) {
+  FMT_ASSERT(t != internal::named_arg_type, "invalid argument type");
+  return t > internal::none_type && t <= internal::last_numeric_type;
+}
+
+template <typename T, typename Char, bool ENABLE = true>
+struct convert_to_int {
+  enum {
+    value = !std::is_arithmetic<T>::value && std::is_convertible<T, int>::value
+  };
+};
+
+template <typename Char>
+struct string_value {
+  const Char *value;
+  std::size_t size;
+};
+
+template <typename Context>
+struct custom_value {
+  const void *value;
+  void (*format)(const void *arg, Context &ctx);
+};
+
+// A formatting argument value.
+template <typename Context>
+class value {
+ public:
+  typedef typename Context::char_type char_type;
+
+  union {
+    int int_value;
+    unsigned uint_value;
+    long long long_long_value;
+    unsigned long long ulong_long_value;
+    double double_value;
+    long double long_double_value;
+    const void *pointer;
+    string_value<char_type> string;
+    string_value<signed char> sstring;
+    string_value<unsigned char> ustring;
+    custom_value<Context> custom;
+  };
+
+  FMT_CONSTEXPR value(int val = 0) : int_value(val) {}
+  value(unsigned val) { uint_value = val; }
+  value(long long val) { long_long_value = val; }
+  value(unsigned long long val) { ulong_long_value = val; }
+  value(double val) { double_value = val; }
+  value(long double val) { long_double_value = val; }
+  value(const char_type *val) { string.value = val; }
+  value(const signed char *val) {
+    static_assert(std::is_same<char, char_type>::value,
+                  "incompatible string types");
+    sstring.value = val;
+  }
+  value(const unsigned char *val) {
+    static_assert(std::is_same<char, char_type>::value,
+                  "incompatible string types");
+    ustring.value = val;
+  }
+  value(basic_string_view<char_type> val) {
+    string.value = val.data();
+    string.size = val.size();
+  }
+  value(const void *val) { pointer = val; }
+
+  template <typename T>
+  explicit value(const T &val) {
+    custom.value = &val;
+    custom.format = &format_custom_arg<T>;
+  }
+
+  const named_arg_base<char_type> &as_named_arg() {
+    return *static_cast<const named_arg_base<char_type>*>(pointer);
+  }
+
+ private:
+  // Formats an argument of a custom type, such as a user-defined class.
+  template <typename T>
+  static void format_custom_arg(const void *arg, Context &ctx) {
+    // Get the formatter type through the context to allow different contexts
+    // have different extension points, e.g. `formatter<T>` for `format` and
+    // `printf_formatter<T>` for `printf`.
+    typename Context::template formatter_type<T>::type f;
+    auto &&parse_ctx = ctx.parse_context();
+    parse_ctx.advance_to(f.parse(parse_ctx));
+    ctx.advance_to(f.format(*static_cast<const T*>(arg), ctx));
+  }
+};
+
+template <typename Context, type TYPE>
+struct typed_value : value<Context> {
+  static const type type_tag = TYPE;
+
+  template <typename T>
+  FMT_CONSTEXPR typed_value(const T &val) : value<Context>(val) {}
+};
+
+template <typename Context, typename T>
+FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T &value);
+
+#define FMT_MAKE_VALUE(TAG, ArgType, ValueType) \
+  template <typename C> \
+  FMT_CONSTEXPR typed_value<C, TAG> make_value(ArgType val) { \
+    return static_cast<ValueType>(val); \
+  }
+
+#define FMT_MAKE_VALUE_SAME(TAG, Type) \
+  template <typename C> \
+  FMT_CONSTEXPR typed_value<C, TAG> make_value(Type val) { \
+    return val; \
+  }
+
+FMT_MAKE_VALUE(bool_type, bool, int)
+FMT_MAKE_VALUE(int_type, short, int)
+FMT_MAKE_VALUE(uint_type, unsigned short, unsigned)
+FMT_MAKE_VALUE_SAME(int_type, int)
+FMT_MAKE_VALUE_SAME(uint_type, unsigned)
+
+// To minimize the number of types we need to deal with, long is translated
+// either to int or to long long depending on its size.
+typedef std::conditional<sizeof(long) == sizeof(int), int, long long>::type
+        long_type;
+FMT_MAKE_VALUE(
+    (sizeof(long) == sizeof(int) ? int_type : long_long_type), long, long_type)
+typedef std::conditional<sizeof(unsigned long) == sizeof(unsigned),
+                         unsigned, unsigned long long>::type ulong_type;
+FMT_MAKE_VALUE(
+    (sizeof(unsigned long) == sizeof(unsigned) ? uint_type : ulong_long_type),
+    unsigned long, ulong_type)
+
+FMT_MAKE_VALUE_SAME(long_long_type, long long)
+FMT_MAKE_VALUE_SAME(ulong_long_type, unsigned long long)
+FMT_MAKE_VALUE(int_type, signed char, int)
+FMT_MAKE_VALUE(uint_type, unsigned char, unsigned)
+FMT_MAKE_VALUE(char_type, char, int)
+
+#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
+template <typename C>
+inline typed_value<C, char_type> make_value(wchar_t val) {
+  require_wchar<typename C::char_type>();
+  return static_cast<int>(val);
+}
+#endif
+
+FMT_MAKE_VALUE(double_type, float, double)
+FMT_MAKE_VALUE_SAME(double_type, double)
+FMT_MAKE_VALUE_SAME(long_double_type, long double)
+
+// Formatting of wide strings into a narrow buffer and multibyte strings
+// into a wide buffer is disallowed (https://github.com/fmtlib/fmt/pull/606).
+FMT_MAKE_VALUE(cstring_type, typename C::char_type*,
+               const typename C::char_type*)
+FMT_MAKE_VALUE(cstring_type, const typename C::char_type*,
+               const typename C::char_type*)
+
+FMT_MAKE_VALUE(cstring_type, signed char*, const signed char*)
+FMT_MAKE_VALUE_SAME(cstring_type, const signed char*)
+FMT_MAKE_VALUE(cstring_type, unsigned char*, const unsigned char*)
+FMT_MAKE_VALUE_SAME(cstring_type, const unsigned char*)
+FMT_MAKE_VALUE_SAME(string_type, basic_string_view<typename C::char_type>)
+FMT_MAKE_VALUE(string_type,
+               typename basic_string_view<typename C::char_type>::type,
+               basic_string_view<typename C::char_type>)
+FMT_MAKE_VALUE(string_type, const std::basic_string<typename C::char_type>&,
+               basic_string_view<typename C::char_type>)
+FMT_MAKE_VALUE(pointer_type, void*, const void*)
+FMT_MAKE_VALUE_SAME(pointer_type, const void*)
+
+#if FMT_USE_NULLPTR
+FMT_MAKE_VALUE(pointer_type, std::nullptr_t, const void*)
+#endif
+
+// Formatting of arbitrary pointers is disallowed. If you want to output a
+// pointer cast it to "void *" or "const void *". In particular, this forbids
+// formatting of "[const] volatile char *" which is printed as bool by
+// iostreams.
+template <typename C, typename T>
+typename std::enable_if<!std::is_same<T, typename C::char_type>::value>::type
+    make_value(const T *) {
+  static_assert(!sizeof(T), "formatting of non-void pointers is disallowed");
+}
+
+template <typename C, typename T>
+inline typename std::enable_if<
+    std::is_enum<T>::value && convert_to_int<T, typename C::char_type>::value,
+    typed_value<C, int_type>>::type
+  make_value(const T &val) { return static_cast<int>(val); }
+
+template <typename C, typename T, typename Char = typename C::char_type>
+inline typename std::enable_if<
+    !convert_to_int<T, Char>::value &&
+    !std::is_convertible<T, basic_string_view<Char>>::value,
+    // Implicit conversion to std::string is not handled here because it's
+    // unsafe: https://github.com/fmtlib/fmt/issues/729
+    typed_value<C, custom_type>>::type
+  make_value(const T &val) { return val; }
+
+template <typename C, typename T>
+typed_value<C, named_arg_type>
+    make_value(const named_arg<T, typename C::char_type> &val) {
+  basic_format_arg<C> arg = make_arg<C>(val.value);
+  std::memcpy(val.data, &arg, sizeof(arg));
+  return static_cast<const void*>(&val);
+}
+
+// Maximum number of arguments with packed types.
+enum { max_packed_args = 15 };
+
+template <typename Context>
+class arg_map;
+
+template <typename>
+struct result_of;
+
+template <typename F, typename... Args>
+struct result_of<F(Args...)> {
+  // A workaround for gcc 4.4 that doesn't allow F to be a reference.
+  typedef typename std::result_of<
+    typename std::remove_reference<F>::type(Args...)>::type type;
+};
+}
+
+// A formatting argument. It is a trivially copyable/constructible type to
+// allow storage in basic_memory_buffer.
+template <typename Context>
+class basic_format_arg {
+ private:
+  internal::value<Context> value_;
+  internal::type type_;
+
+  template <typename ContextType, typename T>
+  friend FMT_CONSTEXPR basic_format_arg<ContextType>
+    internal::make_arg(const T &value);
+
+  template <typename Visitor, typename Ctx>
+  friend FMT_CONSTEXPR typename internal::result_of<Visitor(int)>::type
+    visit(Visitor &&vis, basic_format_arg<Ctx> arg);
+
+  friend class basic_format_args<Context>;
+  friend class internal::arg_map<Context>;
+
+  typedef typename Context::char_type char_type;
+
+ public:
+  class handle {
+   public:
+    explicit handle(internal::custom_value<Context> custom): custom_(custom) {}
+
+    void format(Context &ctx) const { custom_.format(custom_.value, ctx); }
+
+   private:
+    internal::custom_value<Context> custom_;
+  };
+
+  FMT_CONSTEXPR basic_format_arg() : type_(internal::none_type) {}
+
+  FMT_EXPLICIT operator bool() const FMT_NOEXCEPT {
+    return type_ != internal::none_type;
+  }
+
+  internal::type type() const { return type_; }
+
+  bool is_integral() const { return internal::is_integral(type_); }
+  bool is_arithmetic() const { return internal::is_arithmetic(type_); }
+};
+
+// Parsing context consisting of a format string range being parsed and an
+// argument counter for automatic indexing.
+template <typename Char, typename ErrorHandler = internal::error_handler>
+class basic_parse_context : private ErrorHandler {
+ private:
+  basic_string_view<Char> format_str_;
+  int next_arg_id_;
+
+ public:
+  typedef Char char_type;
+  typedef typename basic_string_view<Char>::iterator iterator;
+
+  explicit FMT_CONSTEXPR basic_parse_context(
+      basic_string_view<Char> format_str, ErrorHandler eh = ErrorHandler())
+    : ErrorHandler(eh), format_str_(format_str), next_arg_id_(0) {}
+
+  // Returns an iterator to the beginning of the format string range being
+  // parsed.
+  FMT_CONSTEXPR iterator begin() const FMT_NOEXCEPT {
+    return format_str_.begin();
+  }
+
+  // Returns an iterator past the end of the format string range being parsed.
+  FMT_CONSTEXPR iterator end() const FMT_NOEXCEPT { return format_str_.end(); }
+
+  // Advances the begin iterator to ``it``.
+  FMT_CONSTEXPR void advance_to(iterator it) {
+    format_str_.remove_prefix(internal::to_unsigned(it - begin()));
+  }
+
+  // Returns the next argument index.
+  FMT_CONSTEXPR unsigned next_arg_id();
+
+  FMT_CONSTEXPR bool check_arg_id(unsigned) {
+    if (next_arg_id_ > 0) {
+      on_error("cannot switch from automatic to manual argument indexing");
+      return false;
+    }
+    next_arg_id_ = -1;
+    return true;
+  }
+  void check_arg_id(basic_string_view<Char>) {}
+
+  FMT_CONSTEXPR void on_error(const char *message) {
+    ErrorHandler::on_error(message);
+  }
+
+  FMT_CONSTEXPR ErrorHandler error_handler() const { return *this; }
+};
+
+typedef basic_parse_context<char> parse_context;
+typedef basic_parse_context<wchar_t> wparse_context;
+
+namespace internal {
+// A map from argument names to their values for named arguments.
+template <typename Context>
+class arg_map {
+ private:
+  FMT_DISALLOW_COPY_AND_ASSIGN(arg_map);
+
+  typedef typename Context::char_type char_type;
+
+  struct entry {
+    basic_string_view<char_type> name;
+    basic_format_arg<Context> arg;
+  };
+
+  entry *map_;
+  unsigned size_;
+
+  void push_back(value<Context> val) {
+    const internal::named_arg_base<char_type> &named = val.as_named_arg();
+    map_[size_] = entry{named.name, named.template deserialize<Context>()};
+    ++size_;
+  }
+
+ public:
+  arg_map() : map_(FMT_NULL), size_(0) {}
+  void init(const basic_format_args<Context> &args);
+  ~arg_map() { delete [] map_; }
+
+  basic_format_arg<Context> find(basic_string_view<char_type> name) const {
+    // The list is unsorted, so just return the first matching name.
+    for (entry *it = map_, *end = map_ + size_; it != end; ++it) {
+      if (it->name == name)
+        return it->arg;
+    }
+    return basic_format_arg<Context>();
+  }
+};
+
+template <typename OutputIt, typename Context, typename Char>
+class context_base {
+ public:
+  typedef OutputIt iterator;
+
+ private:
+  basic_parse_context<Char> parse_context_;
+  iterator out_;
+  basic_format_args<Context> args_;
+
+ protected:
+  typedef Char char_type;
+  typedef basic_format_arg<Context> format_arg;
+
+  context_base(OutputIt out, basic_string_view<char_type> format_str,
+               basic_format_args<Context> ctx_args)
+  : parse_context_(format_str), out_(out), args_(ctx_args) {}
+
+  // Returns the argument with specified index.
+  format_arg do_get_arg(unsigned arg_id) {
+    format_arg arg = args_.get(arg_id);
+    if (!arg)
+      parse_context_.on_error("argument index out of range");
+    return arg;
+  }
+
+  // Checks if manual indexing is used and returns the argument with
+  // specified index.
+  format_arg get_arg(unsigned arg_id) {
+    return this->parse_context().check_arg_id(arg_id) ?
+      this->do_get_arg(arg_id) : format_arg();
+  }
+
+ public:
+  basic_parse_context<char_type> &parse_context() {
+    return parse_context_;
+  }
+
+  internal::error_handler error_handler() {
+    return parse_context_.error_handler();
+  }
+
+  void on_error(const char *message) { parse_context_.on_error(message); }
+
+  // Returns an iterator to the beginning of the output range.
+  iterator out() { return out_; }
+  iterator begin() { return out_; }  // deprecated
+
+  // Advances the begin iterator to ``it``.
+  void advance_to(iterator it) { out_ = it; }
+
+  basic_format_args<Context> args() const { return args_; }
+};
+
+// Extracts a reference to the container from back_insert_iterator.
+template <typename Container>
+inline Container &get_container(std::back_insert_iterator<Container> it) {
+  typedef std::back_insert_iterator<Container> bi_iterator;
+  struct accessor: bi_iterator {
+    accessor(bi_iterator iter) : bi_iterator(iter) {}
+    using bi_iterator::container;
+  };
+  return *accessor(it).container;
+}
+}  // namespace internal
+
+// Formatting context.
+template <typename OutputIt, typename Char>
+class basic_format_context :
+  public internal::context_base<
+    OutputIt, basic_format_context<OutputIt, Char>, Char> {
+ public:
+  /** The character type for the output. */
+  typedef Char char_type;
+
+  // using formatter_type = formatter<T, char_type>;
+  template <typename T>
+  struct formatter_type { typedef formatter<T, char_type> type; };
+
+ private:
+  internal::arg_map<basic_format_context> map_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(basic_format_context);
+
+  typedef internal::context_base<OutputIt, basic_format_context, Char> base;
+  typedef typename base::format_arg format_arg;
+  using base::get_arg;
+
+ public:
+  using typename base::iterator;
+
+  /**
+   Constructs a ``basic_format_context`` object. References to the arguments are
+   stored in the object so make sure they have appropriate lifetimes.
+   */
+  basic_format_context(OutputIt out, basic_string_view<char_type> format_str,
+                basic_format_args<basic_format_context> ctx_args)
+    : base(out, format_str, ctx_args) {}
+
+  format_arg next_arg() {
+    return this->do_get_arg(this->parse_context().next_arg_id());
+  }
+  format_arg get_arg(unsigned arg_id) { return this->do_get_arg(arg_id); }
+
+  // Checks if manual indexing is used and returns the argument with the
+  // specified name.
+  format_arg get_arg(basic_string_view<char_type> name);
+};
+
+template <typename Char>
+struct buffer_context {
+  typedef basic_format_context<
+    std::back_insert_iterator<internal::basic_buffer<Char>>, Char> type;
+};
+typedef buffer_context<char>::type format_context;
+typedef buffer_context<wchar_t>::type wformat_context;
+
+namespace internal {
+template <typename Context, typename T>
+struct get_type {
+  typedef decltype(make_value<Context>(
+        declval<typename std::decay<T>::type&>())) value_type;
+  static const type value = value_type::type_tag;
+};
+
+template <typename Context>
+FMT_CONSTEXPR unsigned long long get_types() { return 0; }
+
+template <typename Context, typename Arg, typename... Args>
+FMT_CONSTEXPR unsigned long long get_types() {
+  return get_type<Context, Arg>::value | (get_types<Context, Args...>() << 4);
+}
+
+template <typename Context, typename T>
+FMT_CONSTEXPR basic_format_arg<Context> make_arg(const T &value) {
+  basic_format_arg<Context> arg;
+  arg.type_ = get_type<Context, T>::value;
+  arg.value_ = make_value<Context>(value);
+  return arg;
+}
+
+template <bool IS_PACKED, typename Context, typename T>
+inline typename std::enable_if<IS_PACKED, value<Context>>::type
+    make_arg(const T &value) {
+  return make_value<Context>(value);
+}
+
+template <bool IS_PACKED, typename Context, typename T>
+inline typename std::enable_if<!IS_PACKED, basic_format_arg<Context>>::type
+    make_arg(const T &value) {
+  return make_arg<Context>(value);
+}
+}
+
+/**
+  \rst
+  An array of references to arguments. It can be implicitly converted into
+  `~fmt::basic_format_args` for passing into type-erased formatting functions
+  such as `~fmt::vformat`.
+  \endrst
+ */
+template <typename Context, typename ...Args>
+class format_arg_store {
+ private:
+  static const size_t NUM_ARGS = sizeof...(Args);
+
+  // Packed is a macro on MinGW so use IS_PACKED instead.
+  static const bool IS_PACKED = NUM_ARGS < internal::max_packed_args;
+
+  typedef typename std::conditional<IS_PACKED,
+    internal::value<Context>, basic_format_arg<Context>>::type value_type;
+
+  // If the arguments are not packed, add one more element to mark the end.
+  static const size_t DATA_SIZE =
+          NUM_ARGS + (IS_PACKED && NUM_ARGS != 0 ? 0 : 1);
+  value_type data_[DATA_SIZE];
+
+  friend class basic_format_args<Context>;
+
+  static FMT_CONSTEXPR long long get_types() {
+    return IS_PACKED ?
+      static_cast<long long>(internal::get_types<Context, Args...>()) :
+      -static_cast<long long>(NUM_ARGS);
+  }
+
+ public:
+#if FMT_USE_CONSTEXPR
+  static constexpr long long TYPES = get_types();
+#else
+  static const long long TYPES;
+#endif
+
+#if (FMT_GCC_VERSION && FMT_GCC_VERSION <= 405) || \
+    (FMT_MSC_VER && FMT_MSC_VER <= 1800)
+  // Workaround array initialization issues in gcc <= 4.5 and MSVC <= 2013.
+  format_arg_store(const Args &... args) {
+    value_type init[DATA_SIZE] =
+      {internal::make_arg<IS_PACKED, Context>(args)...};
+    std::memcpy(data_, init, sizeof(init));
+  }
+#else
+  format_arg_store(const Args &... args)
+    : data_{internal::make_arg<IS_PACKED, Context>(args)...} {}
+#endif
+};
+
+#if !FMT_USE_CONSTEXPR
+template <typename Context, typename ...Args>
+const long long format_arg_store<Context, Args...>::TYPES = get_types();
+#endif
+
+/**
+  \rst
+  Constructs an `~fmt::format_arg_store` object that contains references to
+  arguments and can be implicitly converted to `~fmt::format_args`. `Context` can
+  be omitted in which case it defaults to `~fmt::context`.
+  \endrst
+ */
+template <typename Context, typename ...Args>
+inline format_arg_store<Context, Args...>
+    make_format_args(const Args & ... args) {
+  return format_arg_store<Context, Args...>(args...);
+}
+
+template <typename ...Args>
+inline format_arg_store<format_context, Args...>
+    make_format_args(const Args & ... args) {
+  return format_arg_store<format_context, Args...>(args...);
+}
+
+/** Formatting arguments. */
+template <typename Context>
+class basic_format_args {
+ public:
+  typedef unsigned size_type;
+  typedef basic_format_arg<Context>  format_arg;
+
+ private:
+  // To reduce compiled code size per formatting function call, types of first
+  // max_packed_args arguments are passed in the types_ field.
+  unsigned long long types_;
+  union {
+    // If the number of arguments is less than max_packed_args, the argument
+    // values are stored in values_, otherwise they are stored in args_.
+    // This is done to reduce compiled code size as storing larger objects
+    // may require more code (at least on x86-64) even if the same amount of
+    // data is actually copied to stack. It saves ~10% on the bloat test.
+    const internal::value<Context> *values_;
+    const format_arg *args_;
+  };
+
+  typename internal::type type(unsigned index) const {
+    unsigned shift = index * 4;
+    unsigned long long mask = 0xf;
+    return static_cast<typename internal::type>(
+      (types_ & (mask << shift)) >> shift);
+  }
+
+  friend class internal::arg_map<Context>;
+
+  void set_data(const internal::value<Context> *values) { values_ = values; }
+  void set_data(const format_arg *args) { args_ = args; }
+
+  format_arg do_get(size_type index) const {
+    long long signed_types = static_cast<long long>(types_);
+    if (signed_types < 0) {
+      unsigned long long num_args = static_cast<unsigned long long>(-signed_types);
+      return index < num_args ? args_[index] : format_arg();
+    }
+    format_arg arg;
+    if (index > internal::max_packed_args)
+      return arg;
+    arg.type_ = type(index);
+    if (arg.type_ == internal::none_type)
+      return arg;
+    internal::value<Context> &val = arg.value_;
+    val = values_[index];
+    return arg;
+  }
+
+ public:
+  basic_format_args() : types_(0) {}
+
+  /**
+   \rst
+   Constructs a `basic_format_args` object from `~fmt::format_arg_store`.
+   \endrst
+   */
+  template <typename... Args>
+  basic_format_args(const format_arg_store<Context, Args...> &store)
+  : types_(static_cast<unsigned long long>(store.TYPES)) {
+    set_data(store.data_);
+  }
+
+  /** Returns the argument at specified index. */
+  format_arg get(size_type index) const {
+    format_arg arg = do_get(index);
+    return arg.type_ == internal::named_arg_type ?
+          arg.value_.as_named_arg().template deserialize<Context>() : arg;
+  }
+
+  unsigned max_size() const {
+    long long signed_types = static_cast<long long>(types_);
+    return static_cast<unsigned>(
+        signed_types < 0 ?
+        -signed_types : static_cast<long long>(internal::max_packed_args));
+  }
+};
+
+/** An alias to ``basic_format_args<context>``. */
+// It is a separate type rather than a typedef to make symbols readable.
+struct format_args: basic_format_args<format_context> {
+  template <typename ...Args>
+  format_args(Args && ... arg)
+  : basic_format_args<format_context>(std::forward<Args>(arg)...) {}
+};
+struct wformat_args : basic_format_args<wformat_context> {
+  template <typename ...Args>
+  wformat_args(Args && ... arg)
+  : basic_format_args<wformat_context>(std::forward<Args>(arg)...) {}
+};
+
+namespace internal {
+template <typename Char>
+struct named_arg_base {
+  basic_string_view<Char> name;
+
+  // Serialized value<context>.
+  mutable char data[sizeof(basic_format_arg<format_context>)];
+
+  named_arg_base(basic_string_view<Char> nm) : name(nm) {}
+
+  template <typename Context>
+  basic_format_arg<Context> deserialize() const {
+    basic_format_arg<Context> arg;
+    std::memcpy(&arg, data, sizeof(basic_format_arg<Context>));
+    return arg;
+  }
+};
+
+template <typename T, typename Char>
+struct named_arg : named_arg_base<Char> {
+  const T &value;
+
+  named_arg(basic_string_view<Char> name, const T &val)
+    : named_arg_base<Char>(name), value(val) {}
+};
+}
+
+/**
+  \rst
+  Returns a named argument to be used in a formatting function.
+
+  **Example**::
+
+    fmt::print("Elapsed time: {s:.2f} seconds", fmt::arg("s", 1.23));
+  \endrst
+ */
+template <typename T>
+inline internal::named_arg<T, char> arg(string_view name, const T &arg) {
+  return internal::named_arg<T, char>(name, arg);
+}
+
+template <typename T>
+inline internal::named_arg<T, wchar_t> arg(wstring_view name, const T &arg) {
+  return internal::named_arg<T, wchar_t>(name, arg);
+}
+
+// This function template is deleted intentionally to disable nested named
+// arguments as in ``format("{}", arg("a", arg("b", 42)))``.
+template <typename S, typename T, typename Char>
+void arg(S, internal::named_arg<T, Char>) FMT_DELETED;
+
+#ifndef FMT_EXTENDED_COLORS
+// color and (v)print_colored are deprecated.
+enum color { black, red, green, yellow, blue, magenta, cyan, white };
+FMT_API void vprint_colored(color c, string_view format, format_args args);
+FMT_API void vprint_colored(color c, wstring_view format, wformat_args args);
+template <typename... Args>
+inline void print_colored(color c, string_view format_str,
+                          const Args & ... args) {
+  vprint_colored(c, format_str, make_format_args(args...));
+}
+template <typename... Args>
+inline void print_colored(color c, wstring_view format_str,
+                          const Args & ... args) {
+  vprint_colored(c, format_str, make_format_args<wformat_context>(args...));
+}
+#endif
+
+format_context::iterator vformat_to(
+    internal::buffer &buf, string_view format_str, format_args args);
+wformat_context::iterator vformat_to(
+    internal::wbuffer &buf, wstring_view format_str, wformat_args args);
+
+template <typename Container>
+struct is_contiguous : std::false_type {};
+
+template <typename Char>
+struct is_contiguous<std::basic_string<Char>> : std::true_type {};
+
+template <typename Char>
+struct is_contiguous<internal::basic_buffer<Char>> : std::true_type {};
+
+/** Formats a string and writes the output to ``out``. */
+template <typename Container>
+typename std::enable_if<
+  is_contiguous<Container>::value, std::back_insert_iterator<Container>>::type
+    vformat_to(std::back_insert_iterator<Container> out,
+               string_view format_str, format_args args) {
+  auto& container = internal::get_container(out);
+  internal::container_buffer<Container> buf(container);
+  vformat_to(buf, format_str, args);
+  return std::back_inserter(container);
+}
+
+template <typename Container>
+typename std::enable_if<
+  is_contiguous<Container>::value, std::back_insert_iterator<Container>>::type
+  vformat_to(std::back_insert_iterator<Container> out,
+             wstring_view format_str, wformat_args args) {
+  auto& container = internal::get_container(out);
+  internal::container_buffer<Container> buf(container);
+  vformat_to(buf, format_str, args);
+  return std::back_inserter(container);
+}
+
+std::string vformat(string_view format_str, format_args args);
+std::wstring vformat(wstring_view format_str, wformat_args args);
+
+/**
+  \rst
+  Formats arguments and returns the result as a string.
+
+  **Example**::
+
+    #include <fmt/core.h>
+    std::string message = fmt::format("The answer is {}", 42);
+  \endrst
+*/
+template <typename... Args>
+inline std::string format(string_view format_str, const Args & ... args) {
+  // This should be just
+  // return vformat(format_str, make_format_args(args...));
+  // but gcc has trouble optimizing the latter, so break it down.
+  format_arg_store<format_context, Args...> as{args...};
+  return vformat(format_str, as);
+}
+template <typename... Args>
+inline std::wstring format(wstring_view format_str, const Args & ... args) {
+  format_arg_store<wformat_context, Args...> as{args...};
+  return vformat(format_str, as);
+}
+
+FMT_API void vprint(std::FILE *f, string_view format_str, format_args args);
+FMT_API void vprint(std::FILE *f, wstring_view format_str, wformat_args args);
+
+/**
+  \rst
+  Prints formatted data to the file *f*.
+
+  **Example**::
+
+    fmt::print(stderr, "Don't {}!", "panic");
+  \endrst
+ */
+template <typename... Args>
+inline void print(std::FILE *f, string_view format_str, const Args & ... args) {
+  format_arg_store<format_context, Args...> as(args...);
+  vprint(f, format_str, as);
+}
+/**
+  Prints formatted data to the file *f* which should be in wide-oriented mode set
+  via ``fwide(f, 1)`` or ``_setmode(_fileno(f), _O_U8TEXT)`` on Windows.
+ */
+template <typename... Args>
+inline void print(std::FILE *f, wstring_view format_str, const Args & ... args) {
+  format_arg_store<wformat_context, Args...> as(args...);
+  vprint(f, format_str, as);
+}
+
+FMT_API void vprint(string_view format_str, format_args args);
+FMT_API void vprint(wstring_view format_str, wformat_args args);
+
+/**
+  \rst
+  Prints formatted data to ``stdout``.
+
+  **Example**::
+
+    fmt::print("Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
+ */
+template <typename... Args>
+inline void print(string_view format_str, const Args & ... args) {
+  format_arg_store<format_context, Args...> as{args...};
+  vprint(format_str, as);
+}
+
+template <typename... Args>
+inline void print(wstring_view format_str, const Args & ... args) {
+  format_arg_store<wformat_context, Args...> as(args...);
+  vprint(format_str, as);
+}
+FMT_END_NAMESPACE
+
+#endif  // FMT_CORE_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/format-inl.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,564 @@
+// Formatting library for C++
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_FORMAT_INL_H_
+#define FMT_FORMAT_INL_H_
+
+#include "format.h"
+
+#include <string.h>
+
+#include <cctype>
+#include <cerrno>
+#include <climits>
+#include <cmath>
+#include <cstdarg>
+#include <cstddef>  // for std::ptrdiff_t
+#include <locale>
+
+#if defined(_WIN32) && defined(__MINGW32__)
+# include <cstring>
+#endif
+
+#if FMT_USE_WINDOWS_H
+# if !defined(FMT_HEADER_ONLY) && !defined(WIN32_LEAN_AND_MEAN)
+#  define WIN32_LEAN_AND_MEAN
+# endif
+# if defined(NOMINMAX) || defined(FMT_WIN_MINMAX)
+#  include <windows.h>
+# else
+#  define NOMINMAX
+#  include <windows.h>
+#  undef NOMINMAX
+# endif
+#endif
+
+#if FMT_EXCEPTIONS
+# define FMT_TRY try
+# define FMT_CATCH(x) catch (x)
+#else
+# define FMT_TRY if (true)
+# define FMT_CATCH(x) if (false)
+#endif
+
+#ifdef _MSC_VER
+# pragma warning(push)
+# pragma warning(disable: 4127)  // conditional expression is constant
+# pragma warning(disable: 4702)  // unreachable code
+// Disable deprecation warning for strerror. The latter is not called but
+// MSVC fails to detect it.
+# pragma warning(disable: 4996)
+#endif
+
+// Dummy implementations of strerror_r and strerror_s called if corresponding
+// system functions are not available.
+inline fmt::internal::null<> strerror_r(int, char *, ...) {
+  return fmt::internal::null<>();
+}
+inline fmt::internal::null<> strerror_s(char *, std::size_t, ...) {
+  return fmt::internal::null<>();
+}
+
+FMT_BEGIN_NAMESPACE
+
+namespace {
+
+#ifndef _MSC_VER
+# define FMT_SNPRINTF snprintf
+#else  // _MSC_VER
+inline int fmt_snprintf(char *buffer, size_t size, const char *format, ...) {
+  va_list args;
+  va_start(args, format);
+  int result = vsnprintf_s(buffer, size, _TRUNCATE, format, args);
+  va_end(args);
+  return result;
+}
+# define FMT_SNPRINTF fmt_snprintf
+#endif  // _MSC_VER
+
+#if defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
+# define FMT_SWPRINTF snwprintf
+#else
+# define FMT_SWPRINTF swprintf
+#endif // defined(_WIN32) && defined(__MINGW32__) && !defined(__NO_ISOCEXT)
+
+typedef void (*FormatFunc)(internal::buffer &, int, string_view);
+
+// Portable thread-safe version of strerror.
+// Sets buffer to point to a string describing the error code.
+// This can be either a pointer to a string stored in buffer,
+// or a pointer to some static immutable string.
+// Returns one of the following values:
+//   0      - success
+//   ERANGE - buffer is not large enough to store the error message
+//   other  - failure
+// Buffer should be at least of size 1.
+int safe_strerror(
+    int error_code, char *&buffer, std::size_t buffer_size) FMT_NOEXCEPT {
+  FMT_ASSERT(buffer != FMT_NULL && buffer_size != 0, "invalid buffer");
+
+  class dispatcher {
+   private:
+    int error_code_;
+    char *&buffer_;
+    std::size_t buffer_size_;
+
+    // A noop assignment operator to avoid bogus warnings.
+    void operator=(const dispatcher &) {}
+
+    // Handle the result of XSI-compliant version of strerror_r.
+    int handle(int result) {
+      // glibc versions before 2.13 return result in errno.
+      return result == -1 ? errno : result;
+    }
+
+    // Handle the result of GNU-specific version of strerror_r.
+    int handle(char *message) {
+      // If the buffer is full then the message is probably truncated.
+      if (message == buffer_ && strlen(buffer_) == buffer_size_ - 1)
+        return ERANGE;
+      buffer_ = message;
+      return 0;
+    }
+
+    // Handle the case when strerror_r is not available.
+    int handle(internal::null<>) {
+      return fallback(strerror_s(buffer_, buffer_size_, error_code_));
+    }
+
+    // Fallback to strerror_s when strerror_r is not available.
+    int fallback(int result) {
+      // If the buffer is full then the message is probably truncated.
+      return result == 0 && strlen(buffer_) == buffer_size_ - 1 ?
+            ERANGE : result;
+    }
+
+    // Fallback to strerror if strerror_r and strerror_s are not available.
+    int fallback(internal::null<>) {
+      errno = 0;
+      buffer_ = strerror(error_code_);
+      return errno;
+    }
+
+   public:
+    dispatcher(int err_code, char *&buf, std::size_t buf_size)
+      : error_code_(err_code), buffer_(buf), buffer_size_(buf_size) {}
+
+    int run() {
+      return handle(strerror_r(error_code_, buffer_, buffer_size_));
+    }
+  };
+  return dispatcher(error_code, buffer, buffer_size).run();
+}
+
+void format_error_code(internal::buffer &out, int error_code,
+                       string_view message) FMT_NOEXCEPT {
+  // Report error code making sure that the output fits into
+  // inline_buffer_size to avoid dynamic memory allocation and potential
+  // bad_alloc.
+  out.resize(0);
+  static const char SEP[] = ": ";
+  static const char ERROR_STR[] = "error ";
+  // Subtract 2 to account for terminating null characters in SEP and ERROR_STR.
+  std::size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
+  typedef internal::int_traits<int>::main_type main_type;
+  main_type abs_value = static_cast<main_type>(error_code);
+  if (internal::is_negative(error_code)) {
+    abs_value = 0 - abs_value;
+    ++error_code_size;
+  }
+  error_code_size += internal::count_digits(abs_value);
+  writer w(out);
+  if (message.size() <= inline_buffer_size - error_code_size) {
+    w.write(message);
+    w.write(SEP);
+  }
+  w.write(ERROR_STR);
+  w.write(error_code);
+  assert(out.size() <= inline_buffer_size);
+}
+
+void report_error(FormatFunc func, int error_code,
+                  string_view message) FMT_NOEXCEPT {
+  memory_buffer full_message;
+  func(full_message, error_code, message);
+  // Use Writer::data instead of Writer::c_str to avoid potential memory
+  // allocation.
+  std::fwrite(full_message.data(), full_message.size(), 1, stderr);
+  std::fputc('\n', stderr);
+}
+}  // namespace
+
+class locale {
+ private:
+  std::locale locale_;
+
+ public:
+  explicit locale(std::locale loc = std::locale()) : locale_(loc) {}
+  std::locale get() { return locale_; }
+};
+
+template <typename Char>
+FMT_FUNC Char internal::thousands_sep(locale_provider *lp) {
+  std::locale loc = lp ? lp->locale().get() : std::locale();
+  return std::use_facet<std::numpunct<Char>>(loc).thousands_sep();
+}
+
+FMT_FUNC void system_error::init(
+    int err_code, string_view format_str, format_args args) {
+  error_code_ = err_code;
+  memory_buffer buffer;
+  format_system_error(buffer, err_code, vformat(format_str, args));
+  std::runtime_error &base = *this;
+  base = std::runtime_error(to_string(buffer));
+}
+
+namespace internal {
+template <typename T>
+int char_traits<char>::format_float(
+    char *buffer, std::size_t size, const char *format, int precision, T value) {
+  return precision < 0 ?
+      FMT_SNPRINTF(buffer, size, format, value) :
+      FMT_SNPRINTF(buffer, size, format, precision, value);
+}
+
+template <typename T>
+int char_traits<wchar_t>::format_float(
+    wchar_t *buffer, std::size_t size, const wchar_t *format, int precision,
+    T value) {
+  return precision < 0 ?
+      FMT_SWPRINTF(buffer, size, format, value) :
+      FMT_SWPRINTF(buffer, size, format, precision, value);
+}
+
+template <typename T>
+const char basic_data<T>::DIGITS[] =
+    "0001020304050607080910111213141516171819"
+    "2021222324252627282930313233343536373839"
+    "4041424344454647484950515253545556575859"
+    "6061626364656667686970717273747576777879"
+    "8081828384858687888990919293949596979899";
+
+#define FMT_POWERS_OF_10(factor) \
+  factor * 10, \
+  factor * 100, \
+  factor * 1000, \
+  factor * 10000, \
+  factor * 100000, \
+  factor * 1000000, \
+  factor * 10000000, \
+  factor * 100000000, \
+  factor * 1000000000
+
+template <typename T>
+const uint32_t basic_data<T>::POWERS_OF_10_32[] = {
+  0, FMT_POWERS_OF_10(1)
+};
+
+template <typename T>
+const uint64_t basic_data<T>::POWERS_OF_10_64[] = {
+  0,
+  FMT_POWERS_OF_10(1),
+  FMT_POWERS_OF_10(1000000000ull),
+  10000000000000000000ull
+};
+
+// Normalized 64-bit significands of pow(10, k), for k = -348, -340, ..., 340.
+// These are generated by support/compute-powers.py.
+template <typename T>
+const uint64_t basic_data<T>::POW10_SIGNIFICANDS[] = {
+  0xfa8fd5a0081c0288, 0xbaaee17fa23ebf76, 0x8b16fb203055ac76, 0xcf42894a5dce35ea,
+  0x9a6bb0aa55653b2d, 0xe61acf033d1a45df, 0xab70fe17c79ac6ca, 0xff77b1fcbebcdc4f,
+  0xbe5691ef416bd60c, 0x8dd01fad907ffc3c, 0xd3515c2831559a83, 0x9d71ac8fada6c9b5,
+  0xea9c227723ee8bcb, 0xaecc49914078536d, 0x823c12795db6ce57, 0xc21094364dfb5637,
+  0x9096ea6f3848984f, 0xd77485cb25823ac7, 0xa086cfcd97bf97f4, 0xef340a98172aace5,
+  0xb23867fb2a35b28e, 0x84c8d4dfd2c63f3b, 0xc5dd44271ad3cdba, 0x936b9fcebb25c996,
+  0xdbac6c247d62a584, 0xa3ab66580d5fdaf6, 0xf3e2f893dec3f126, 0xb5b5ada8aaff80b8,
+  0x87625f056c7c4a8b, 0xc9bcff6034c13053, 0x964e858c91ba2655, 0xdff9772470297ebd,
+  0xa6dfbd9fb8e5b88f, 0xf8a95fcf88747d94, 0xb94470938fa89bcf, 0x8a08f0f8bf0f156b,
+  0xcdb02555653131b6, 0x993fe2c6d07b7fac, 0xe45c10c42a2b3b06, 0xaa242499697392d3,
+  0xfd87b5f28300ca0e, 0xbce5086492111aeb, 0x8cbccc096f5088cc, 0xd1b71758e219652c,
+  0x9c40000000000000, 0xe8d4a51000000000, 0xad78ebc5ac620000, 0x813f3978f8940984,
+  0xc097ce7bc90715b3, 0x8f7e32ce7bea5c70, 0xd5d238a4abe98068, 0x9f4f2726179a2245,
+  0xed63a231d4c4fb27, 0xb0de65388cc8ada8, 0x83c7088e1aab65db, 0xc45d1df942711d9a,
+  0x924d692ca61be758, 0xda01ee641a708dea, 0xa26da3999aef774a, 0xf209787bb47d6b85,
+  0xb454e4a179dd1877, 0x865b86925b9bc5c2, 0xc83553c5c8965d3d, 0x952ab45cfa97a0b3,
+  0xde469fbd99a05fe3, 0xa59bc234db398c25, 0xf6c69a72a3989f5c, 0xb7dcbf5354e9bece,
+  0x88fcf317f22241e2, 0xcc20ce9bd35c78a5, 0x98165af37b2153df, 0xe2a0b5dc971f303a,
+  0xa8d9d1535ce3b396, 0xfb9b7cd9a4a7443c, 0xbb764c4ca7a44410, 0x8bab8eefb6409c1a,
+  0xd01fef10a657842c, 0x9b10a4e5e9913129, 0xe7109bfba19c0c9d, 0xac2820d9623bf429,
+  0x80444b5e7aa7cf85, 0xbf21e44003acdd2d, 0x8e679c2f5e44ff8f, 0xd433179d9c8cb841,
+  0x9e19db92b4e31ba9, 0xeb96bf6ebadf77d9, 0xaf87023b9bf0ee6b
+};
+
+// Binary exponents of pow(10, k), for k = -348, -340, ..., 340, corresponding
+// to significands above.
+template <typename T>
+const int16_t basic_data<T>::POW10_EXPONENTS[] = {
+  -1220, -1193, -1166, -1140, -1113, -1087, -1060, -1034, -1007,  -980,  -954,
+   -927,  -901,  -874,  -847,  -821,  -794,  -768,  -741,  -715,  -688,  -661,
+   -635,  -608,  -582,  -555,  -529,  -502,  -475,  -449,  -422,  -396,  -369,
+   -343,  -316,  -289,  -263,  -236,  -210,  -183,  -157,  -130,  -103,   -77,
+    -50,   -24,     3,    30,    56,    83,   109,   136,   162,   189,   216,
+    242,   269,   295,   322,   348,   375,   402,   428,   455,   481,   508,
+    534,   561,   588,   614,   641,   667,   694,   720,   747,   774,   800,
+    827,   853,   880,   907,   933,   960,   986,  1013,  1039,  1066
+};
+
+template <typename T> const char basic_data<T>::RESET_COLOR[] = "\x1b[0m";
+template <typename T> const wchar_t basic_data<T>::WRESET_COLOR[] = L"\x1b[0m";
+
+FMT_FUNC fp operator*(fp x, fp y) {
+  // Multiply 32-bit parts of significands.
+  uint64_t mask = (1ULL << 32) - 1;
+  uint64_t a = x.f >> 32, b = x.f & mask;
+  uint64_t c = y.f >> 32, d = y.f & mask;
+  uint64_t ac = a * c, bc = b * c, ad = a * d, bd = b * d;
+  // Compute mid 64-bit of result and round.
+  uint64_t mid = (bd >> 32) + (ad & mask) + (bc & mask) + (1U << 31);
+  return fp(ac + (ad >> 32) + (bc >> 32) + (mid >> 32), x.e + y.e + 64);
+}
+
+FMT_FUNC fp get_cached_power(int min_exponent, int &pow10_exponent) {
+  const double one_over_log2_10 = 0.30102999566398114;  // 1 / log2(10)
+  int index = static_cast<int>(std::ceil(
+        (min_exponent + fp::significand_size - 1) * one_over_log2_10));
+  // Decimal exponent of the first (smallest) cached power of 10.
+  const int first_dec_exp = -348;
+  // Difference between two consecutive decimal exponents in cached powers of 10.
+  const int dec_exp_step = 8;
+  index = (index - first_dec_exp - 1) / dec_exp_step + 1;
+  pow10_exponent = first_dec_exp + index * dec_exp_step;
+  return fp(data::POW10_SIGNIFICANDS[index], data::POW10_EXPONENTS[index]);
+}
+}  // namespace internal
+
+#if FMT_USE_WINDOWS_H
+
+FMT_FUNC internal::utf8_to_utf16::utf8_to_utf16(string_view s) {
+  static const char ERROR_MSG[] = "cannot convert string from UTF-8 to UTF-16";
+  if (s.size() > INT_MAX)
+    FMT_THROW(windows_error(ERROR_INVALID_PARAMETER, ERROR_MSG));
+  int s_size = static_cast<int>(s.size());
+  if (s_size == 0) {
+    // MultiByteToWideChar does not support zero length, handle separately.
+    buffer_.resize(1);
+    buffer_[0] = 0;
+    return;
+  }
+
+  int length = MultiByteToWideChar(
+      CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, FMT_NULL, 0);
+  if (length == 0)
+    FMT_THROW(windows_error(GetLastError(), ERROR_MSG));
+  buffer_.resize(length + 1);
+  length = MultiByteToWideChar(
+    CP_UTF8, MB_ERR_INVALID_CHARS, s.data(), s_size, &buffer_[0], length);
+  if (length == 0)
+    FMT_THROW(windows_error(GetLastError(), ERROR_MSG));
+  buffer_[length] = 0;
+}
+
+FMT_FUNC internal::utf16_to_utf8::utf16_to_utf8(wstring_view s) {
+  if (int error_code = convert(s)) {
+    FMT_THROW(windows_error(error_code,
+        "cannot convert string from UTF-16 to UTF-8"));
+  }
+}
+
+FMT_FUNC int internal::utf16_to_utf8::convert(wstring_view s) {
+  if (s.size() > INT_MAX)
+    return ERROR_INVALID_PARAMETER;
+  int s_size = static_cast<int>(s.size());
+  if (s_size == 0) {
+    // WideCharToMultiByte does not support zero length, handle separately.
+    buffer_.resize(1);
+    buffer_[0] = 0;
+    return 0;
+  }
+
+  int length = WideCharToMultiByte(
+        CP_UTF8, 0, s.data(), s_size, FMT_NULL, 0, FMT_NULL, FMT_NULL);
+  if (length == 0)
+    return GetLastError();
+  buffer_.resize(length + 1);
+  length = WideCharToMultiByte(
+    CP_UTF8, 0, s.data(), s_size, &buffer_[0], length, FMT_NULL, FMT_NULL);
+  if (length == 0)
+    return GetLastError();
+  buffer_[length] = 0;
+  return 0;
+}
+
+FMT_FUNC void windows_error::init(
+    int err_code, string_view format_str, format_args args) {
+  error_code_ = err_code;
+  memory_buffer buffer;
+  internal::format_windows_error(buffer, err_code, vformat(format_str, args));
+  std::runtime_error &base = *this;
+  base = std::runtime_error(to_string(buffer));
+}
+
+FMT_FUNC void internal::format_windows_error(
+    internal::buffer &out, int error_code, string_view message) FMT_NOEXCEPT {
+  FMT_TRY {
+    wmemory_buffer buf;
+    buf.resize(inline_buffer_size);
+    for (;;) {
+      wchar_t *system_message = &buf[0];
+      int result = FormatMessageW(
+          FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+          FMT_NULL, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+          system_message, static_cast<uint32_t>(buf.size()), FMT_NULL);
+      if (result != 0) {
+        utf16_to_utf8 utf8_message;
+        if (utf8_message.convert(system_message) == ERROR_SUCCESS) {
+          writer w(out);
+          w.write(message);
+          w.write(": ");
+          w.write(utf8_message);
+          return;
+        }
+        break;
+      }
+      if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+        break;  // Can't get error message, report error code instead.
+      buf.resize(buf.size() * 2);
+    }
+  } FMT_CATCH(...) {}
+  format_error_code(out, error_code, message);
+}
+
+#endif  // FMT_USE_WINDOWS_H
+
+FMT_FUNC void format_system_error(
+    internal::buffer &out, int error_code, string_view message) FMT_NOEXCEPT {
+  FMT_TRY {
+    memory_buffer buf;
+    buf.resize(inline_buffer_size);
+    for (;;) {
+      char *system_message = &buf[0];
+      int result = safe_strerror(error_code, system_message, buf.size());
+      if (result == 0) {
+        writer w(out);
+        w.write(message);
+        w.write(": ");
+        w.write(system_message);
+        return;
+      }
+      if (result != ERANGE)
+        break;  // Can't get error message, report error code instead.
+      buf.resize(buf.size() * 2);
+    }
+  } FMT_CATCH(...) {}
+  format_error_code(out, error_code, message);
+}
+
+template <typename Char>
+void basic_fixed_buffer<Char>::grow(std::size_t) {
+  FMT_THROW(std::runtime_error("buffer overflow"));
+}
+
+FMT_FUNC void internal::error_handler::on_error(const char *message) {
+  FMT_THROW(format_error(message));
+}
+
+FMT_FUNC void report_system_error(
+    int error_code, fmt::string_view message) FMT_NOEXCEPT {
+  report_error(format_system_error, error_code, message);
+}
+
+#if FMT_USE_WINDOWS_H
+FMT_FUNC void report_windows_error(
+    int error_code, fmt::string_view message) FMT_NOEXCEPT {
+  report_error(internal::format_windows_error, error_code, message);
+}
+#endif
+
+FMT_FUNC void vprint(std::FILE *f, string_view format_str, format_args args) {
+  memory_buffer buffer;
+  vformat_to(buffer, format_str, args);
+  std::fwrite(buffer.data(), 1, buffer.size(), f);
+}
+
+FMT_FUNC void vprint(std::FILE *f, wstring_view format_str, wformat_args args) {
+  wmemory_buffer buffer;
+  vformat_to(buffer, format_str, args);
+  std::fwrite(buffer.data(), sizeof(wchar_t), buffer.size(), f);
+}
+
+FMT_FUNC void vprint(string_view format_str, format_args args) {
+  vprint(stdout, format_str, args);
+}
+
+FMT_FUNC void vprint(wstring_view format_str, wformat_args args) {
+  vprint(stdout, format_str, args);
+}
+
+#ifndef FMT_EXTENDED_COLORS
+FMT_FUNC void vprint_colored(color c, string_view format, format_args args) {
+  char escape[] = "\x1b[30m";
+  escape[3] = static_cast<char>('0' + c);
+  std::fputs(escape, stdout);
+  vprint(format, args);
+  std::fputs(internal::data::RESET_COLOR, stdout);
+}
+
+FMT_FUNC void vprint_colored(color c, wstring_view format, wformat_args args) {
+  wchar_t escape[] = L"\x1b[30m";
+  escape[3] = static_cast<wchar_t>('0' + c);
+  std::fputws(escape, stdout);
+  vprint(format, args);
+  std::fputws(internal::data::WRESET_COLOR, stdout);
+}
+#else
+namespace internal {
+FMT_CONSTEXPR void to_esc(uint8_t c, char out[], int offset) {
+  out[offset + 0] = static_cast<char>('0' + c / 100);
+  out[offset + 1] = static_cast<char>('0' + c / 10 % 10);
+  out[offset + 2] = static_cast<char>('0' + c % 10);
+}
+} // namespace internal
+
+FMT_FUNC void vprint_rgb(rgb fd, string_view format, format_args args) {
+  char escape_fd[] = "\x1b[38;2;000;000;000m";
+  internal::to_esc(fd.r, escape_fd, 7);
+  internal::to_esc(fd.g, escape_fd, 11);
+  internal::to_esc(fd.b, escape_fd, 15);
+
+  std::fputs(escape_fd, stdout);
+  vprint(format, args);
+  std::fputs(internal::data::RESET_COLOR, stdout);
+}
+
+FMT_FUNC void vprint_rgb(rgb fd, rgb bg, string_view format, format_args args) {
+  char escape_fd[] = "\x1b[38;2;000;000;000m"; // foreground color
+  char escape_bg[] = "\x1b[48;2;000;000;000m"; // background color
+  internal::to_esc(fd.r, escape_fd, 7);
+  internal::to_esc(fd.g, escape_fd, 11);
+  internal::to_esc(fd.b, escape_fd, 15);
+
+  internal::to_esc(bg.r, escape_bg, 7);
+  internal::to_esc(bg.g, escape_bg, 11);
+  internal::to_esc(bg.b, escape_bg, 15);
+
+  std::fputs(escape_fd, stdout);
+  std::fputs(escape_bg, stdout);
+  vprint(format, args);
+  std::fputs(internal::data::RESET_COLOR, stdout);
+}
+#endif
+
+FMT_FUNC locale locale_provider::locale() { return fmt::locale(); }
+
+FMT_END_NAMESPACE
+
+#ifdef _MSC_VER
+# pragma warning(pop)
+#endif
+
+#endif  // FMT_FORMAT_INL_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/format.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,3937 @@
+/*
+ Formatting library for C++
+
+ Copyright (c) 2012 - present, Victor Zverovich
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this
+    list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef FMT_FORMAT_H_
+#define FMT_FORMAT_H_
+
+#include <algorithm>
+#include <cassert>
+#include <cmath>
+#include <cstring>
+#include <limits>
+#include <memory>
+#include <stdexcept>
+#include <stdint.h>
+
+#ifdef __clang__
+# define FMT_CLANG_VERSION (__clang_major__ * 100 + __clang_minor__)
+#else
+# define FMT_CLANG_VERSION 0
+#endif
+
+#ifdef __INTEL_COMPILER
+# define FMT_ICC_VERSION __INTEL_COMPILER
+#elif defined(__ICL)
+# define FMT_ICC_VERSION __ICL
+#else
+# define FMT_ICC_VERSION 0
+#endif
+
+#include "core.h"
+
+#if FMT_GCC_VERSION >= 406 || FMT_CLANG_VERSION
+# pragma GCC diagnostic push
+
+// Disable the warning about declaration shadowing because it affects too
+// many valid cases.
+# pragma GCC diagnostic ignored "-Wshadow"
+
+// Disable the warning about implicit conversions that may change the sign of
+// an integer; silencing it otherwise would require many explicit casts.
+# pragma GCC diagnostic ignored "-Wsign-conversion"
+#endif
+
+#ifdef _SECURE_SCL
+# define FMT_SECURE_SCL _SECURE_SCL
+#else
+# define FMT_SECURE_SCL 0
+#endif
+
+#if FMT_SECURE_SCL
+# include <iterator>
+#endif
+
+#ifdef __has_builtin
+# define FMT_HAS_BUILTIN(x) __has_builtin(x)
+#else
+# define FMT_HAS_BUILTIN(x) 0
+#endif
+
+#ifdef __GNUC_LIBSTD__
+# define FMT_GNUC_LIBSTD_VERSION (__GNUC_LIBSTD__ * 100 + __GNUC_LIBSTD_MINOR__)
+#endif
+
+#ifndef FMT_THROW
+# if FMT_EXCEPTIONS
+#  if FMT_MSC_VER
+FMT_BEGIN_NAMESPACE
+namespace internal {
+template <typename Exception>
+inline void do_throw(const Exception &x) {
+  // Silence unreachable code warnings in MSVC because these are nearly
+  // impossible to fix in a generic code.
+  volatile bool b = true;
+  if (b)
+    throw x;
+}
+}
+FMT_END_NAMESPACE
+#   define FMT_THROW(x) fmt::internal::do_throw(x)
+#  else
+#   define FMT_THROW(x) throw x
+#  endif
+# else
+#  define FMT_THROW(x) do { static_cast<void>(sizeof(x)); assert(false); } while(false);
+# endif
+#endif
+
+#ifndef FMT_USE_USER_DEFINED_LITERALS
+// For Intel's compiler both it and the system gcc/msc must support UDLs.
+# if (FMT_HAS_FEATURE(cxx_user_literals) || \
+      FMT_GCC_VERSION >= 407 || FMT_MSC_VER >= 1900) && \
+      (!FMT_ICC_VERSION || FMT_ICC_VERSION >= 1500)
+#  define FMT_USE_USER_DEFINED_LITERALS 1
+# else
+#  define FMT_USE_USER_DEFINED_LITERALS 0
+# endif
+#endif
+
+#if FMT_USE_USER_DEFINED_LITERALS && !defined(FMT_ICC_VERSION) && \
+    ((FMT_GCC_VERSION >= 600 && __cplusplus >= 201402L) || \
+    (defined(FMT_CLANG_VERSION) && FMT_CLANG_VERSION >= 304))
+# define FMT_UDL_TEMPLATE 1
+#else
+# define FMT_UDL_TEMPLATE 0
+#endif
+
+#ifndef FMT_USE_EXTERN_TEMPLATES
+# ifndef FMT_HEADER_ONLY
+#  define FMT_USE_EXTERN_TEMPLATES \
+     ((FMT_CLANG_VERSION >= 209 && __cplusplus >= 201103L) || \
+      (FMT_GCC_VERSION >= 303 && FMT_HAS_GXX_CXX11))
+# else
+#  define FMT_USE_EXTERN_TEMPLATES 0
+# endif
+#endif
+
+#if FMT_HAS_GXX_CXX11 || FMT_HAS_FEATURE(cxx_trailing_return) || \
+    FMT_MSC_VER >= 1600
+# define FMT_USE_TRAILING_RETURN 1
+#else
+# define FMT_USE_TRAILING_RETURN 0
+#endif
+
+#if FMT_HAS_GXX_CXX11 || FMT_HAS_FEATURE(cxx_rvalue_references) || \
+    FMT_MSC_VER >= 1600
+# define FMT_USE_RVALUE_REFERENCES 1
+#else
+# define FMT_USE_RVALUE_REFERENCES 0
+#endif
+
+#ifndef FMT_USE_GRISU
+# define FMT_USE_GRISU 0
+#endif
+
+// __builtin_clz is broken in clang with Microsoft CodeGen:
+// https://github.com/fmtlib/fmt/issues/519
+#ifndef _MSC_VER
+# if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__builtin_clz)
+#  define FMT_BUILTIN_CLZ(n) __builtin_clz(n)
+# endif
+
+# if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__builtin_clzll)
+#  define FMT_BUILTIN_CLZLL(n) __builtin_clzll(n)
+# endif
+#endif
+
+// A workaround for gcc 4.4 that doesn't support union members with ctors.
+#if (FMT_GCC_VERSION && FMT_GCC_VERSION <= 404) || \
+    (FMT_MSC_VER && FMT_MSC_VER <= 1800)
+# define FMT_UNION struct
+#else
+# define FMT_UNION union
+#endif
+
+// Some compilers masquerade as both MSVC and GCC-likes or otherwise support
+// __builtin_clz and __builtin_clzll, so only define FMT_BUILTIN_CLZ using the
+// MSVC intrinsics if the clz and clzll builtins are not available.
+#if FMT_MSC_VER && !defined(FMT_BUILTIN_CLZLL) && !defined(_MANAGED)
+# include <intrin.h>  // _BitScanReverse, _BitScanReverse64
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+// Avoid Clang with Microsoft CodeGen's -Wunknown-pragmas warning.
+# ifndef __clang__
+#  pragma intrinsic(_BitScanReverse)
+# endif
+inline uint32_t clz(uint32_t x) {
+  unsigned long r = 0;
+  _BitScanReverse(&r, x);
+
+  assert(x != 0);
+  // Static analysis complains about using uninitialized data
+  // "r", but the only way that can happen is if "x" is 0,
+  // which the callers guarantee to not happen.
+# pragma warning(suppress: 6102)
+  return 31 - r;
+}
+# define FMT_BUILTIN_CLZ(n) fmt::internal::clz(n)
+
+# if defined(_WIN64) && !defined(__clang__)
+#  pragma intrinsic(_BitScanReverse64)
+# endif
+
+inline uint32_t clzll(uint64_t x) {
+  unsigned long r = 0;
+# ifdef _WIN64
+  _BitScanReverse64(&r, x);
+# else
+  // Scan the high 32 bits.
+  if (_BitScanReverse(&r, static_cast<uint32_t>(x >> 32)))
+    return 63 - (r + 32);
+
+  // Scan the low 32 bits.
+  _BitScanReverse(&r, static_cast<uint32_t>(x));
+# endif
+
+  assert(x != 0);
+  // Static analysis complains about using uninitialized data
+  // "r", but the only way that can happen is if "x" is 0,
+  // which the callers guarantee to not happen.
+# pragma warning(suppress: 6102)
+  return 63 - r;
+}
+# define FMT_BUILTIN_CLZLL(n) fmt::internal::clzll(n)
+}
+FMT_END_NAMESPACE
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+
+// An equivalent of `*reinterpret_cast<Dest*>(&source)` that doesn't produce
+// undefined behavior (e.g. due to type aliasing).
+// Example: uint64_t d = bit_cast<uint64_t>(2.718);
+template <typename Dest, typename Source>
+inline Dest bit_cast(const Source& source) {
+  static_assert(sizeof(Dest) == sizeof(Source), "size mismatch");
+  Dest dest;
+  std::memcpy(&dest, &source, sizeof(dest));
+  return dest;
+}
+
+// An implementation of begin and end for pre-C++11 compilers such as gcc 4.
+template <typename C>
+FMT_CONSTEXPR auto begin(const C &c) -> decltype(c.begin()) {
+  return c.begin();
+}
+template <typename T, std::size_t N>
+FMT_CONSTEXPR T *begin(T (&array)[N]) FMT_NOEXCEPT { return array; }
+template <typename C>
+FMT_CONSTEXPR auto end(const C &c) -> decltype(c.end()) { return c.end(); }
+template <typename T, std::size_t N>
+FMT_CONSTEXPR T *end(T (&array)[N]) FMT_NOEXCEPT { return array + N; }
+
+// For std::result_of in gcc 4.4.
+template <typename Result>
+struct function {
+  template <typename T>
+  struct result { typedef Result type; };
+};
+
+struct dummy_int {
+  int data[2];
+  operator int() const { return 0; }
+};
+typedef std::numeric_limits<internal::dummy_int> fputil;
+
+// Dummy implementations of system functions such as signbit and ecvt called
+// if the latter are not available.
+inline dummy_int signbit(...) { return dummy_int(); }
+inline dummy_int _ecvt_s(...) { return dummy_int(); }
+inline dummy_int isinf(...) { return dummy_int(); }
+inline dummy_int _finite(...) { return dummy_int(); }
+inline dummy_int isnan(...) { return dummy_int(); }
+inline dummy_int _isnan(...) { return dummy_int(); }
+
+// A handmade floating-point number f * pow(2, e).
+class fp {
+ private:
+  typedef uint64_t significand_type;
+
+  // All sizes are in bits.
+  static FMT_CONSTEXPR_DECL const int char_size =
+    std::numeric_limits<unsigned char>::digits;
+  // Subtract 1 to account for an implicit most significant bit in the
+  // normalized form.
+  static FMT_CONSTEXPR_DECL const int double_significand_size =
+    std::numeric_limits<double>::digits - 1;
+  static FMT_CONSTEXPR_DECL const uint64_t implicit_bit =
+    1ull << double_significand_size;
+
+ public:
+  significand_type f;
+  int e;
+
+  static FMT_CONSTEXPR_DECL const int significand_size =
+    sizeof(significand_type) * char_size;
+
+  fp(uint64_t f, int e): f(f), e(e) {}
+
+  // Constructs fp from an IEEE754 double. It is a template to prevent compile
+  // errors on platforms where double is not IEEE754.
+  template <typename Double>
+  explicit fp(Double d) {
+    // Assume double is in the format [sign][exponent][significand].
+    typedef std::numeric_limits<Double> limits;
+    const int double_size = sizeof(Double) * char_size;
+    const int exponent_size =
+      double_size - double_significand_size - 1;  // -1 for sign
+    const uint64_t significand_mask = implicit_bit - 1;
+    const uint64_t exponent_mask = (~0ull >> 1) & ~significand_mask;
+    const int exponent_bias = (1 << exponent_size) - limits::max_exponent - 1;
+    auto u = bit_cast<uint64_t>(d);
+    auto biased_e = (u & exponent_mask) >> double_significand_size;
+    f = u & significand_mask;
+    if (biased_e != 0)
+      f += implicit_bit;
+    else
+      biased_e = 1;  // Subnormals use biased exponent 1 (min exponent).
+    e = static_cast<int>(biased_e - exponent_bias - double_significand_size);
+  }
+
+  // Normalizes the value converted from double and multiplied by (1 << SHIFT).
+  template <int SHIFT = 0>
+  void normalize() {
+    // Handle subnormals.
+    auto shifted_implicit_bit = implicit_bit << SHIFT;
+    while ((f & shifted_implicit_bit) == 0) {
+      f <<= 1;
+      --e;
+    }
+    // Subtract 1 to account for hidden bit.
+    auto offset = significand_size - double_significand_size - SHIFT - 1;
+    f <<= offset;
+    e -= offset;
+  }
+};
+
+// Returns an fp number representing x - y. Result may not be normalized.
+inline fp operator-(fp x, fp y) {
+  FMT_ASSERT(x.f >= y.f && x.e == y.e, "invalid operands");
+  return fp(x.f - y.f, x.e);
+}
+
+// Computes an fp number r with r.f = x.f * y.f / pow(2, 64) rounded to nearest
+// with half-up tie breaking, r.e = x.e + y.e + 64. Result may not be normalized.
+fp operator*(fp x, fp y);
+
+// Returns cached power (of 10) c_k = c_k.f * pow(2, c_k.e) such that its
+// (binary) exponent satisfies min_exponent <= c_k.e <= min_exponent + 3.
+fp get_cached_power(int min_exponent, int &pow10_exponent);
+
+template <typename Allocator>
+typename Allocator::value_type *allocate(Allocator& alloc, std::size_t n) {
+#if __cplusplus >= 201103L || FMT_MSC_VER >= 1700
+  return std::allocator_traits<Allocator>::allocate(alloc, n);
+#else
+  return alloc.allocate(n);
+#endif
+}
+
+// A helper function to suppress bogus "conditional expression is constant"
+// warnings.
+template <typename T>
+inline T const_check(T value) { return value; }
+}  // namespace internal
+FMT_END_NAMESPACE
+
+namespace std {
+// Standard permits specialization of std::numeric_limits. This specialization
+// is used to resolve ambiguity between isinf and std::isinf in glibc:
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48891
+// and the same for isnan and signbit.
+template <>
+class numeric_limits<fmt::internal::dummy_int> :
+    public std::numeric_limits<int> {
+ public:
+  // Portable version of isinf.
+  template <typename T>
+  static bool isinfinity(T x) {
+    using namespace fmt::internal;
+    // The resolution "priority" is:
+    // isinf macro > std::isinf > ::isinf > fmt::internal::isinf
+    if (const_check(sizeof(isinf(x)) != sizeof(dummy_int)))
+      return isinf(x) != 0;
+    return !_finite(static_cast<double>(x));
+  }
+
+  // Portable version of isnan.
+  template <typename T>
+  static bool isnotanumber(T x) {
+    using namespace fmt::internal;
+    if (const_check(sizeof(isnan(x)) != sizeof(fmt::internal::dummy_int)))
+      return isnan(x) != 0;
+    return _isnan(static_cast<double>(x)) != 0;
+  }
+
+  // Portable version of signbit.
+  static bool isnegative(double x) {
+    using namespace fmt::internal;
+    if (const_check(sizeof(signbit(x)) != sizeof(fmt::internal::dummy_int)))
+      return signbit(x) != 0;
+    if (x < 0) return true;
+    if (!isnotanumber(x)) return false;
+    int dec = 0, sign = 0;
+    char buffer[2];  // The buffer size must be >= 2 or _ecvt_s will fail.
+    _ecvt_s(buffer, sizeof(buffer), x, 0, &dec, &sign);
+    return sign != 0;
+  }
+};
+}  // namespace std
+
+FMT_BEGIN_NAMESPACE
+template <typename Range>
+class basic_writer;
+
+template <typename OutputIt, typename T = typename OutputIt::value_type>
+class output_range {
+ private:
+  OutputIt it_;
+
+  // Unused yet.
+  typedef void sentinel;
+  sentinel end() const;
+
+ public:
+  typedef OutputIt iterator;
+  typedef T value_type;
+
+  explicit output_range(OutputIt it): it_(it) {}
+  OutputIt begin() const { return it_; }
+};
+
+// A range where begin() returns back_insert_iterator.
+template <typename Container>
+class back_insert_range:
+    public output_range<std::back_insert_iterator<Container>> {
+  typedef output_range<std::back_insert_iterator<Container>> base;
+ public:
+  typedef typename Container::value_type value_type;
+
+  back_insert_range(Container &c): base(std::back_inserter(c)) {}
+  back_insert_range(typename base::iterator it): base(it) {}
+};
+
+typedef basic_writer<back_insert_range<internal::buffer>> writer;
+typedef basic_writer<back_insert_range<internal::wbuffer>> wwriter;
+
+/** A formatting error such as invalid format string. */
+class format_error : public std::runtime_error {
+ public:
+  explicit format_error(const char *message)
+  : std::runtime_error(message) {}
+
+  explicit format_error(const std::string &message)
+  : std::runtime_error(message) {}
+};
+
+namespace internal {
+
+#if FMT_SECURE_SCL
+template <typename T>
+struct checked { typedef stdext::checked_array_iterator<T*> type; };
+
+// Make a checked iterator to avoid warnings on MSVC.
+template <typename T>
+inline stdext::checked_array_iterator<T*> make_checked(T *p, std::size_t size) {
+  return {p, size};
+}
+#else
+template <typename T>
+struct checked { typedef T *type; };
+template <typename T>
+inline T *make_checked(T *p, std::size_t) { return p; }
+#endif
+
+template <typename T>
+template <typename U>
+void basic_buffer<T>::append(const U *begin, const U *end) {
+  std::size_t new_size = size_ + internal::to_unsigned(end - begin);
+  reserve(new_size);
+  std::uninitialized_copy(begin, end,
+                          internal::make_checked(ptr_, capacity_) + size_);
+  size_ = new_size;
+}
+}  // namespace internal
+
+// A wrapper around std::locale used to reduce compile times since <locale>
+// is very heavy.
+class locale;
+
+class locale_provider {
+ public:
+  virtual ~locale_provider() {}
+  virtual fmt::locale locale();
+};
+
+// The number of characters to store in the basic_memory_buffer object itself
+// to avoid dynamic memory allocation.
+enum { inline_buffer_size = 500 };
+
+/**
+  \rst
+  A dynamically growing memory buffer for trivially copyable/constructible types
+  with the first ``SIZE`` elements stored in the object itself.
+
+  You can use one of the following typedefs for common character types:
+
+  +----------------+------------------------------+
+  | Type           | Definition                   |
+  +================+==============================+
+  | memory_buffer  | basic_memory_buffer<char>    |
+  +----------------+------------------------------+
+  | wmemory_buffer | basic_memory_buffer<wchar_t> |
+  +----------------+------------------------------+
+
+  **Example**::
+
+     fmt::memory_buffer out;
+     format_to(out, "The answer is {}.", 42);
+
+  This will write the following output to the ``out`` object:
+
+  .. code-block:: none
+
+     The answer is 42.
+
+  The output can be converted to an ``std::string`` with ``to_string(out)``.
+  \endrst
+ */
+template <typename T, std::size_t SIZE = inline_buffer_size,
+          typename Allocator = std::allocator<T> >
+class basic_memory_buffer: private Allocator, public internal::basic_buffer<T> {
+ private:
+  T store_[SIZE];
+
+  // Deallocate memory allocated by the buffer.
+  void deallocate() {
+    T* data = this->data();
+    if (data != store_) Allocator::deallocate(data, this->capacity());
+  }
+
+ protected:
+  void grow(std::size_t size) FMT_OVERRIDE;
+
+ public:
+  explicit basic_memory_buffer(const Allocator &alloc = Allocator())
+      : Allocator(alloc) {
+    this->set(store_, SIZE);
+  }
+  ~basic_memory_buffer() { deallocate(); }
+
+ private:
+  // Move data from other to this buffer.
+  void move(basic_memory_buffer &other) {
+    Allocator &this_alloc = *this, &other_alloc = other;
+    this_alloc = std::move(other_alloc);
+    T* data = other.data();
+    std::size_t size = other.size(), capacity = other.capacity();
+    if (data == other.store_) {
+      this->set(store_, capacity);
+      std::uninitialized_copy(other.store_, other.store_ + size,
+                              internal::make_checked(store_, capacity));
+    } else {
+      this->set(data, capacity);
+      // Set pointer to the inline array so that delete is not called
+      // when deallocating.
+      other.set(other.store_, 0);
+    }
+    this->resize(size);
+  }
+
+ public:
+  /**
+    \rst
+    Constructs a :class:`fmt::basic_memory_buffer` object moving the content
+    of the other object to it.
+    \endrst
+   */
+  basic_memory_buffer(basic_memory_buffer &&other) {
+    move(other);
+  }
+
+  /**
+    \rst
+    Moves the content of the other ``basic_memory_buffer`` object to this one.
+    \endrst
+   */
+  basic_memory_buffer &operator=(basic_memory_buffer &&other) {
+    assert(this != &other);
+    deallocate();
+    move(other);
+    return *this;
+  }
+
+  // Returns a copy of the allocator associated with this buffer.
+  Allocator get_allocator() const { return *this; }
+};
+
+template <typename T, std::size_t SIZE, typename Allocator>
+void basic_memory_buffer<T, SIZE, Allocator>::grow(std::size_t size) {
+  std::size_t old_capacity = this->capacity();
+  std::size_t new_capacity = old_capacity + old_capacity / 2;
+  if (size > new_capacity)
+      new_capacity = size;
+  T *old_data = this->data();
+  T *new_data = internal::allocate<Allocator>(*this, new_capacity);
+  // The following code doesn't throw, so the raw pointer above doesn't leak.
+  std::uninitialized_copy(old_data, old_data + this->size(),
+                          internal::make_checked(new_data, new_capacity));
+  this->set(new_data, new_capacity);
+  // deallocate must not throw according to the standard, but even if it does,
+  // the buffer already uses the new storage and will deallocate it in
+  // destructor.
+  if (old_data != store_)
+    Allocator::deallocate(old_data, old_capacity);
+}
+
+typedef basic_memory_buffer<char> memory_buffer;
+typedef basic_memory_buffer<wchar_t> wmemory_buffer;
+
+/**
+  \rst
+  A fixed-size memory buffer. For a dynamically growing buffer use
+  :class:`fmt::basic_memory_buffer`.
+
+  Trying to increase the buffer size past the initial capacity will throw
+  ``std::runtime_error``.
+  \endrst
+ */
+template <typename Char>
+class basic_fixed_buffer : public internal::basic_buffer<Char> {
+ public:
+  /**
+   \rst
+   Constructs a :class:`fmt::basic_fixed_buffer` object for *array* of the
+   given size.
+   \endrst
+   */
+  basic_fixed_buffer(Char *array, std::size_t size) {
+    this->set(array, size);
+  }
+
+  /**
+   \rst
+   Constructs a :class:`fmt::basic_fixed_buffer` object for *array* of the
+   size known at compile time.
+   \endrst
+   */
+  template <std::size_t SIZE>
+  explicit basic_fixed_buffer(Char (&array)[SIZE]) {
+    this->set(array, SIZE);
+  }
+
+ protected:
+  FMT_API void grow(std::size_t size) FMT_OVERRIDE;
+};
+
+namespace internal {
+
+template <typename Char>
+struct char_traits;
+
+template <>
+struct char_traits<char> {
+  // Formats a floating-point number.
+  template <typename T>
+  FMT_API static int format_float(char *buffer, std::size_t size,
+      const char *format, int precision, T value);
+};
+
+template <>
+struct char_traits<wchar_t> {
+  template <typename T>
+  FMT_API static int format_float(wchar_t *buffer, std::size_t size,
+      const wchar_t *format, int precision, T value);
+};
+
+#if FMT_USE_EXTERN_TEMPLATES
+extern template int char_traits<char>::format_float<double>(
+    char *buffer, std::size_t size, const char* format, int precision,
+    double value);
+extern template int char_traits<char>::format_float<long double>(
+    char *buffer, std::size_t size, const char* format, int precision,
+    long double value);
+
+extern template int char_traits<wchar_t>::format_float<double>(
+    wchar_t *buffer, std::size_t size, const wchar_t* format, int precision,
+    double value);
+extern template int char_traits<wchar_t>::format_float<long double>(
+    wchar_t *buffer, std::size_t size, const wchar_t* format, int precision,
+    long double value);
+#endif
+
+template <typename Container>
+inline typename std::enable_if<
+  is_contiguous<Container>::value,
+  typename checked<typename Container::value_type>::type>::type
+    reserve(std::back_insert_iterator<Container> &it, std::size_t n) {
+  Container &c = internal::get_container(it);
+  std::size_t size = c.size();
+  c.resize(size + n);
+  return make_checked(&c[size], n);
+}
+
+template <typename Iterator>
+inline Iterator &reserve(Iterator &it, std::size_t) { return it; }
+
+template <typename Char>
+class null_terminating_iterator;
+
+template <typename Char>
+FMT_CONSTEXPR_DECL const Char *pointer_from(null_terminating_iterator<Char> it);
+
+// An iterator that produces a null terminator on *end. This simplifies parsing
+// and allows comparing the performance of processing a null-terminated string
+// vs string_view.
+template <typename Char>
+class null_terminating_iterator {
+ public:
+  typedef std::ptrdiff_t difference_type;
+  typedef Char value_type;
+  typedef const Char* pointer;
+  typedef const Char& reference;
+  typedef std::random_access_iterator_tag iterator_category;
+
+  null_terminating_iterator() : ptr_(0), end_(0) {}
+
+  FMT_CONSTEXPR null_terminating_iterator(const Char *ptr, const Char *end)
+    : ptr_(ptr), end_(end) {}
+
+  template <typename Range>
+  FMT_CONSTEXPR explicit null_terminating_iterator(const Range &r)
+    : ptr_(r.begin()), end_(r.end()) {}
+
+  null_terminating_iterator &operator=(const Char *ptr) {
+    assert(ptr <= end_);
+    ptr_ = ptr;
+    return *this;
+  }
+
+  FMT_CONSTEXPR Char operator*() const {
+    return ptr_ != end_ ? *ptr_ : 0;
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator++() {
+    ++ptr_;
+    return *this;
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator++(int) {
+    null_terminating_iterator result(*this);
+    ++ptr_;
+    return result;
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator--() {
+    --ptr_;
+    return *this;
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator+(difference_type n) {
+    return null_terminating_iterator(ptr_ + n, end_);
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator-(difference_type n) {
+    return null_terminating_iterator(ptr_ - n, end_);
+  }
+
+  FMT_CONSTEXPR null_terminating_iterator operator+=(difference_type n) {
+    ptr_ += n;
+    return *this;
+  }
+
+  FMT_CONSTEXPR difference_type operator-(
+      null_terminating_iterator other) const {
+    return ptr_ - other.ptr_;
+  }
+
+  FMT_CONSTEXPR bool operator!=(null_terminating_iterator other) const {
+    return ptr_ != other.ptr_;
+  }
+
+  bool operator>=(null_terminating_iterator other) const {
+    return ptr_ >= other.ptr_;
+  }
+
+  // This should be a friend specialization pointer_from<Char> but the latter
+  // doesn't compile by gcc 5.1 due to a compiler bug.
+  template <typename CharT>
+  friend FMT_CONSTEXPR_DECL const CharT *pointer_from(
+      null_terminating_iterator<CharT> it);
+
+ private:
+  const Char *ptr_;
+  const Char *end_;
+};
+
+template <typename T>
+FMT_CONSTEXPR const T *pointer_from(const T *p) { return p; }
+
+template <typename Char>
+FMT_CONSTEXPR const Char *pointer_from(null_terminating_iterator<Char> it) {
+  return it.ptr_;
+}
+
+// An output iterator that counts the number of objects written to it and
+// discards them.
+template <typename T>
+class counting_iterator {
+ private:
+  std::size_t count_;
+  mutable T blackhole_;
+
+ public:
+  typedef std::output_iterator_tag iterator_category;
+  typedef T value_type;
+  typedef std::ptrdiff_t difference_type;
+  typedef T* pointer;
+  typedef T& reference;
+  typedef counting_iterator _Unchecked_type;  // Mark iterator as checked.
+
+  counting_iterator(): count_(0) {}
+
+  std::size_t count() const { return count_; }
+
+  counting_iterator& operator++() {
+    ++count_;
+    return *this;
+  }
+
+  counting_iterator operator++(int) {
+    auto it = *this;
+    ++*this;
+    return it;
+  }
+
+  T &operator*() const { return blackhole_; }
+};
+
+// An output iterator that truncates the output and counts the number of objects
+// written to it.
+template <typename OutputIt>
+class truncating_iterator {
+ private:
+  typedef std::iterator_traits<OutputIt> traits;
+
+  OutputIt out_;
+  std::size_t limit_;
+  std::size_t count_;
+  mutable typename traits::value_type blackhole_;
+
+ public:
+  typedef std::output_iterator_tag iterator_category;
+  typedef typename traits::value_type value_type;
+  typedef typename traits::difference_type difference_type;
+  typedef typename traits::pointer pointer;
+  typedef typename traits::reference reference;
+  typedef truncating_iterator _Unchecked_type;  // Mark iterator as checked.
+
+  truncating_iterator(OutputIt out, std::size_t limit)
+    : out_(out), limit_(limit), count_(0) {}
+
+  OutputIt base() const { return out_; }
+  std::size_t count() const { return count_; }
+
+  truncating_iterator& operator++() {
+    if (count_++ < limit_)
+      ++out_;
+    return *this;
+  }
+
+  truncating_iterator operator++(int) {
+    auto it = *this;
+    ++*this;
+    return it;
+  }
+
+  reference operator*() const { return count_ < limit_ ? *out_ : blackhole_; }
+};
+
+// Returns true if value is negative, false otherwise.
+// Same as (value < 0) but doesn't produce warnings if T is an unsigned type.
+template <typename T>
+FMT_CONSTEXPR typename std::enable_if<
+    std::numeric_limits<T>::is_signed, bool>::type is_negative(T value) {
+  return value < 0;
+}
+template <typename T>
+FMT_CONSTEXPR typename std::enable_if<
+    !std::numeric_limits<T>::is_signed, bool>::type is_negative(T) {
+  return false;
+}
+
+template <typename T>
+struct int_traits {
+  // Smallest of uint32_t and uint64_t that is large enough to represent
+  // all values of T.
+  typedef typename std::conditional<
+    std::numeric_limits<T>::digits <= 32, uint32_t, uint64_t>::type main_type;
+};
+
+// Static data is placed in this class template to allow header-only
+// configuration.
+template <typename T = void>
+struct FMT_API basic_data {
+  static const uint32_t POWERS_OF_10_32[];
+  static const uint64_t POWERS_OF_10_64[];
+  static const uint64_t POW10_SIGNIFICANDS[];
+  static const int16_t POW10_EXPONENTS[];
+  static const char DIGITS[];
+  static const char RESET_COLOR[];
+  static const wchar_t WRESET_COLOR[];
+};
+
+#if FMT_USE_EXTERN_TEMPLATES
+extern template struct basic_data<void>;
+#endif
+
+typedef basic_data<> data;
+
+#ifdef FMT_BUILTIN_CLZLL
+// Returns the number of decimal digits in n. Leading zeros are not counted
+// except for n == 0 in which case count_digits returns 1.
+inline unsigned count_digits(uint64_t n) {
+  // Based on http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+  // and the benchmark https://github.com/localvoid/cxx-benchmark-count-digits.
+  int t = (64 - FMT_BUILTIN_CLZLL(n | 1)) * 1233 >> 12;
+  return to_unsigned(t) - (n < data::POWERS_OF_10_64[t]) + 1;
+}
+#else
+// Fallback version of count_digits used when __builtin_clz is not available.
+inline unsigned count_digits(uint64_t n) {
+  unsigned count = 1;
+  for (;;) {
+    // Integer division is slow so do it for a group of four digits instead
+    // of for every digit. The idea comes from the talk by Alexandrescu
+    // "Three Optimization Tips for C++". See speed-test for a comparison.
+    if (n < 10) return count;
+    if (n < 100) return count + 1;
+    if (n < 1000) return count + 2;
+    if (n < 10000) return count + 3;
+    n /= 10000u;
+    count += 4;
+  }
+}
+#endif
+
+#if FMT_HAS_CPP_ATTRIBUTE(always_inline)
+# define FMT_ALWAYS_INLINE __attribute__((always_inline))
+#else
+# define FMT_ALWAYS_INLINE
+#endif
+
+template <typename Handler>
+inline char *lg(uint32_t n, Handler h) FMT_ALWAYS_INLINE;
+
+// Computes g = floor(log10(n)) and calls h.on<g>(n);
+template <typename Handler>
+inline char *lg(uint32_t n, Handler h) {
+  return n < 100 ? n < 10 ? h.template on<0>(n) : h.template on<1>(n)
+                 : n < 1000000
+                       ? n < 10000 ? n < 1000 ? h.template on<2>(n)
+                                              : h.template on<3>(n)
+                                   : n < 100000 ? h.template on<4>(n)
+                                                : h.template on<5>(n)
+                       : n < 100000000 ? n < 10000000 ? h.template on<6>(n)
+                                                      : h.template on<7>(n)
+                                       : n < 1000000000 ? h.template on<8>(n)
+                                                        : h.template on<9>(n);
+}
+
+// An lg handler that formats a decimal number.
+// Usage: lg(n, decimal_formatter(buffer));
+class decimal_formatter {
+ private:
+  char *buffer_;
+
+  void write_pair(unsigned N, uint32_t index) {
+    std::memcpy(buffer_ + N, data::DIGITS + index * 2, 2);
+  }
+
+ public:
+  explicit decimal_formatter(char *buf) : buffer_(buf) {}
+
+  template <unsigned N> char *on(uint32_t u) {
+    if (N == 0) {
+      *buffer_ = static_cast<char>(u) + '0';
+    } else if (N == 1) {
+      write_pair(0, u);
+    } else {
+      // The idea of using 4.32 fixed-point numbers is based on
+      // https://github.com/jeaiii/itoa
+      unsigned n = N - 1;
+      unsigned a = n / 5 * n * 53 / 16;
+      uint64_t t = ((1ULL << (32 + a)) / data::POWERS_OF_10_32[n] + 1 - n / 9);
+      t = ((t * u) >> a) + n / 5 * 4;
+      write_pair(0, t >> 32);
+      for (unsigned i = 2; i < N; i += 2) {
+        t = 100ULL * static_cast<uint32_t>(t);
+        write_pair(i, t >> 32);
+      }
+      if (N % 2 == 0) {
+        buffer_[N] = static_cast<char>(
+          (10ULL * static_cast<uint32_t>(t)) >> 32) + '0';
+      }
+    }
+    return buffer_ += N + 1;
+  }
+};
+
+// An lg handler that formats a decimal number with a terminating null.
+class decimal_formatter_null : public decimal_formatter {
+ public:
+  explicit decimal_formatter_null(char *buf) : decimal_formatter(buf) {}
+
+  template <unsigned N> char *on(uint32_t u) {
+    char *buf = decimal_formatter::on<N>(u);
+    *buf = '\0';
+    return buf;
+  }
+};
+
+#ifdef FMT_BUILTIN_CLZ
+// Optional version of count_digits for better performance on 32-bit platforms.
+inline unsigned count_digits(uint32_t n) {
+  int t = (32 - FMT_BUILTIN_CLZ(n | 1)) * 1233 >> 12;
+  return to_unsigned(t) - (n < data::POWERS_OF_10_32[t]) + 1;
+}
+#endif
+
+// A functor that doesn't add a thousands separator.
+struct no_thousands_sep {
+  typedef char char_type;
+
+  template <typename Char>
+  void operator()(Char *) {}
+};
+
+// A functor that adds a thousands separator.
+template <typename Char>
+class add_thousands_sep {
+ private:
+  basic_string_view<Char> sep_;
+
+  // Index of a decimal digit with the least significant digit having index 0.
+  unsigned digit_index_;
+
+ public:
+  typedef Char char_type;
+
+  explicit add_thousands_sep(basic_string_view<Char> sep)
+    : sep_(sep), digit_index_(0) {}
+
+  void operator()(Char *&buffer) {
+    if (++digit_index_ % 3 != 0)
+      return;
+    buffer -= sep_.size();
+    std::uninitialized_copy(sep_.data(), sep_.data() + sep_.size(),
+                            internal::make_checked(buffer, sep_.size()));
+  }
+};
+
+template <typename Char>
+FMT_API Char thousands_sep(locale_provider *lp);
+
+// Formats a decimal unsigned integer value writing into buffer.
+// thousands_sep is a functor that is called after writing each char to
+// add a thousands separator if necessary.
+template <typename UInt, typename Char, typename ThousandsSep>
+inline Char *format_decimal(Char *buffer, UInt value, unsigned num_digits,
+                            ThousandsSep thousands_sep) {
+  buffer += num_digits;
+  Char *end = buffer;
+  while (value >= 100) {
+    // Integer division is slow so do it for a group of two digits instead
+    // of for every digit. The idea comes from the talk by Alexandrescu
+    // "Three Optimization Tips for C++". See speed-test for a comparison.
+    unsigned index = static_cast<unsigned>((value % 100) * 2);
+    value /= 100;
+    *--buffer = data::DIGITS[index + 1];
+    thousands_sep(buffer);
+    *--buffer = data::DIGITS[index];
+    thousands_sep(buffer);
+  }
+  if (value < 10) {
+    *--buffer = static_cast<char>('0' + value);
+    return end;
+  }
+  unsigned index = static_cast<unsigned>(value * 2);
+  *--buffer = data::DIGITS[index + 1];
+  thousands_sep(buffer);
+  *--buffer = data::DIGITS[index];
+  return end;
+}
+
+template <typename UInt, typename Iterator, typename ThousandsSep>
+inline Iterator format_decimal(
+    Iterator out, UInt value, unsigned num_digits, ThousandsSep sep) {
+  typedef typename ThousandsSep::char_type char_type;
+  // Buffer should be large enough to hold all digits (digits10 + 1) and null.
+  char_type buffer[std::numeric_limits<UInt>::digits10 + 2];
+  format_decimal(buffer, value, num_digits, sep);
+  return std::copy_n(buffer, num_digits, out);
+}
+
+template <typename It, typename UInt>
+inline It format_decimal(It out, UInt value, unsigned num_digits) {
+  return format_decimal(out, value, num_digits, no_thousands_sep());
+}
+
+template <unsigned BASE_BITS, typename Char, typename UInt>
+inline Char *format_uint(Char *buffer, UInt value, unsigned num_digits,
+                         bool upper = false) {
+  buffer += num_digits;
+  Char *end = buffer;
+  do {
+    const char *digits = upper ? "0123456789ABCDEF" : "0123456789abcdef";
+    unsigned digit = (value & ((1 << BASE_BITS) - 1));
+    *--buffer = BASE_BITS < 4 ? static_cast<char>('0' + digit) : digits[digit];
+  } while ((value >>= BASE_BITS) != 0);
+  return end;
+}
+
+template <unsigned BASE_BITS, typename It, typename UInt>
+inline It format_uint(It out, UInt value, unsigned num_digits,
+                      bool upper = false) {
+  // Buffer should be large enough to hold all digits (digits / BASE_BITS + 1)
+  // and null.
+  char buffer[std::numeric_limits<UInt>::digits / BASE_BITS + 2];
+  format_uint<BASE_BITS>(buffer, value, num_digits, upper);
+  return std::copy_n(buffer, num_digits, out);
+}
+
+#ifndef _WIN32
+# define FMT_USE_WINDOWS_H 0
+#elif !defined(FMT_USE_WINDOWS_H)
+# define FMT_USE_WINDOWS_H 1
+#endif
+
+// Define FMT_USE_WINDOWS_H to 0 to disable use of windows.h.
+// All the functionality that relies on it will be disabled too.
+#if FMT_USE_WINDOWS_H
+// A converter from UTF-8 to UTF-16.
+// It is only provided for Windows since other systems support UTF-8 natively.
+class utf8_to_utf16 {
+ private:
+  wmemory_buffer buffer_;
+
+ public:
+  FMT_API explicit utf8_to_utf16(string_view s);
+  operator wstring_view() const { return wstring_view(&buffer_[0], size()); }
+  size_t size() const { return buffer_.size() - 1; }
+  const wchar_t *c_str() const { return &buffer_[0]; }
+  std::wstring str() const { return std::wstring(&buffer_[0], size()); }
+};
+
+// A converter from UTF-16 to UTF-8.
+// It is only provided for Windows since other systems support UTF-8 natively.
+class utf16_to_utf8 {
+ private:
+  memory_buffer buffer_;
+
+ public:
+  utf16_to_utf8() {}
+  FMT_API explicit utf16_to_utf8(wstring_view s);
+  operator string_view() const { return string_view(&buffer_[0], size()); }
+  size_t size() const { return buffer_.size() - 1; }
+  const char *c_str() const { return &buffer_[0]; }
+  std::string str() const { return std::string(&buffer_[0], size()); }
+
+  // Performs conversion returning a system error code instead of
+  // throwing exception on conversion error. This method may still throw
+  // in case of memory allocation error.
+  FMT_API int convert(wstring_view s);
+};
+
+FMT_API void format_windows_error(fmt::internal::buffer &out, int error_code,
+                                  fmt::string_view message) FMT_NOEXCEPT;
+#endif
+
+template <typename T = void>
+struct null {};
+}  // namespace internal
+
+struct monostate {};
+
+/**
+  \rst
+  Visits an argument dispatching to the appropriate visit method based on
+  the argument type. For example, if the argument type is ``double`` then
+  ``vis(value)`` will be called with the value of type ``double``.
+  \endrst
+ */
+template <typename Visitor, typename Context>
+FMT_CONSTEXPR typename internal::result_of<Visitor(int)>::type
+    visit(Visitor &&vis, basic_format_arg<Context> arg) {
+  typedef typename Context::char_type char_type;
+  switch (arg.type_) {
+  case internal::none_type:
+    break;
+  case internal::named_arg_type:
+    FMT_ASSERT(false, "invalid argument type");
+    break;
+  case internal::int_type:
+    return vis(arg.value_.int_value);
+  case internal::uint_type:
+    return vis(arg.value_.uint_value);
+  case internal::long_long_type:
+    return vis(arg.value_.long_long_value);
+  case internal::ulong_long_type:
+    return vis(arg.value_.ulong_long_value);
+  case internal::bool_type:
+    return vis(arg.value_.int_value != 0);
+  case internal::char_type:
+    return vis(static_cast<char_type>(arg.value_.int_value));
+  case internal::double_type:
+    return vis(arg.value_.double_value);
+  case internal::long_double_type:
+    return vis(arg.value_.long_double_value);
+  case internal::cstring_type:
+    return vis(arg.value_.string.value);
+  case internal::string_type:
+    return vis(basic_string_view<char_type>(
+                 arg.value_.string.value, arg.value_.string.size));
+  case internal::pointer_type:
+    return vis(arg.value_.pointer);
+  case internal::custom_type:
+    return vis(typename basic_format_arg<Context>::handle(arg.value_.custom));
+  }
+  return vis(monostate());
+}
+
+enum alignment {
+  ALIGN_DEFAULT, ALIGN_LEFT, ALIGN_RIGHT, ALIGN_CENTER, ALIGN_NUMERIC
+};
+
+// Flags.
+enum {SIGN_FLAG = 1, PLUS_FLAG = 2, MINUS_FLAG = 4, HASH_FLAG = 8};
+
+enum format_spec_tag {fill_tag, align_tag, width_tag, type_tag};
+
+// Format specifier.
+template <typename T, format_spec_tag>
+class format_spec {
+ private:
+  T value_;
+
+ public:
+  typedef T value_type;
+
+  explicit format_spec(T value) : value_(value) {}
+
+  T value() const { return value_; }
+};
+
+// template <typename Char>
+// typedef format_spec<Char, fill_tag> fill_spec;
+template <typename Char>
+class fill_spec : public format_spec<Char, fill_tag> {
+ public:
+  explicit fill_spec(Char value) : format_spec<Char, fill_tag>(value) {}
+};
+
+typedef format_spec<unsigned, width_tag> width_spec;
+typedef format_spec<char, type_tag> type_spec;
+
+// An empty format specifier.
+struct empty_spec {};
+
+// An alignment specifier.
+struct align_spec : empty_spec {
+  unsigned width_;
+  // Fill is always wchar_t and cast to char if necessary to avoid having
+  // two specialization of AlignSpec and its subclasses.
+  wchar_t fill_;
+  alignment align_;
+
+  FMT_CONSTEXPR align_spec(
+      unsigned width, wchar_t fill, alignment align = ALIGN_DEFAULT)
+  : width_(width), fill_(fill), align_(align) {}
+
+  FMT_CONSTEXPR unsigned width() const { return width_; }
+  FMT_CONSTEXPR wchar_t fill() const { return fill_; }
+  FMT_CONSTEXPR alignment align() const { return align_; }
+
+  int precision() const { return -1; }
+};
+
+// Format specifiers.
+template <typename Char>
+class basic_format_specs : public align_spec {
+ public:
+  unsigned flags_;
+  int precision_;
+  Char type_;
+
+  FMT_CONSTEXPR basic_format_specs(
+      unsigned width = 0, char type = 0, wchar_t fill = ' ')
+  : align_spec(width, fill), flags_(0), precision_(-1), type_(type) {}
+
+  FMT_CONSTEXPR bool flag(unsigned f) const { return (flags_ & f) != 0; }
+  FMT_CONSTEXPR int precision() const { return precision_; }
+  FMT_CONSTEXPR Char type() const { return type_; }
+};
+
+typedef basic_format_specs<char> format_specs;
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR unsigned basic_parse_context<Char, ErrorHandler>::next_arg_id() {
+  if (next_arg_id_ >= 0)
+    return internal::to_unsigned(next_arg_id_++);
+  on_error("cannot switch from manual to automatic argument indexing");
+  return 0;
+}
+
+struct format_string {};
+
+namespace internal {
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_int_type_spec(Char spec, Handler &&handler) {
+  switch (spec) {
+  case 0: case 'd':
+    handler.on_dec();
+    break;
+  case 'x': case 'X':
+    handler.on_hex();
+    break;
+  case 'b': case 'B':
+    handler.on_bin();
+    break;
+  case 'o':
+    handler.on_oct();
+    break;
+  case 'n':
+    handler.on_num();
+    break;
+  default:
+    handler.on_error();
+  }
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_float_type_spec(Char spec, Handler &&handler) {
+  switch (spec) {
+  case 0: case 'g': case 'G':
+    handler.on_general();
+    break;
+  case 'e': case 'E':
+    handler.on_exp();
+    break;
+  case 'f': case 'F':
+    handler.on_fixed();
+    break;
+   case 'a': case 'A':
+    handler.on_hex();
+    break;
+  default:
+    handler.on_error();
+    break;
+  }
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_char_specs(
+    const basic_format_specs<Char> &specs, Handler &&handler) {
+  if (specs.type() && specs.type() != 'c') {
+    handler.on_int();
+    return;
+  }
+  if (specs.align() == ALIGN_NUMERIC || specs.flag(~0u) != 0)
+    handler.on_error("invalid format specifier for char");
+  handler.on_char();
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_cstring_type_spec(Char spec, Handler &&handler) {
+  if (spec == 0 || spec == 's')
+    handler.on_string();
+  else if (spec == 'p')
+    handler.on_pointer();
+  else
+    handler.on_error("invalid type specifier");
+}
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void check_string_type_spec(Char spec, ErrorHandler &&eh) {
+  if (spec != 0 && spec != 's')
+    eh.on_error("invalid type specifier");
+}
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void check_pointer_type_spec(Char spec, ErrorHandler &&eh) {
+  if (spec != 0 && spec != 'p')
+    eh.on_error("invalid type specifier");
+}
+
+template <typename ErrorHandler>
+class int_type_checker : private ErrorHandler {
+ public:
+  FMT_CONSTEXPR explicit int_type_checker(ErrorHandler eh) : ErrorHandler(eh) {}
+
+  FMT_CONSTEXPR void on_dec() {}
+  FMT_CONSTEXPR void on_hex() {}
+  FMT_CONSTEXPR void on_bin() {}
+  FMT_CONSTEXPR void on_oct() {}
+  FMT_CONSTEXPR void on_num() {}
+
+  FMT_CONSTEXPR void on_error() {
+    ErrorHandler::on_error("invalid type specifier");
+  }
+};
+
+template <typename ErrorHandler>
+class float_type_checker : private ErrorHandler {
+ public:
+  FMT_CONSTEXPR explicit float_type_checker(ErrorHandler eh)
+    : ErrorHandler(eh) {}
+
+  FMT_CONSTEXPR void on_general() {}
+  FMT_CONSTEXPR void on_exp() {}
+  FMT_CONSTEXPR void on_fixed() {}
+  FMT_CONSTEXPR void on_hex() {}
+
+  FMT_CONSTEXPR void on_error() {
+    ErrorHandler::on_error("invalid type specifier");
+  }
+};
+
+template <typename ErrorHandler, typename CharType>
+class char_specs_checker : public ErrorHandler {
+ private:
+  CharType type_;
+
+ public:
+  FMT_CONSTEXPR char_specs_checker(CharType type, ErrorHandler eh)
+    : ErrorHandler(eh), type_(type) {}
+
+  FMT_CONSTEXPR void on_int() {
+    handle_int_type_spec(type_, int_type_checker<ErrorHandler>(*this));
+  }
+  FMT_CONSTEXPR void on_char() {}
+};
+
+template <typename ErrorHandler>
+class cstring_type_checker : public ErrorHandler {
+ public:
+  FMT_CONSTEXPR explicit cstring_type_checker(ErrorHandler eh)
+    : ErrorHandler(eh) {}
+
+  FMT_CONSTEXPR void on_string() {}
+  FMT_CONSTEXPR void on_pointer() {}
+};
+
+template <typename Context>
+void arg_map<Context>::init(const basic_format_args<Context> &args) {
+  if (map_)
+    return;
+  map_ = new entry[args.max_size()];
+  bool use_values = args.type(max_packed_args - 1) == internal::none_type;
+  if (use_values) {
+    for (unsigned i = 0;/*nothing*/; ++i) {
+      internal::type arg_type = args.type(i);
+      switch (arg_type) {
+        case internal::none_type:
+          return;
+        case internal::named_arg_type:
+          push_back(args.values_[i]);
+          break;
+        default:
+          break; // Do nothing.
+      }
+    }
+    return;
+  }
+  for (unsigned i = 0; ; ++i) {
+    switch (args.args_[i].type_) {
+      case internal::none_type:
+        return;
+      case internal::named_arg_type:
+        push_back(args.args_[i].value_);
+        break;
+      default:
+        break; // Do nothing.
+    }
+  }
+}
+
+template <typename Range>
+class arg_formatter_base {
+ public:
+  typedef typename Range::value_type char_type;
+  typedef decltype(internal::declval<Range>().begin()) iterator;
+  typedef basic_format_specs<char_type> format_specs;
+
+ private:
+  typedef basic_writer<Range> writer_type;
+  writer_type writer_;
+  format_specs &specs_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(arg_formatter_base);
+
+  struct char_writer {
+    char_type value;
+    template <typename It>
+    void operator()(It &&it) const { *it++ = value; }
+  };
+
+  void write_char(char_type value) {
+    writer_.write_padded(1, specs_, char_writer{value});
+  }
+
+  void write_pointer(const void *p) {
+    format_specs specs = specs_;
+    specs.flags_ = HASH_FLAG;
+    specs.type_ = 'x';
+    writer_.write_int(reinterpret_cast<uintptr_t>(p), specs);
+  }
+
+ protected:
+  writer_type &writer() { return writer_; }
+  format_specs &spec() { return specs_; }
+  iterator out() { return writer_.out(); }
+
+  void write(bool value) {
+    writer_.write_str(string_view(value ? "true" : "false"), specs_);
+  }
+
+  void write(const char_type *value) {
+    if (!value)
+      FMT_THROW(format_error("string pointer is null"));
+    auto length = std::char_traits<char_type>::length(value);
+    writer_.write_str(basic_string_view<char_type>(value, length), specs_);
+  }
+
+ public:
+  arg_formatter_base(Range r, format_specs &s): writer_(r), specs_(s) {}
+
+  iterator operator()(monostate) {
+    FMT_ASSERT(false, "invalid argument type");
+    return out();
+  }
+
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value, iterator>::type
+      operator()(T value) {
+    // MSVC2013 fails to compile separate overloads for bool and char_type so
+    // use std::is_same instead.
+    if (std::is_same<T, bool>::value) {
+      if (specs_.type_)
+        return (*this)(value ? 1 : 0);
+      write(value != 0);
+    } else if (std::is_same<T, char_type>::value) {
+      internal::handle_char_specs(
+        specs_, char_spec_handler(*this, static_cast<char_type>(value)));
+    } else {
+      writer_.write_int(value, specs_);
+    }
+    return out();
+  }
+
+  template <typename T>
+  typename std::enable_if<std::is_floating_point<T>::value, iterator>::type
+      operator()(T value) {
+    writer_.write_double(value, specs_);
+    return out();
+  }
+
+  struct char_spec_handler : internal::error_handler {
+    arg_formatter_base &formatter;
+    char_type value;
+
+    char_spec_handler(arg_formatter_base& f, char_type val)
+      : formatter(f), value(val) {}
+
+    void on_int() { formatter.writer_.write_int(value, formatter.specs_); }
+    void on_char() { formatter.write_char(value); }
+  };
+
+  struct cstring_spec_handler : internal::error_handler {
+    arg_formatter_base &formatter;
+    const char_type *value;
+
+    cstring_spec_handler(arg_formatter_base &f, const char_type *val)
+      : formatter(f), value(val) {}
+
+    void on_string() { formatter.write(value); }
+    void on_pointer() { formatter.write_pointer(value); }
+  };
+
+  iterator operator()(const char_type *value) {
+    internal::handle_cstring_type_spec(
+          specs_.type_, cstring_spec_handler(*this, value));
+    return out();
+  }
+
+  iterator operator()(basic_string_view<char_type> value) {
+    internal::check_string_type_spec(specs_.type_, internal::error_handler());
+    writer_.write_str(value, specs_);
+    return out();
+  }
+
+  iterator operator()(const void *value) {
+    check_pointer_type_spec(specs_.type_, internal::error_handler());
+    write_pointer(value);
+    return out();
+  }
+};
+
+template <typename S>
+struct is_format_string:
+  std::integral_constant<bool, std::is_base_of<format_string, S>::value> {};
+
+template <typename Char>
+FMT_CONSTEXPR bool is_name_start(Char c) {
+  return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || '_' == c;
+}
+
+// Parses the input as an unsigned integer. This function assumes that the
+// first character is a digit and presence of a non-digit character at the end.
+// it: an iterator pointing to the beginning of the input range.
+template <typename Iterator, typename ErrorHandler>
+FMT_CONSTEXPR unsigned parse_nonnegative_int(Iterator &it, ErrorHandler &&eh) {
+  assert('0' <= *it && *it <= '9');
+  unsigned value = 0;
+  // Convert to unsigned to prevent a warning.
+  unsigned max_int = (std::numeric_limits<int>::max)();
+  unsigned big = max_int / 10;
+  do {
+    // Check for overflow.
+    if (value > big) {
+      value = max_int + 1;
+      break;
+    }
+    value = value * 10 + unsigned(*it - '0');
+    // Workaround for MSVC "setup_exception stack overflow" error:
+    auto next = it;
+    ++next;
+    it = next;
+  } while ('0' <= *it && *it <= '9');
+  if (value > max_int)
+    eh.on_error("number is too big");
+  return value;
+}
+
+template <typename Char, typename Context>
+class custom_formatter: public function<bool> {
+ private:
+  Context &ctx_;
+
+ public:
+  explicit custom_formatter(Context &ctx): ctx_(ctx) {}
+
+  bool operator()(typename basic_format_arg<Context>::handle h) const {
+    h.format(ctx_);
+    return true;
+  }
+
+  template <typename T>
+  bool operator()(T) const { return false; }
+};
+
+template <typename T>
+struct is_integer {
+  enum {
+    value = std::is_integral<T>::value && !std::is_same<T, bool>::value &&
+            !std::is_same<T, char>::value && !std::is_same<T, wchar_t>::value
+  };
+};
+
+template <typename ErrorHandler>
+class width_checker: public function<unsigned long long> {
+ public:
+  explicit FMT_CONSTEXPR width_checker(ErrorHandler &eh) : handler_(eh) {}
+
+  template <typename T>
+  FMT_CONSTEXPR
+  typename std::enable_if<
+      is_integer<T>::value, unsigned long long>::type operator()(T value) {
+    if (is_negative(value))
+      handler_.on_error("negative width");
+    return static_cast<unsigned long long>(value);
+  }
+
+  template <typename T>
+  FMT_CONSTEXPR typename std::enable_if<
+      !is_integer<T>::value, unsigned long long>::type operator()(T) {
+    handler_.on_error("width is not integer");
+    return 0;
+  }
+
+ private:
+  ErrorHandler &handler_;
+};
+
+template <typename ErrorHandler>
+class precision_checker: public function<unsigned long long> {
+ public:
+  explicit FMT_CONSTEXPR precision_checker(ErrorHandler &eh) : handler_(eh) {}
+
+  template <typename T>
+  FMT_CONSTEXPR typename std::enable_if<
+      is_integer<T>::value, unsigned long long>::type operator()(T value) {
+    if (is_negative(value))
+      handler_.on_error("negative precision");
+    return static_cast<unsigned long long>(value);
+  }
+
+  template <typename T>
+  FMT_CONSTEXPR typename std::enable_if<
+      !is_integer<T>::value, unsigned long long>::type operator()(T) {
+    handler_.on_error("precision is not integer");
+    return 0;
+  }
+
+ private:
+  ErrorHandler &handler_;
+};
+
+// A format specifier handler that sets fields in basic_format_specs.
+template <typename Char>
+class specs_setter {
+ public:
+  explicit FMT_CONSTEXPR specs_setter(basic_format_specs<Char> &specs):
+    specs_(specs) {}
+
+  FMT_CONSTEXPR specs_setter(const specs_setter &other) : specs_(other.specs_) {}
+
+  FMT_CONSTEXPR void on_align(alignment align) { specs_.align_ = align; }
+  FMT_CONSTEXPR void on_fill(Char fill) { specs_.fill_ = fill; }
+  FMT_CONSTEXPR void on_plus() { specs_.flags_ |= SIGN_FLAG | PLUS_FLAG; }
+  FMT_CONSTEXPR void on_minus() { specs_.flags_ |= MINUS_FLAG; }
+  FMT_CONSTEXPR void on_space() { specs_.flags_ |= SIGN_FLAG; }
+  FMT_CONSTEXPR void on_hash() { specs_.flags_ |= HASH_FLAG; }
+
+  FMT_CONSTEXPR void on_zero() {
+    specs_.align_ = ALIGN_NUMERIC;
+    specs_.fill_ = '0';
+  }
+
+  FMT_CONSTEXPR void on_width(unsigned width) { specs_.width_ = width; }
+  FMT_CONSTEXPR void on_precision(unsigned precision) {
+    specs_.precision_ = static_cast<int>(precision);
+  }
+  FMT_CONSTEXPR void end_precision() {}
+
+  FMT_CONSTEXPR void on_type(Char type) { specs_.type_ = type; }
+
+ protected:
+  basic_format_specs<Char> &specs_;
+};
+
+// A format specifier handler that checks if specifiers are consistent with the
+// argument type.
+template <typename Handler>
+class specs_checker : public Handler {
+ public:
+  FMT_CONSTEXPR specs_checker(const Handler& handler, internal::type arg_type)
+    : Handler(handler), arg_type_(arg_type) {}
+
+  FMT_CONSTEXPR specs_checker(const specs_checker &other)
+    : Handler(other), arg_type_(other.arg_type_) {}
+
+  FMT_CONSTEXPR void on_align(alignment align) {
+    if (align == ALIGN_NUMERIC)
+      require_numeric_argument();
+    Handler::on_align(align);
+  }
+
+  FMT_CONSTEXPR void on_plus() {
+    check_sign();
+    Handler::on_plus();
+  }
+
+  FMT_CONSTEXPR void on_minus() {
+    check_sign();
+    Handler::on_minus();
+  }
+
+  FMT_CONSTEXPR void on_space() {
+    check_sign();
+    Handler::on_space();
+  }
+
+  FMT_CONSTEXPR void on_hash() {
+    require_numeric_argument();
+    Handler::on_hash();
+  }
+
+  FMT_CONSTEXPR void on_zero() {
+    require_numeric_argument();
+    Handler::on_zero();
+  }
+
+  FMT_CONSTEXPR void end_precision() {
+    if (is_integral(arg_type_) || arg_type_ == pointer_type)
+      this->on_error("precision not allowed for this argument type");
+  }
+
+ private:
+  FMT_CONSTEXPR void require_numeric_argument() {
+    if (!is_arithmetic(arg_type_))
+      this->on_error("format specifier requires numeric argument");
+  }
+
+  FMT_CONSTEXPR void check_sign() {
+    require_numeric_argument();
+    if (is_integral(arg_type_) && arg_type_ != int_type &&
+        arg_type_ != long_long_type && arg_type_ != internal::char_type) {
+      this->on_error("format specifier requires signed argument");
+    }
+  }
+
+  internal::type arg_type_;
+};
+
+template <template <typename> class Handler, typename T,
+          typename Context, typename ErrorHandler>
+FMT_CONSTEXPR void set_dynamic_spec(
+    T &value, basic_format_arg<Context> arg, ErrorHandler eh) {
+  unsigned long long big_value = visit(Handler<ErrorHandler>(eh), arg);
+  if (big_value > (std::numeric_limits<int>::max)())
+    eh.on_error("number is too big");
+  value = static_cast<T>(big_value);
+}
+
+struct auto_id {};
+
+// The standard format specifier handler with checking.
+template <typename Context>
+class specs_handler: public specs_setter<typename Context::char_type> {
+ public:
+  typedef typename Context::char_type char_type;
+
+  FMT_CONSTEXPR specs_handler(basic_format_specs<char_type> &specs, Context &ctx)
+    : specs_setter<char_type>(specs), context_(ctx) {}
+
+  template <typename Id>
+  FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
+    set_dynamic_spec<width_checker>(
+          this->specs_.width_, get_arg(arg_id), context_.error_handler());
+  }
+
+  template <typename Id>
+  FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
+    set_dynamic_spec<precision_checker>(
+          this->specs_.precision_, get_arg(arg_id), context_.error_handler());
+  }
+
+  void on_error(const char *message) {
+    context_.on_error(message);
+  }
+
+ private:
+  FMT_CONSTEXPR basic_format_arg<Context> get_arg(auto_id) {
+    return context_.next_arg();
+  }
+
+  template <typename Id>
+  FMT_CONSTEXPR basic_format_arg<Context> get_arg(Id arg_id) {
+    context_.parse_context().check_arg_id(arg_id);
+    return context_.get_arg(arg_id);
+  }
+
+  Context &context_;
+};
+
+// An argument reference.
+template <typename Char>
+struct arg_ref {
+  enum Kind { NONE, INDEX, NAME };
+
+  FMT_CONSTEXPR arg_ref() : kind(NONE), index(0) {}
+  FMT_CONSTEXPR explicit arg_ref(unsigned index) : kind(INDEX), index(index) {}
+  explicit arg_ref(basic_string_view<Char> name) : kind(NAME), name(name) {}
+
+  FMT_CONSTEXPR arg_ref &operator=(unsigned idx) {
+    kind = INDEX;
+    index = idx;
+    return *this;
+  }
+
+  Kind kind;
+  FMT_UNION {
+    unsigned index;
+    basic_string_view<Char> name;
+  };
+};
+
+// Format specifiers with width and precision resolved at formatting rather
+// than parsing time to allow re-using the same parsed specifiers with
+// differents sets of arguments (precompilation of format strings).
+template <typename Char>
+struct dynamic_format_specs : basic_format_specs<Char> {
+  arg_ref<Char> width_ref;
+  arg_ref<Char> precision_ref;
+};
+
+// Format spec handler that saves references to arguments representing dynamic
+// width and precision to be resolved at formatting time.
+template <typename ParseContext>
+class dynamic_specs_handler :
+    public specs_setter<typename ParseContext::char_type> {
+ public:
+  typedef typename ParseContext::char_type char_type;
+
+  FMT_CONSTEXPR dynamic_specs_handler(
+      dynamic_format_specs<char_type> &specs, ParseContext &ctx)
+    : specs_setter<char_type>(specs), specs_(specs), context_(ctx) {}
+
+  FMT_CONSTEXPR dynamic_specs_handler(const dynamic_specs_handler &other)
+    : specs_setter<char_type>(other),
+      specs_(other.specs_), context_(other.context_) {}
+
+  template <typename Id>
+  FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
+    specs_.width_ref = make_arg_ref(arg_id);
+  }
+
+  template <typename Id>
+  FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
+    specs_.precision_ref = make_arg_ref(arg_id);
+  }
+
+  FMT_CONSTEXPR void on_error(const char *message) {
+    context_.on_error(message);
+  }
+
+ private:
+  typedef arg_ref<char_type> arg_ref_type;
+
+  template <typename Id>
+  FMT_CONSTEXPR arg_ref_type make_arg_ref(Id arg_id) {
+    context_.check_arg_id(arg_id);
+    return arg_ref_type(arg_id);
+  }
+
+  FMT_CONSTEXPR arg_ref_type make_arg_ref(auto_id) {
+    return arg_ref_type(context_.next_arg_id());
+  }
+
+  dynamic_format_specs<char_type> &specs_;
+  ParseContext &context_;
+};
+
+template <typename Iterator, typename IDHandler>
+FMT_CONSTEXPR Iterator parse_arg_id(Iterator it, IDHandler &&handler) {
+  typedef typename std::iterator_traits<Iterator>::value_type char_type;
+  char_type c = *it;
+  if (c == '}' || c == ':') {
+    handler();
+    return it;
+  }
+  if (c >= '0' && c <= '9') {
+    unsigned index = parse_nonnegative_int(it, handler);
+    if (*it != '}' && *it != ':') {
+      handler.on_error("invalid format string");
+      return it;
+    }
+    handler(index);
+    return it;
+  }
+  if (!is_name_start(c)) {
+    handler.on_error("invalid format string");
+    return it;
+  }
+  auto start = it;
+  do {
+    c = *++it;
+  } while (is_name_start(c) || ('0' <= c && c <= '9'));
+  handler(basic_string_view<char_type>(pointer_from(start), to_unsigned(it - start)));
+  return it;
+}
+
+// Adapts SpecHandler to IDHandler API for dynamic width.
+template <typename SpecHandler, typename Char>
+struct width_adapter {
+  explicit FMT_CONSTEXPR width_adapter(SpecHandler &h) : handler(h) {}
+
+  FMT_CONSTEXPR void operator()() { handler.on_dynamic_width(auto_id()); }
+  FMT_CONSTEXPR void operator()(unsigned id) { handler.on_dynamic_width(id); }
+  FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+    handler.on_dynamic_width(id);
+  }
+
+  FMT_CONSTEXPR void on_error(const char *message) {
+    handler.on_error(message);
+  }
+
+  SpecHandler &handler;
+};
+
+// Adapts SpecHandler to IDHandler API for dynamic precision.
+template <typename SpecHandler, typename Char>
+struct precision_adapter {
+  explicit FMT_CONSTEXPR precision_adapter(SpecHandler &h) : handler(h) {}
+
+  FMT_CONSTEXPR void operator()() { handler.on_dynamic_precision(auto_id()); }
+  FMT_CONSTEXPR void operator()(unsigned id) {
+    handler.on_dynamic_precision(id);
+  }
+  FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+    handler.on_dynamic_precision(id);
+  }
+
+  FMT_CONSTEXPR void on_error(const char *message) { handler.on_error(message); }
+
+  SpecHandler &handler;
+};
+
+// Parses standard format specifiers and sends notifications about parsed
+// components to handler.
+// it: an iterator pointing to the beginning of a null-terminated range of
+//     characters, possibly emulated via null_terminating_iterator, representing
+//     format specifiers.
+template <typename Iterator, typename SpecHandler>
+FMT_CONSTEXPR Iterator parse_format_specs(Iterator it, SpecHandler &&handler) {
+  typedef typename std::iterator_traits<Iterator>::value_type char_type;
+  char_type c = *it;
+  if (c == '}' || !c)
+    return it;
+
+  // Parse fill and alignment.
+  alignment align = ALIGN_DEFAULT;
+  int i = 1;
+  do {
+    auto p = it + i;
+    switch (*p) {
+      case '<':
+        align = ALIGN_LEFT;
+        break;
+      case '>':
+        align = ALIGN_RIGHT;
+        break;
+      case '=':
+        align = ALIGN_NUMERIC;
+        break;
+      case '^':
+        align = ALIGN_CENTER;
+        break;
+    }
+    if (align != ALIGN_DEFAULT) {
+      if (p != it) {
+        if (c == '{') {
+          handler.on_error("invalid fill character '{'");
+          return it;
+        }
+        it += 2;
+        handler.on_fill(c);
+      } else ++it;
+      handler.on_align(align);
+      break;
+    }
+  } while (--i >= 0);
+
+  // Parse sign.
+  switch (*it) {
+    case '+':
+      handler.on_plus();
+      ++it;
+      break;
+    case '-':
+      handler.on_minus();
+      ++it;
+      break;
+    case ' ':
+      handler.on_space();
+      ++it;
+      break;
+  }
+
+  if (*it == '#') {
+    handler.on_hash();
+    ++it;
+  }
+
+  // Parse zero flag.
+  if (*it == '0') {
+    handler.on_zero();
+    ++it;
+  }
+
+  // Parse width.
+  if ('0' <= *it && *it <= '9') {
+    handler.on_width(parse_nonnegative_int(it, handler));
+  } else if (*it == '{') {
+    it = parse_arg_id(it + 1, width_adapter<SpecHandler, char_type>(handler));
+    if (*it++ != '}') {
+      handler.on_error("invalid format string");
+      return it;
+    }
+  }
+
+  // Parse precision.
+  if (*it == '.') {
+    ++it;
+    if ('0' <= *it && *it <= '9') {
+      handler.on_precision(parse_nonnegative_int(it, handler));
+    } else if (*it == '{') {
+      it = parse_arg_id(
+            it + 1, precision_adapter<SpecHandler, char_type>(handler));
+      if (*it++ != '}') {
+        handler.on_error("invalid format string");
+        return it;
+      }
+    } else {
+      handler.on_error("missing precision specifier");
+      return it;
+    }
+    handler.end_precision();
+  }
+
+  // Parse type.
+  if (*it != '}' && *it)
+    handler.on_type(*it++);
+  return it;
+}
+
+template <typename Handler, typename Char>
+struct id_adapter {
+  FMT_CONSTEXPR explicit id_adapter(Handler &h): handler(h) {}
+
+  FMT_CONSTEXPR void operator()() { handler.on_arg_id(); }
+  FMT_CONSTEXPR void operator()(unsigned id) { handler.on_arg_id(id); }
+  FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+    handler.on_arg_id(id);
+  }
+
+  FMT_CONSTEXPR void on_error(const char *message) {
+    handler.on_error(message);
+  }
+
+  Handler &handler;
+};
+
+template <typename Iterator, typename Handler>
+FMT_CONSTEXPR void parse_format_string(Iterator it, Handler &&handler) {
+  typedef typename std::iterator_traits<Iterator>::value_type char_type;
+  auto start = it;
+  while (*it) {
+    char_type ch = *it++;
+    if (ch != '{' && ch != '}') continue;
+    if (*it == ch) {
+      handler.on_text(start, it);
+      start = ++it;
+      continue;
+    }
+    if (ch == '}') {
+      handler.on_error("unmatched '}' in format string");
+      return;
+    }
+    handler.on_text(start, it - 1);
+
+    it = parse_arg_id(it, id_adapter<Handler, char_type>(handler));
+    if (*it == '}') {
+      handler.on_replacement_field(it);
+    } else if (*it == ':') {
+      ++it;
+      it = handler.on_format_specs(it);
+      if (*it != '}') {
+        handler.on_error("unknown format specifier");
+        return;
+      }
+    } else {
+      handler.on_error("missing '}' in format string");
+      return;
+    }
+
+    start = ++it;
+  }
+  handler.on_text(start, it);
+}
+
+template <typename T, typename ParseContext>
+FMT_CONSTEXPR const typename ParseContext::char_type *
+    parse_format_specs(ParseContext &ctx) {
+  // GCC 7.2 requires initializer.
+  formatter<T, typename ParseContext::char_type> f{};
+  return f.parse(ctx);
+}
+
+template <typename Char, typename ErrorHandler, typename... Args>
+class format_string_checker {
+ public:
+  explicit FMT_CONSTEXPR format_string_checker(
+      basic_string_view<Char> format_str, ErrorHandler eh)
+    : arg_id_(-1), context_(format_str, eh),
+      parse_funcs_{&parse_format_specs<Args, parse_context_type>...} {}
+
+  FMT_CONSTEXPR void on_text(const Char *, const Char *) {}
+
+  FMT_CONSTEXPR void on_arg_id() {
+    arg_id_ = context_.next_arg_id();
+    check_arg_id();
+  }
+  FMT_CONSTEXPR void on_arg_id(unsigned id) {
+    arg_id_ = id;
+    context_.check_arg_id(id);
+    check_arg_id();
+  }
+  FMT_CONSTEXPR void on_arg_id(basic_string_view<Char>) {}
+
+  FMT_CONSTEXPR void on_replacement_field(const Char *) {}
+
+  FMT_CONSTEXPR const Char *on_format_specs(const Char *s) {
+    context_.advance_to(s);
+    return to_unsigned(arg_id_) < NUM_ARGS ?
+          parse_funcs_[arg_id_](context_) : s;
+  }
+
+  FMT_CONSTEXPR void on_error(const char *message) {
+    context_.on_error(message);
+  }
+
+ private:
+  typedef basic_parse_context<Char, ErrorHandler> parse_context_type;
+  enum { NUM_ARGS = sizeof...(Args) };
+
+  FMT_CONSTEXPR void check_arg_id() {
+    if (internal::to_unsigned(arg_id_) >= NUM_ARGS)
+      context_.on_error("argument index out of range");
+  }
+
+  // Format specifier parsing function.
+  typedef const Char *(*parse_func)(parse_context_type &);
+
+  int arg_id_;
+  parse_context_type context_;
+  parse_func parse_funcs_[NUM_ARGS > 0 ? NUM_ARGS : 1];
+};
+
+template <typename Char, typename ErrorHandler, typename... Args>
+FMT_CONSTEXPR bool check_format_string(
+    basic_string_view<Char> s, ErrorHandler eh = ErrorHandler()) {
+  format_string_checker<Char, ErrorHandler, Args...> checker(s, eh);
+  parse_format_string(s.begin(), checker);
+  return true;
+}
+
+template <typename... Args, typename String>
+void check_format_string(String format_str) {
+  FMT_CONSTEXPR_DECL bool invalid_format =
+      internal::check_format_string<char, internal::error_handler, Args...>(
+        string_view(format_str.data(), format_str.size()));
+  (void)invalid_format;
+}
+
+// Specifies whether to format T using the standard formatter.
+// It is not possible to use get_type in formatter specialization directly
+// because of a bug in MSVC.
+template <typename Context, typename T>
+struct format_type :
+  std::integral_constant<bool, get_type<Context, T>::value != custom_type> {};
+
+// Specifies whether to format enums.
+template <typename T, typename Enable = void>
+struct format_enum : std::integral_constant<bool, std::is_enum<T>::value> {};
+
+template <template <typename> class Handler, typename Spec, typename Context>
+void handle_dynamic_spec(
+    Spec &value, arg_ref<typename Context::char_type> ref, Context &ctx) {
+  typedef typename Context::char_type char_type;
+  switch (ref.kind) {
+  case arg_ref<char_type>::NONE:
+    break;
+  case arg_ref<char_type>::INDEX:
+    internal::set_dynamic_spec<Handler>(
+          value, ctx.get_arg(ref.index), ctx.error_handler());
+    break;
+  case arg_ref<char_type>::NAME:
+    internal::set_dynamic_spec<Handler>(
+          value, ctx.get_arg(ref.name), ctx.error_handler());
+    break;
+  }
+}
+}  // namespace internal
+
+/** The default argument formatter. */
+template <typename Range>
+class arg_formatter:
+  public internal::function<
+    typename internal::arg_formatter_base<Range>::iterator>,
+  public internal::arg_formatter_base<Range> {
+ private:
+  typedef typename Range::value_type char_type;
+  typedef internal::arg_formatter_base<Range> base;
+  typedef basic_format_context<typename base::iterator, char_type> context_type;
+
+  context_type &ctx_;
+
+ public:
+  typedef Range range;
+  typedef typename base::iterator iterator;
+  typedef typename base::format_specs format_specs;
+
+  /**
+    \rst
+    Constructs an argument formatter object.
+    *ctx* is a reference to the formatting context,
+    *spec* contains format specifier information for standard argument types.
+    \endrst
+   */
+  arg_formatter(context_type &ctx, format_specs &spec)
+  : base(Range(ctx.out()), spec), ctx_(ctx) {}
+
+  using base::operator();
+
+  /** Formats an argument of a user-defined type. */
+  iterator operator()(typename basic_format_arg<context_type>::handle handle) {
+    handle.format(ctx_);
+    return this->out();
+  }
+};
+
+/**
+ An error returned by an operating system or a language runtime,
+ for example a file opening error.
+*/
+class system_error : public std::runtime_error {
+ private:
+  FMT_API void init(int err_code, string_view format_str, format_args args);
+
+ protected:
+  int error_code_;
+
+  system_error() : std::runtime_error("") {}
+
+ public:
+  /**
+   \rst
+   Constructs a :class:`fmt::system_error` object with a description
+   formatted with `fmt::format_system_error`. *message* and additional
+   arguments passed into the constructor are formatted similarly to
+   `fmt::format`.
+
+   **Example**::
+
+     // This throws a system_error with the description
+     //   cannot open file 'madeup': No such file or directory
+     // or similar (system message may vary).
+     const char *filename = "madeup";
+     std::FILE *file = std::fopen(filename, "r");
+     if (!file)
+       throw fmt::system_error(errno, "cannot open file '{}'", filename);
+   \endrst
+  */
+  template <typename... Args>
+  system_error(int error_code, string_view message, const Args & ... args)
+    : std::runtime_error("") {
+    init(error_code, message, make_format_args(args...));
+  }
+
+  int error_code() const { return error_code_; }
+};
+
+/**
+  \rst
+  Formats an error returned by an operating system or a language runtime,
+  for example a file opening error, and writes it to *out* in the following
+  form:
+
+  .. parsed-literal::
+     *<message>*: *<system-message>*
+
+  where *<message>* is the passed message and *<system-message>* is
+  the system message corresponding to the error code.
+  *error_code* is a system error code as given by ``errno``.
+  If *error_code* is not a valid error code such as -1, the system message
+  may look like "Unknown error -1" and is platform-dependent.
+  \endrst
+ */
+FMT_API void format_system_error(internal::buffer &out, int error_code,
+                                 fmt::string_view message) FMT_NOEXCEPT;
+
+/**
+  This template provides operations for formatting and writing data into a
+  character range.
+ */
+template <typename Range>
+class basic_writer {
+ public:
+  typedef typename Range::value_type char_type;
+  typedef decltype(internal::declval<Range>().begin()) iterator;
+  typedef basic_format_specs<char_type> format_specs;
+
+ private:
+  // Output iterator.
+  iterator out_;
+
+  std::unique_ptr<locale_provider> locale_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(basic_writer);
+
+  iterator out() const { return out_; }
+
+  // Attempts to reserve space for n extra characters in the output range.
+  // Returns a pointer to the reserved range or a reference to out_.
+  auto reserve(std::size_t n) -> decltype(internal::reserve(out_, n)) {
+    return internal::reserve(out_, n);
+  }
+
+  // Writes a value in the format
+  //   <left-padding><value><right-padding>
+  // where <value> is written by f(it).
+  template <typename F>
+  void write_padded(std::size_t size, const align_spec &spec, F f);
+
+  template <typename F>
+  struct padded_int_writer {
+    string_view prefix;
+    char_type fill;
+    std::size_t padding;
+    F f;
+
+    template <typename It>
+    void operator()(It &&it) const {
+      if (prefix.size() != 0)
+        it = std::copy_n(prefix.data(), prefix.size(), it);
+      it = std::fill_n(it, padding, fill);
+      f(it);
+    }
+  };
+
+  // Writes an integer in the format
+  //   <left-padding><prefix><numeric-padding><digits><right-padding>
+  // where <digits> are written by f(it).
+  template <typename Spec, typename F>
+  void write_int(unsigned num_digits, string_view prefix,
+                 const Spec &spec, F f) {
+    std::size_t size = prefix.size() + num_digits;
+    char_type fill = static_cast<char_type>(spec.fill());
+    std::size_t padding = 0;
+    if (spec.align() == ALIGN_NUMERIC) {
+      if (spec.width() > size) {
+        padding = spec.width() - size;
+        size = spec.width();
+      }
+    } else if (spec.precision() > static_cast<int>(num_digits)) {
+      size = prefix.size() + static_cast<std::size_t>(spec.precision());
+      padding = static_cast<std::size_t>(spec.precision()) - num_digits;
+      fill = '0';
+    }
+    align_spec as = spec;
+    if (spec.align() == ALIGN_DEFAULT)
+      as.align_ = ALIGN_RIGHT;
+    write_padded(size, as, padded_int_writer<F>{prefix, fill, padding, f});
+  }
+
+  // Writes a decimal integer.
+  template <typename Int>
+  void write_decimal(Int value) {
+    typedef typename internal::int_traits<Int>::main_type main_type;
+    main_type abs_value = static_cast<main_type>(value);
+    bool is_negative = internal::is_negative(value);
+    if (is_negative)
+      abs_value = 0 - abs_value;
+    unsigned num_digits = internal::count_digits(abs_value);
+    auto &&it = reserve((is_negative ? 1 : 0) + num_digits);
+    if (is_negative)
+      *it++ = '-';
+    internal::format_decimal(it, abs_value, num_digits);
+  }
+
+  // The handle_int_type_spec handler that writes an integer.
+  template <typename Int, typename Spec>
+  struct int_writer {
+    typedef typename internal::int_traits<Int>::main_type unsigned_type;
+
+    basic_writer<Range> &writer;
+    const Spec &spec;
+    unsigned_type abs_value;
+    char prefix[4];
+    unsigned prefix_size;
+
+    string_view get_prefix() const { return string_view(prefix, prefix_size); }
+
+    // Counts the number of digits in abs_value. BITS = log2(radix).
+    template <unsigned BITS>
+    unsigned count_digits() const {
+      unsigned_type n = abs_value;
+      unsigned num_digits = 0;
+      do {
+        ++num_digits;
+      } while ((n >>= BITS) != 0);
+      return num_digits;
+    }
+
+    int_writer(basic_writer<Range> &w, Int value, const Spec &s)
+      : writer(w), spec(s), abs_value(static_cast<unsigned_type>(value)),
+        prefix_size(0) {
+      if (internal::is_negative(value)) {
+        prefix[0] = '-';
+        ++prefix_size;
+        abs_value = 0 - abs_value;
+      } else if (spec.flag(SIGN_FLAG)) {
+        prefix[0] = spec.flag(PLUS_FLAG) ? '+' : ' ';
+        ++prefix_size;
+      }
+    }
+
+    struct dec_writer {
+      unsigned_type abs_value;
+      unsigned num_digits;
+
+      template <typename It>
+      void operator()(It &&it) const {
+        it = internal::format_decimal(it, abs_value, num_digits);
+      }
+    };
+
+    void on_dec() {
+      unsigned num_digits = internal::count_digits(abs_value);
+      writer.write_int(num_digits, get_prefix(), spec,
+                       dec_writer{abs_value, num_digits});
+    }
+
+    struct hex_writer {
+      int_writer &self;
+      unsigned num_digits;
+
+      template <typename It>
+      void operator()(It &&it) const {
+        it = internal::format_uint<4>(it, self.abs_value, num_digits,
+                                      self.spec.type() != 'x');
+      }
+    };
+
+    void on_hex() {
+      if (spec.flag(HASH_FLAG)) {
+        prefix[prefix_size++] = '0';
+        prefix[prefix_size++] = static_cast<char>(spec.type());
+      }
+      unsigned num_digits = count_digits<4>();
+      writer.write_int(num_digits, get_prefix(), spec,
+                       hex_writer{*this, num_digits});
+    }
+
+    template <int BITS>
+    struct bin_writer {
+      unsigned_type abs_value;
+      unsigned num_digits;
+
+      template <typename It>
+      void operator()(It &&it) const {
+        it = internal::format_uint<BITS>(it, abs_value, num_digits);
+      }
+    };
+
+    void on_bin() {
+      if (spec.flag(HASH_FLAG)) {
+        prefix[prefix_size++] = '0';
+        prefix[prefix_size++] = static_cast<char>(spec.type());
+      }
+      unsigned num_digits = count_digits<1>();
+      writer.write_int(num_digits, get_prefix(), spec,
+                       bin_writer<1>{abs_value, num_digits});
+    }
+
+    void on_oct() {
+      unsigned num_digits = count_digits<3>();
+      if (spec.flag(HASH_FLAG) &&
+          spec.precision() <= static_cast<int>(num_digits)) {
+        // Octal prefix '0' is counted as a digit, so only add it if precision
+        // is not greater than the number of digits.
+        prefix[prefix_size++] = '0';
+      }
+      writer.write_int(num_digits, get_prefix(), spec,
+                       bin_writer<3>{abs_value, num_digits});
+    }
+
+    enum { SEP_SIZE = 1 };
+
+    struct num_writer {
+      unsigned_type abs_value;
+      unsigned size;
+      char_type sep;
+
+      template <typename It>
+      void operator()(It &&it) const {
+        basic_string_view<char_type> s(&sep, SEP_SIZE);
+        it = format_decimal(it, abs_value, size,
+                            internal::add_thousands_sep<char_type>(s));
+      }
+    };
+
+    void on_num() {
+      unsigned num_digits = internal::count_digits(abs_value);
+      char_type sep = internal::thousands_sep<char_type>(writer.locale_.get());
+      unsigned size = num_digits + SEP_SIZE * ((num_digits - 1) / 3);
+      writer.write_int(size, get_prefix(), spec,
+                       num_writer{abs_value, size, sep});
+    }
+
+    void on_error() {
+      FMT_THROW(format_error("invalid type specifier"));
+    }
+  };
+
+  // Writes a formatted integer.
+  template <typename T, typename Spec>
+  void write_int(T value, const Spec &spec) {
+    internal::handle_int_type_spec(spec.type(),
+                                   int_writer<T, Spec>(*this, value, spec));
+  }
+
+  enum {INF_SIZE = 3}; // This is an enum to workaround a bug in MSVC.
+
+  struct inf_or_nan_writer {
+    char sign;
+    const char *str;
+
+    template <typename It>
+    void operator()(It &&it) const {
+      if (sign)
+        *it++ = sign;
+      it = std::copy_n(str, static_cast<std::size_t>(INF_SIZE), it);
+    }
+  };
+
+  struct double_writer {
+    size_t n;
+    char sign;
+    basic_memory_buffer<char_type> &buffer;
+
+    template <typename It>
+    void operator()(It &&it) {
+      if (sign) {
+        *it++ = sign;
+        --n;
+      }
+      it = std::copy_n(buffer.begin(), n, it);
+    }
+  };
+
+  // Formats a floating-point number (double or long double).
+  template <typename T>
+  void write_double(T value, const format_specs &spec);
+  template <typename T>
+  void write_double_sprintf(T value, const format_specs &spec,
+                            internal::basic_buffer<char_type>& buffer);
+
+  template <typename Char>
+  struct str_writer {
+    const Char *s;
+    std::size_t size;
+
+    template <typename It>
+    void operator()(It &&it) const {
+      it = std::copy_n(s, size, it);
+    }
+  };
+
+  // Writes a formatted string.
+  template <typename Char>
+  void write_str(const Char *s, std::size_t size, const align_spec &spec) {
+    write_padded(size, spec, str_writer<Char>{s, size});
+  }
+
+  template <typename Char>
+  void write_str(basic_string_view<Char> str, const format_specs &spec);
+
+  // Appends floating-point length specifier to the format string.
+  // The second argument is only used for overload resolution.
+  void append_float_length(char_type *&format_ptr, long double) {
+    *format_ptr++ = 'L';
+  }
+
+  template<typename T>
+  void append_float_length(char_type *&, T) {}
+
+  template <typename Char>
+  friend class internal::arg_formatter_base;
+
+ public:
+  /** Constructs a ``basic_writer`` object. */
+  explicit basic_writer(Range out): out_(out.begin()) {}
+
+  void write(int value) { write_decimal(value); }
+  void write(long value) { write_decimal(value); }
+  void write(long long value) { write_decimal(value); }
+
+  void write(unsigned value) { write_decimal(value); }
+  void write(unsigned long value) { write_decimal(value); }
+  void write(unsigned long long value) { write_decimal(value); }
+
+  /**
+    \rst
+    Formats *value* and writes it to the buffer.
+    \endrst
+   */
+  template <typename T, typename FormatSpec, typename... FormatSpecs>
+  typename std::enable_if<std::is_integral<T>::value, void>::type
+      write(T value, FormatSpec spec, FormatSpecs... specs) {
+    format_specs s(spec, specs...);
+    s.align_ = ALIGN_RIGHT;
+    write_int(value, s);
+  }
+
+  void write(double value) {
+    write_double(value, format_specs());
+  }
+
+  /**
+    \rst
+    Formats *value* using the general format for floating-point numbers
+    (``'g'``) and writes it to the buffer.
+    \endrst
+   */
+  void write(long double value) {
+    write_double(value, format_specs());
+  }
+
+  /** Writes a character to the buffer. */
+  void write(char value) {
+    *reserve(1) = value;
+  }
+
+  void write(wchar_t value) {
+    internal::require_wchar<char_type>();
+    *reserve(1) = value;
+  }
+
+  /**
+    \rst
+    Writes *value* to the buffer.
+    \endrst
+   */
+  void write(string_view value) {
+    auto &&it = reserve(value.size());
+    it = std::copy(value.begin(), value.end(), it);
+  }
+
+  void write(wstring_view value) {
+    internal::require_wchar<char_type>();
+    auto &&it = reserve(value.size());
+    it = std::uninitialized_copy(value.begin(), value.end(), it);
+  }
+
+  template <typename... FormatSpecs>
+  void write(basic_string_view<char_type> str, FormatSpecs... specs) {
+    write_str(str, format_specs(specs...));
+  }
+
+  template <typename T>
+  typename std::enable_if<std::is_same<T, void>::value>::type write(const T* p) {
+    format_specs specs;
+    specs.flags_ = HASH_FLAG;
+    specs.type_ = 'x';
+    write_int(reinterpret_cast<uintptr_t>(p), specs);
+  }
+};
+
+template <typename Range>
+template <typename F>
+void basic_writer<Range>::write_padded(
+    std::size_t size, const align_spec &spec, F f) {
+  unsigned width = spec.width();
+  if (width <= size)
+    return f(reserve(size));
+  auto &&it = reserve(width);
+  char_type fill = static_cast<char_type>(spec.fill());
+  std::size_t padding = width - size;
+  if (spec.align() == ALIGN_RIGHT) {
+    it = std::fill_n(it, padding, fill);
+    f(it);
+  } else if (spec.align() == ALIGN_CENTER) {
+    std::size_t left_padding = padding / 2;
+    it = std::fill_n(it, left_padding, fill);
+    f(it);
+    it = std::fill_n(it, padding - left_padding, fill);
+  } else {
+    f(it);
+    it = std::fill_n(it, padding, fill);
+  }
+}
+
+template <typename Range>
+template <typename Char>
+void basic_writer<Range>::write_str(
+    basic_string_view<Char> s, const format_specs &spec) {
+  const Char *data = s.data();
+  std::size_t size = s.size();
+  std::size_t precision = static_cast<std::size_t>(spec.precision_);
+  if (spec.precision_ >= 0 && precision < size)
+    size = precision;
+  write_str(data, size, spec);
+}
+
+template <typename Char>
+struct float_spec_handler {
+  Char type;
+  bool upper;
+
+  explicit float_spec_handler(Char t) : type(t), upper(false) {}
+
+  void on_general() {
+    if (type == 'G')
+      upper = true;
+    else
+      type = 'g';
+  }
+
+  void on_exp() {
+    if (type == 'E')
+      upper = true;
+  }
+
+  void on_fixed() {
+    if (type == 'F') {
+      upper = true;
+#if FMT_MSC_VER
+      // MSVC's printf doesn't support 'F'.
+      type = 'f';
+#endif
+    }
+  }
+
+  void on_hex() {
+    if (type == 'A')
+      upper = true;
+  }
+
+  void on_error() {
+    FMT_THROW(format_error("invalid type specifier"));
+  }
+};
+
+template <typename Range>
+template <typename T>
+void basic_writer<Range>::write_double(T value, const format_specs &spec) {
+  // Check type.
+  float_spec_handler<char_type> handler(spec.type());
+  internal::handle_float_type_spec(spec.type(), handler);
+
+  char sign = 0;
+  // Use isnegative instead of value < 0 because the latter is always
+  // false for NaN.
+  if (internal::fputil::isnegative(static_cast<double>(value))) {
+    sign = '-';
+    value = -value;
+  } else if (spec.flag(SIGN_FLAG)) {
+    sign = spec.flag(PLUS_FLAG) ? '+' : ' ';
+  }
+
+  struct write_inf_or_nan_t {
+    basic_writer &writer;
+    format_specs spec;
+    char sign;
+    void operator()(const char *str) const {
+      writer.write_padded(INF_SIZE + (sign ? 1 : 0), spec,
+                          inf_or_nan_writer{sign, str});
+    }
+  } write_inf_or_nan = {*this, spec, sign};
+
+  // Format NaN and ininity ourselves because sprintf's output is not consistent
+  // across platforms.
+  if (internal::fputil::isnotanumber(value))
+    return write_inf_or_nan(handler.upper ? "NAN" : "nan");
+  if (internal::fputil::isinfinity(value))
+    return write_inf_or_nan(handler.upper ? "INF" : "inf");
+
+  basic_memory_buffer<char_type> buffer;
+  if (FMT_USE_GRISU && sizeof(T) <= sizeof(double) &&
+      std::numeric_limits<double>::is_iec559) {
+    internal::fp fp_value(static_cast<double>(value));
+    fp_value.normalize();
+    // Find a cached power of 10 close to 1 / fp_value.
+    int dec_exp = 0;
+    const int min_exp = -60;
+    auto dec_pow = internal::get_cached_power(
+        min_exp - (fp_value.e + internal::fp::significand_size), dec_exp);
+    internal::fp product = fp_value * dec_pow;
+    // Generate output.
+    internal::fp one(1ull << -product.e, product.e);
+    uint64_t hi = product.f >> -one.e;
+    uint64_t f = product.f & (one.f - 1);
+    typedef back_insert_range<internal::basic_buffer<char_type>> range;
+    basic_writer<range> w{range(buffer)};
+    w.write(hi);
+    size_t digits = buffer.size();
+    w.write('.');
+    const unsigned max_digits = 18;
+    while (digits++ < max_digits) {
+      f *= 10;
+      w.write(static_cast<char>('0' + (f >> -one.e)));
+      f &= one.f - 1;
+    }
+    w.write('e');
+    w.write(-dec_exp);
+  } else {
+    format_specs normalized_spec(spec);
+    normalized_spec.type_ = handler.type;
+    write_double_sprintf(value, normalized_spec, buffer);
+  }
+  size_t n = buffer.size();
+  align_spec as = spec;
+  if (spec.align() == ALIGN_NUMERIC) {
+    if (sign) {
+      auto &&it = reserve(1);
+      *it++ = sign;
+      sign = 0;
+      if (as.width_)
+        --as.width_;
+    }
+    as.align_ = ALIGN_RIGHT;
+  } else {
+    if (spec.align() == ALIGN_DEFAULT)
+      as.align_ = ALIGN_RIGHT;
+    if (sign)
+      ++n;
+  }
+  write_padded(n, as, double_writer{n, sign, buffer});
+}
+
+template <typename Range>
+template <typename T>
+void basic_writer<Range>::write_double_sprintf(
+    T value, const format_specs &spec,
+    internal::basic_buffer<char_type>& buffer) {
+  // Buffer capacity must be non-zero, otherwise MSVC's vsnprintf_s will fail.
+  FMT_ASSERT(buffer.capacity() != 0, "empty buffer");
+
+  // Build format string.
+  enum { MAX_FORMAT_SIZE = 10}; // longest format: %#-*.*Lg
+  char_type format[MAX_FORMAT_SIZE];
+  char_type *format_ptr = format;
+  *format_ptr++ = '%';
+  if (spec.flag(HASH_FLAG))
+    *format_ptr++ = '#';
+  if (spec.precision() >= 0) {
+    *format_ptr++ = '.';
+    *format_ptr++ = '*';
+  }
+
+  append_float_length(format_ptr, value);
+  *format_ptr++ = spec.type();
+  *format_ptr = '\0';
+
+  // Format using snprintf.
+  char_type *start = FMT_NULL;
+  for (;;) {
+    std::size_t buffer_size = buffer.capacity();
+    start = &buffer[0];
+    int result = internal::char_traits<char_type>::format_float(
+        start, buffer_size, format, spec.precision(), value);
+    if (result >= 0) {
+      unsigned n = internal::to_unsigned(result);
+      if (n < buffer.capacity()) {
+        buffer.resize(n);
+        break;  // The buffer is large enough - continue with formatting.
+      }
+      buffer.reserve(n + 1);
+    } else {
+      // If result is negative we ask to increase the capacity by at least 1,
+      // but as std::vector, the buffer grows exponentially.
+      buffer.reserve(buffer.capacity() + 1);
+    }
+  }
+}
+
+// Reports a system error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_system_error(int error_code,
+                                 string_view message) FMT_NOEXCEPT;
+
+#if FMT_USE_WINDOWS_H
+
+/** A Windows error. */
+class windows_error : public system_error {
+ private:
+  FMT_API void init(int error_code, string_view format_str, format_args args);
+
+ public:
+  /**
+   \rst
+   Constructs a :class:`fmt::windows_error` object with the description
+   of the form
+
+   .. parsed-literal::
+     *<message>*: *<system-message>*
+
+   where *<message>* is the formatted message and *<system-message>* is the
+   system message corresponding to the error code.
+   *error_code* is a Windows error code as given by ``GetLastError``.
+   If *error_code* is not a valid error code such as -1, the system message
+   will look like "error -1".
+
+   **Example**::
+
+     // This throws a windows_error with the description
+     //   cannot open file 'madeup': The system cannot find the file specified.
+     // or similar (system message may vary).
+     const char *filename = "madeup";
+     LPOFSTRUCT of = LPOFSTRUCT();
+     HFILE file = OpenFile(filename, &of, OF_READ);
+     if (file == HFILE_ERROR) {
+       throw fmt::windows_error(GetLastError(),
+                                "cannot open file '{}'", filename);
+     }
+   \endrst
+  */
+  template <typename... Args>
+  windows_error(int error_code, string_view message, const Args & ... args) {
+    init(error_code, message, make_format_args(args...));
+  }
+};
+
+// Reports a Windows error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_windows_error(int error_code,
+                                  string_view message) FMT_NOEXCEPT;
+
+#endif
+
+/** Fast integer formatter. */
+class format_int {
+ private:
+  // Buffer should be large enough to hold all digits (digits10 + 1),
+  // a sign and a null character.
+  enum {BUFFER_SIZE = std::numeric_limits<unsigned long long>::digits10 + 3};
+  mutable char buffer_[BUFFER_SIZE];
+  char *str_;
+
+  // Formats value in reverse and returns a pointer to the beginning.
+  char *format_decimal(unsigned long long value) {
+    char *ptr = buffer_ + BUFFER_SIZE - 1;
+    while (value >= 100) {
+      // Integer division is slow so do it for a group of two digits instead
+      // of for every digit. The idea comes from the talk by Alexandrescu
+      // "Three Optimization Tips for C++". See speed-test for a comparison.
+      unsigned index = static_cast<unsigned>((value % 100) * 2);
+      value /= 100;
+      *--ptr = internal::data::DIGITS[index + 1];
+      *--ptr = internal::data::DIGITS[index];
+    }
+    if (value < 10) {
+      *--ptr = static_cast<char>('0' + value);
+      return ptr;
+    }
+    unsigned index = static_cast<unsigned>(value * 2);
+    *--ptr = internal::data::DIGITS[index + 1];
+    *--ptr = internal::data::DIGITS[index];
+    return ptr;
+  }
+
+  void format_signed(long long value) {
+    unsigned long long abs_value = static_cast<unsigned long long>(value);
+    bool negative = value < 0;
+    if (negative)
+      abs_value = 0 - abs_value;
+    str_ = format_decimal(abs_value);
+    if (negative)
+      *--str_ = '-';
+  }
+
+ public:
+  explicit format_int(int value) { format_signed(value); }
+  explicit format_int(long value) { format_signed(value); }
+  explicit format_int(long long value) { format_signed(value); }
+  explicit format_int(unsigned value) : str_(format_decimal(value)) {}
+  explicit format_int(unsigned long value) : str_(format_decimal(value)) {}
+  explicit format_int(unsigned long long value) : str_(format_decimal(value)) {}
+
+  /** Returns the number of characters written to the output buffer. */
+  std::size_t size() const {
+    return internal::to_unsigned(buffer_ - str_ + BUFFER_SIZE - 1);
+  }
+
+  /**
+    Returns a pointer to the output buffer content. No terminating null
+    character is appended.
+   */
+  const char *data() const { return str_; }
+
+  /**
+    Returns a pointer to the output buffer content with terminating null
+    character appended.
+   */
+  const char *c_str() const {
+    buffer_[BUFFER_SIZE - 1] = '\0';
+    return str_;
+  }
+
+  /**
+    \rst
+    Returns the content of the output buffer as an ``std::string``.
+    \endrst
+   */
+  std::string str() const { return std::string(str_, size()); }
+};
+
+// Formats a decimal integer value writing into buffer and returns
+// a pointer to the end of the formatted string. This function doesn't
+// write a terminating null character.
+template <typename T>
+inline void format_decimal(char *&buffer, T value) {
+  typedef typename internal::int_traits<T>::main_type main_type;
+  main_type abs_value = static_cast<main_type>(value);
+  if (internal::is_negative(value)) {
+    *buffer++ = '-';
+    abs_value = 0 - abs_value;
+  }
+  if (abs_value < 100) {
+    if (abs_value < 10) {
+      *buffer++ = static_cast<char>('0' + abs_value);
+      return;
+    }
+    unsigned index = static_cast<unsigned>(abs_value * 2);
+    *buffer++ = internal::data::DIGITS[index];
+    *buffer++ = internal::data::DIGITS[index + 1];
+    return;
+  }
+  unsigned num_digits = internal::count_digits(abs_value);
+  internal::format_decimal(buffer, abs_value, num_digits);
+  buffer += num_digits;
+}
+
+// Formatter of objects of type T.
+template <typename T, typename Char>
+struct formatter<
+    T, Char,
+    typename std::enable_if<internal::format_type<
+        typename buffer_context<Char>::type, T>::value>::type> {
+
+  // Parses format specifiers stopping either at the end of the range or at the
+  // terminating '}'.
+  template <typename ParseContext>
+  FMT_CONSTEXPR typename ParseContext::iterator parse(ParseContext &ctx) {
+    auto it = internal::null_terminating_iterator<Char>(ctx);
+    typedef internal::dynamic_specs_handler<ParseContext> handler_type;
+    auto type = internal::get_type<
+      typename buffer_context<Char>::type, T>::value;
+    internal::specs_checker<handler_type>
+        handler(handler_type(specs_, ctx), type);
+    it = parse_format_specs(it, handler);
+    auto type_spec = specs_.type();
+    auto eh = ctx.error_handler();
+    switch (type) {
+    case internal::none_type:
+    case internal::named_arg_type:
+      FMT_ASSERT(false, "invalid argument type");
+      break;
+    case internal::int_type:
+    case internal::uint_type:
+    case internal::long_long_type:
+    case internal::ulong_long_type:
+    case internal::bool_type:
+      handle_int_type_spec(
+            type_spec, internal::int_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::char_type:
+      handle_char_specs(
+          specs_,
+          internal::char_specs_checker<decltype(eh), decltype(type_spec)>(
+              type_spec, eh));
+      break;
+    case internal::double_type:
+    case internal::long_double_type:
+      handle_float_type_spec(
+            type_spec, internal::float_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::cstring_type:
+      internal::handle_cstring_type_spec(
+            type_spec, internal::cstring_type_checker<decltype(eh)>(eh));
+      break;
+    case internal::string_type:
+      internal::check_string_type_spec(type_spec, eh);
+      break;
+    case internal::pointer_type:
+      internal::check_pointer_type_spec(type_spec, eh);
+      break;
+    case internal::custom_type:
+      // Custom format specifiers should be checked in parse functions of
+      // formatter specializations.
+      break;
+    }
+    return pointer_from(it);
+  }
+
+  template <typename FormatContext>
+  auto format(const T &val, FormatContext &ctx) -> decltype(ctx.out()) {
+    internal::handle_dynamic_spec<internal::width_checker>(
+      specs_.width_, specs_.width_ref, ctx);
+    internal::handle_dynamic_spec<internal::precision_checker>(
+      specs_.precision_, specs_.precision_ref, ctx);
+    typedef output_range<typename FormatContext::iterator,
+                         typename FormatContext::char_type> range_type;
+    return visit(arg_formatter<range_type>(ctx, specs_),
+                 internal::make_arg<FormatContext>(val));
+  }
+
+ private:
+  internal::dynamic_format_specs<Char> specs_;
+};
+
+template <typename T, typename Char>
+struct formatter<T, Char,
+    typename std::enable_if<internal::format_enum<T>::value>::type>
+    : public formatter<int, Char> {
+  template <typename ParseContext>
+  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+};
+
+// A formatter for types known only at run time such as variant alternatives.
+//
+// Usage:
+//   typedef std::variant<int, std::string> variant;
+//   template <>
+//   struct formatter<variant>: dynamic_formatter<> {
+//     void format(buffer &buf, const variant &v, context &ctx) {
+//       visit([&](const auto &val) { format(buf, val, ctx); }, v);
+//     }
+//   };
+template <typename Char = char>
+class dynamic_formatter {
+ private:
+  struct null_handler: internal::error_handler {
+    void on_align(alignment) {}
+    void on_plus() {}
+    void on_minus() {}
+    void on_space() {}
+    void on_hash() {}
+  };
+
+ public:
+  template <typename ParseContext>
+  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    auto it = internal::null_terminating_iterator<Char>(ctx);
+    // Checks are deferred to formatting time when the argument type is known.
+    internal::dynamic_specs_handler<ParseContext> handler(specs_, ctx);
+    it = parse_format_specs(it, handler);
+    return pointer_from(it);
+  }
+
+  template <typename T, typename FormatContext>
+  auto format(const T &val, FormatContext &ctx) -> decltype(ctx.out()) {
+    handle_specs(ctx);
+    internal::specs_checker<null_handler>
+        checker(null_handler(), internal::get_type<FormatContext, T>::value);
+    checker.on_align(specs_.align());
+    if (specs_.flags_ == 0) {
+      // Do nothing.
+    } else if (specs_.flag(SIGN_FLAG)) {
+      if (specs_.flag(PLUS_FLAG))
+        checker.on_plus();
+      else
+        checker.on_space();
+    } else if (specs_.flag(MINUS_FLAG)) {
+      checker.on_minus();
+    } else if (specs_.flag(HASH_FLAG)) {
+      checker.on_hash();
+    }
+    if (specs_.precision_ != -1)
+      checker.end_precision();
+    typedef output_range<typename FormatContext::iterator,
+                         typename FormatContext::char_type> range;
+    visit(arg_formatter<range>(ctx, specs_),
+          internal::make_arg<FormatContext>(val));
+    return ctx.out();
+  }
+
+ private:
+  template <typename Context>
+  void handle_specs(Context &ctx) {
+    internal::handle_dynamic_spec<internal::width_checker>(
+      specs_.width_, specs_.width_ref, ctx);
+    internal::handle_dynamic_spec<internal::precision_checker>(
+      specs_.precision_, specs_.precision_ref, ctx);
+  }
+
+  internal::dynamic_format_specs<Char> specs_;
+};
+
+template <typename Range, typename Char>
+typename basic_format_context<Range, Char>::format_arg
+  basic_format_context<Range, Char>::get_arg(basic_string_view<char_type> name) {
+  map_.init(this->args());
+  format_arg arg = map_.find(name);
+  if (arg.type() == internal::none_type)
+    this->on_error("argument not found");
+  return arg;
+}
+
+template <typename ArgFormatter, typename Char, typename Context>
+struct format_handler : internal::error_handler {
+  typedef internal::null_terminating_iterator<Char> iterator;
+  typedef typename ArgFormatter::range range;
+
+  format_handler(range r, basic_string_view<Char> str,
+                 basic_format_args<Context> format_args)
+    : context(r.begin(), str, format_args) {}
+
+  void on_text(iterator begin, iterator end) {
+    auto size = internal::to_unsigned(end - begin);
+    auto out = context.out();
+    auto &&it = internal::reserve(out, size);
+    it = std::copy_n(begin, size, it);
+    context.advance_to(out);
+  }
+
+  void on_arg_id() { arg = context.next_arg(); }
+  void on_arg_id(unsigned id) {
+    context.parse_context().check_arg_id(id);
+    arg = context.get_arg(id);
+  }
+  void on_arg_id(basic_string_view<Char> id) {
+    arg = context.get_arg(id);
+  }
+
+  void on_replacement_field(iterator it) {
+    context.parse_context().advance_to(pointer_from(it));
+    if (visit(internal::custom_formatter<Char, Context>(context), arg))
+      return;
+    basic_format_specs<Char> specs;
+    context.advance_to(visit(ArgFormatter(context, specs), arg));
+  }
+
+  iterator on_format_specs(iterator it) {
+    auto& parse_ctx = context.parse_context();
+    parse_ctx.advance_to(pointer_from(it));
+    if (visit(internal::custom_formatter<Char, Context>(context), arg))
+      return iterator(parse_ctx);
+    basic_format_specs<Char> specs;
+    using internal::specs_handler;
+    internal::specs_checker<specs_handler<Context>>
+        handler(specs_handler<Context>(specs, context), arg.type());
+    it = parse_format_specs(it, handler);
+    if (*it != '}')
+      on_error("missing '}' in format string");
+    parse_ctx.advance_to(pointer_from(it));
+    context.advance_to(visit(ArgFormatter(context, specs), arg));
+    return it;
+  }
+
+  Context context;
+  basic_format_arg<Context> arg;
+};
+
+/** Formats arguments and writes the output to the range. */
+template <typename ArgFormatter, typename Char, typename Context>
+typename Context::iterator vformat_to(typename ArgFormatter::range out,
+                                      basic_string_view<Char> format_str,
+                                      basic_format_args<Context> args) {
+  typedef internal::null_terminating_iterator<Char> iterator;
+  format_handler<ArgFormatter, Char, Context> h(out, format_str, args);
+  parse_format_string(iterator(format_str.begin(), format_str.end()), h);
+  return h.context.out();
+}
+
+// Casts ``p`` to ``const void*`` for pointer formatting.
+// Example:
+//   auto s = format("{}", ptr(p));
+template <typename T>
+inline const void *ptr(const T *p) { return p; }
+
+template <typename It, typename Char>
+struct arg_join {
+  It begin;
+  It end;
+  basic_string_view<Char> sep;
+
+  arg_join(It begin, It end, basic_string_view<Char> sep)
+    : begin(begin), end(end), sep(sep) {}
+};
+
+template <typename It, typename Char>
+struct formatter<arg_join<It, Char>, Char>:
+    formatter<typename std::iterator_traits<It>::value_type, Char> {
+  template <typename FormatContext>
+  auto format(const arg_join<It, Char> &value, FormatContext &ctx)
+      -> decltype(ctx.out()) {
+    typedef formatter<typename std::iterator_traits<It>::value_type, Char> base;
+    auto it = value.begin;
+    auto out = ctx.out();
+    if (it != value.end) {
+      out = base::format(*it++, ctx);
+      while (it != value.end) {
+        out = std::copy(value.sep.begin(), value.sep.end(), out);
+        ctx.advance_to(out);
+        out = base::format(*it++, ctx);
+      }
+    }
+    return out;
+  }
+};
+
+template <typename It>
+arg_join<It, char> join(It begin, It end, string_view sep) {
+  return arg_join<It, char>(begin, end, sep);
+}
+
+template <typename It>
+arg_join<It, wchar_t> join(It begin, It end, wstring_view sep) {
+  return arg_join<It, wchar_t>(begin, end, sep);
+}
+
+// The following causes ICE in gcc 4.4.
+#if FMT_USE_TRAILING_RETURN && (!FMT_GCC_VERSION || FMT_GCC_VERSION >= 405)
+template <typename Range>
+auto join(const Range &range, string_view sep)
+    -> arg_join<decltype(internal::begin(range)), char> {
+  return join(internal::begin(range), internal::end(range), sep);
+}
+
+template <typename Range>
+auto join(const Range &range, wstring_view sep)
+    -> arg_join<decltype(internal::begin(range)), wchar_t> {
+  return join(internal::begin(range), internal::end(range), sep);
+}
+#endif
+
+/**
+  \rst
+  Converts *value* to ``std::string`` using the default format for type *T*.
+
+  **Example**::
+
+    #include <fmt/format.h>
+
+    std::string answer = fmt::to_string(42);
+  \endrst
+ */
+template <typename T>
+std::string to_string(const T &value) {
+  std::string str;
+  internal::container_buffer<std::string> buf(str);
+  writer(buf).write(value);
+  return str;
+}
+
+/**
+  Converts *value* to ``std::wstring`` using the default format for type *T*.
+ */
+template <typename T>
+std::wstring to_wstring(const T &value) {
+  std::wstring str;
+  internal::container_buffer<std::wstring> buf(str);
+  wwriter(buf).write(value);
+  return str;
+}
+
+template <typename Char, std::size_t SIZE>
+std::basic_string<Char> to_string(const basic_memory_buffer<Char, SIZE> &buf) {
+  return std::basic_string<Char>(buf.data(), buf.size());
+}
+
+inline format_context::iterator vformat_to(
+    internal::buffer &buf, string_view format_str, format_args args) {
+  typedef back_insert_range<internal::buffer> range;
+  return vformat_to<arg_formatter<range>>(buf, format_str, args);
+}
+
+inline wformat_context::iterator vformat_to(
+    internal::wbuffer &buf, wstring_view format_str, wformat_args args) {
+  typedef back_insert_range<internal::wbuffer> range;
+  return vformat_to<arg_formatter<range>>(buf, format_str, args);
+}
+
+template <typename... Args, std::size_t SIZE = inline_buffer_size>
+inline format_context::iterator format_to(
+    basic_memory_buffer<char, SIZE> &buf, string_view format_str,
+    const Args & ... args) {
+  return vformat_to(buf, format_str, make_format_args(args...));
+}
+
+template <typename... Args, std::size_t SIZE = inline_buffer_size>
+inline wformat_context::iterator format_to(
+    basic_memory_buffer<wchar_t, SIZE> &buf, wstring_view format_str,
+    const Args & ... args) {
+  return vformat_to(buf, format_str, make_format_args<wformat_context>(args...));
+}
+
+template <typename OutputIt, typename Char = char>
+//using format_context_t = basic_format_context<OutputIt, Char>;
+struct format_context_t { typedef basic_format_context<OutputIt, Char> type; };
+
+template <typename OutputIt, typename Char = char>
+//using format_args_t = basic_format_args<format_context_t<OutputIt, Char>>;
+struct format_args_t {
+  typedef basic_format_args<
+    typename format_context_t<OutputIt, Char>::type> type;
+};
+
+template <typename OutputIt, typename... Args>
+inline OutputIt vformat_to(OutputIt out, string_view format_str,
+                           typename format_args_t<OutputIt>::type args) {
+  typedef output_range<OutputIt, char> range;
+  return vformat_to<arg_formatter<range>>(range(out), format_str, args);
+}
+template <typename OutputIt, typename... Args>
+inline OutputIt vformat_to(
+    OutputIt out, wstring_view format_str,
+    typename format_args_t<OutputIt, wchar_t>::type args) {
+  typedef output_range<OutputIt, wchar_t> range;
+  return vformat_to<arg_formatter<range>>(range(out), format_str, args);
+}
+
+/**
+ \rst
+ Formats arguments, writes the result to the output iterator ``out`` and returns
+ the iterator past the end of the output range.
+
+ **Example**::
+
+   std::vector<char> out;
+   fmt::format_to(std::back_inserter(out), "{}", 42);
+ \endrst
+ */
+template <typename OutputIt, typename... Args>
+inline OutputIt format_to(OutputIt out, string_view format_str,
+                          const Args & ... args) {
+  return vformat_to(out, format_str,
+      make_format_args<typename format_context_t<OutputIt>::type>(args...));
+}
+
+template <typename Container, typename... Args>
+inline typename std::enable_if<
+  is_contiguous<Container>::value, std::back_insert_iterator<Container>>::type
+    format_to(std::back_insert_iterator<Container> out,
+              string_view format_str, const Args & ... args) {
+  return vformat_to(out, format_str, make_format_args<format_context>(args...));
+}
+
+template <typename Container, typename... Args>
+inline typename std::enable_if<
+  is_contiguous<Container>::value, std::back_insert_iterator<Container>>::type
+    format_to(std::back_insert_iterator<Container> out,
+              wstring_view format_str, const Args & ... args) {
+  return vformat_to(out, format_str, make_format_args<wformat_context>(args...));
+}
+
+template <typename OutputIt>
+struct format_to_n_result {
+  /** Iterator past the end of the output range. */
+  OutputIt out;
+  /** Total (not truncated) output size. */
+  std::size_t size;
+};
+
+template <typename OutputIt>
+using format_to_n_context = typename fmt::format_context_t<
+  fmt::internal::truncating_iterator<OutputIt>>::type;
+
+template <typename OutputIt>
+using format_to_n_args = fmt::basic_format_args<format_to_n_context<OutputIt>>;
+
+template <typename OutputIt, typename ...Args>
+inline format_arg_store<format_to_n_context<OutputIt>, Args...>
+    make_format_to_n_args(const Args & ... args) {
+  return format_arg_store<format_to_n_context<OutputIt>, Args...>(args...);
+}
+
+template <typename OutputIt, typename... Args>
+inline format_to_n_result<OutputIt> vformat_to_n(
+    OutputIt out, std::size_t n, string_view format_str,
+    format_to_n_args<OutputIt> args) {
+  typedef internal::truncating_iterator<OutputIt> It;
+  auto it = vformat_to(It(out, n), format_str, args);
+  return {it.base(), it.count()};
+}
+
+/**
+ \rst
+ Formats arguments, writes up to ``n`` characters of the result to the output
+ iterator ``out`` and returns the total output size and the iterator past the end
+ of the output range.
+ \endrst
+ */
+template <typename OutputIt, typename... Args>
+inline format_to_n_result<OutputIt> format_to_n(
+    OutputIt out, std::size_t n, string_view format_str, const Args &... args) {
+  return vformat_to_n<OutputIt>(
+    out, n, format_str, make_format_to_n_args<OutputIt>(args...));
+}
+template <typename OutputIt, typename... Args>
+inline format_to_n_result<OutputIt> format_to_n(
+    OutputIt out, std::size_t n, wstring_view format_str, const Args &... args) {
+  typedef internal::truncating_iterator<OutputIt> It;
+  auto it = vformat_to(It(out, n), format_str,
+      make_format_args<typename format_context_t<It, wchar_t>::type>(args...));
+  return {it.base(), it.count()};
+}
+
+inline std::string vformat(string_view format_str, format_args args) {
+  memory_buffer buffer;
+  vformat_to(buffer, format_str, args);
+  return fmt::to_string(buffer);
+}
+
+inline std::wstring vformat(wstring_view format_str, wformat_args args) {
+  wmemory_buffer buffer;
+  vformat_to(buffer, format_str, args);
+  return to_string(buffer);
+}
+
+template <typename String, typename... Args>
+inline typename std::enable_if<
+  internal::is_format_string<String>::value, std::string>::type
+    format(String format_str, const Args & ... args) {
+  internal::check_format_string<Args...>(format_str);
+  return vformat(format_str.data(), make_format_args(args...));
+}
+
+template <typename String, typename... Args>
+inline typename std::enable_if<internal::is_format_string<String>::value>::type
+    print(String format_str, const Args & ... args) {
+  internal::check_format_string<Args...>(format_str);
+  return vprint(format_str.data(), make_format_args(args...));
+}
+
+/**
+  Returns the number of characters in the output of
+  ``format(format_str, args...)``.
+ */
+template <typename... Args>
+inline std::size_t formatted_size(string_view format_str,
+                                  const Args & ... args) {
+  auto it = format_to(internal::counting_iterator<char>(), format_str, args...);
+  return it.count();
+}
+
+// Experimental color support.
+#ifdef FMT_EXTENDED_COLORS
+enum class color : uint32_t {
+  alice_blue              = 0xF0F8FF, // rgb(240,248,255)
+  antique_white           = 0xFAEBD7, // rgb(250,235,215)
+  aqua                    = 0x00FFFF, // rgb(0,255,255)
+  aquamarine              = 0x7FFFD4, // rgb(127,255,212)
+  azure                   = 0xF0FFFF, // rgb(240,255,255)
+  beige                   = 0xF5F5DC, // rgb(245,245,220)
+  bisque                  = 0xFFE4C4, // rgb(255,228,196)
+  black                   = 0x000000, // rgb(0,0,0)
+  blanched_almond         = 0xFFEBCD, // rgb(255,235,205)
+  blue                    = 0x0000FF, // rgb(0,0,255)
+  blue_violet             = 0x8A2BE2, // rgb(138,43,226)
+  brown                   = 0xA52A2A, // rgb(165,42,42)
+  burly_wood              = 0xDEB887, // rgb(222,184,135)
+  cadet_blue              = 0x5F9EA0, // rgb(95,158,160)
+  chartreuse              = 0x7FFF00, // rgb(127,255,0)
+  chocolate               = 0xD2691E, // rgb(210,105,30)
+  coral                   = 0xFF7F50, // rgb(255,127,80)
+  cornflower_blue         = 0x6495ED, // rgb(100,149,237)
+  cornsilk                = 0xFFF8DC, // rgb(255,248,220)
+  crimson                 = 0xDC143C, // rgb(220,20,60)
+  cyan                    = 0x00FFFF, // rgb(0,255,255)
+  dark_blue               = 0x00008B, // rgb(0,0,139)
+  dark_cyan               = 0x008B8B, // rgb(0,139,139)
+  dark_golden_rod         = 0xB8860B, // rgb(184,134,11)
+  dark_gray               = 0xA9A9A9, // rgb(169,169,169)
+  dark_green              = 0x006400, // rgb(0,100,0)
+  dark_khaki              = 0xBDB76B, // rgb(189,183,107)
+  dark_magenta            = 0x8B008B, // rgb(139,0,139)
+  dark_olive_green        = 0x556B2F, // rgb(85,107,47)
+  dark_orange             = 0xFF8C00, // rgb(255,140,0)
+  dark_orchid             = 0x9932CC, // rgb(153,50,204)
+  dark_red                = 0x8B0000, // rgb(139,0,0)
+  dark_salmon             = 0xE9967A, // rgb(233,150,122)
+  dark_sea_green          = 0x8FBC8F, // rgb(143,188,143)
+  dark_slate_blue         = 0x483D8B, // rgb(72,61,139)
+  dark_slate_gray         = 0x2F4F4F, // rgb(47,79,79)
+  dark_turquoise          = 0x00CED1, // rgb(0,206,209)
+  dark_violet             = 0x9400D3, // rgb(148,0,211)
+  deep_pink               = 0xFF1493, // rgb(255,20,147)
+  deep_sky_blue           = 0x00BFFF, // rgb(0,191,255)
+  dim_gray                = 0x696969, // rgb(105,105,105)
+  dodger_blue             = 0x1E90FF, // rgb(30,144,255)
+  fire_brick              = 0xB22222, // rgb(178,34,34)
+  floral_white            = 0xFFFAF0, // rgb(255,250,240)
+  forest_green            = 0x228B22, // rgb(34,139,34)
+  fuchsia                 = 0xFF00FF, // rgb(255,0,255)
+  gainsboro               = 0xDCDCDC, // rgb(220,220,220)
+  ghost_white             = 0xF8F8FF, // rgb(248,248,255)
+  gold                    = 0xFFD700, // rgb(255,215,0)
+  golden_rod              = 0xDAA520, // rgb(218,165,32)
+  gray                    = 0x808080, // rgb(128,128,128)
+  green                   = 0x008000, // rgb(0,128,0)
+  green_yellow            = 0xADFF2F, // rgb(173,255,47)
+  honey_dew               = 0xF0FFF0, // rgb(240,255,240)
+  hot_pink                = 0xFF69B4, // rgb(255,105,180)
+  indian_red              = 0xCD5C5C, // rgb(205,92,92)
+  indigo                  = 0x4B0082, // rgb(75,0,130)
+  ivory                   = 0xFFFFF0, // rgb(255,255,240)
+  khaki                   = 0xF0E68C, // rgb(240,230,140)
+  lavender                = 0xE6E6FA, // rgb(230,230,250)
+  lavender_blush          = 0xFFF0F5, // rgb(255,240,245)
+  lawn_green              = 0x7CFC00, // rgb(124,252,0)
+  lemon_chiffon           = 0xFFFACD, // rgb(255,250,205)
+  light_blue              = 0xADD8E6, // rgb(173,216,230)
+  light_coral             = 0xF08080, // rgb(240,128,128)
+  light_cyan              = 0xE0FFFF, // rgb(224,255,255)
+  light_golden_rod_yellow = 0xFAFAD2, // rgb(250,250,210)
+  light_gray              = 0xD3D3D3, // rgb(211,211,211)
+  light_green             = 0x90EE90, // rgb(144,238,144)
+  light_pink              = 0xFFB6C1, // rgb(255,182,193)
+  light_salmon            = 0xFFA07A, // rgb(255,160,122)
+  light_sea_green         = 0x20B2AA, // rgb(32,178,170)
+  light_sky_blue          = 0x87CEFA, // rgb(135,206,250)
+  light_slate_gray        = 0x778899, // rgb(119,136,153)
+  light_steel_blue        = 0xB0C4DE, // rgb(176,196,222)
+  light_yellow            = 0xFFFFE0, // rgb(255,255,224)
+  lime                    = 0x00FF00, // rgb(0,255,0)
+  lime_green              = 0x32CD32, // rgb(50,205,50)
+  linen                   = 0xFAF0E6, // rgb(250,240,230)
+  magenta                 = 0xFF00FF, // rgb(255,0,255)
+  maroon                  = 0x800000, // rgb(128,0,0)
+  medium_aquamarine       = 0x66CDAA, // rgb(102,205,170)
+  medium_blue             = 0x0000CD, // rgb(0,0,205)
+  medium_orchid           = 0xBA55D3, // rgb(186,85,211)
+  medium_purple           = 0x9370DB, // rgb(147,112,219)
+  medium_sea_green        = 0x3CB371, // rgb(60,179,113)
+  medium_slate_blue       = 0x7B68EE, // rgb(123,104,238)
+  medium_spring_green     = 0x00FA9A, // rgb(0,250,154)
+  medium_turquoise        = 0x48D1CC, // rgb(72,209,204)
+  medium_violet_red       = 0xC71585, // rgb(199,21,133)
+  midnight_blue           = 0x191970, // rgb(25,25,112)
+  mint_cream              = 0xF5FFFA, // rgb(245,255,250)
+  misty_rose              = 0xFFE4E1, // rgb(255,228,225)
+  moccasin                = 0xFFE4B5, // rgb(255,228,181)
+  navajo_white            = 0xFFDEAD, // rgb(255,222,173)
+  navy                    = 0x000080, // rgb(0,0,128)
+  old_lace                = 0xFDF5E6, // rgb(253,245,230)
+  olive                   = 0x808000, // rgb(128,128,0)
+  olive_drab              = 0x6B8E23, // rgb(107,142,35)
+  orange                  = 0xFFA500, // rgb(255,165,0)
+  orange_red              = 0xFF4500, // rgb(255,69,0)
+  orchid                  = 0xDA70D6, // rgb(218,112,214)
+  pale_golden_rod         = 0xEEE8AA, // rgb(238,232,170)
+  pale_green              = 0x98FB98, // rgb(152,251,152)
+  pale_turquoise          = 0xAFEEEE, // rgb(175,238,238)
+  pale_violet_red         = 0xDB7093, // rgb(219,112,147)
+  papaya_whip             = 0xFFEFD5, // rgb(255,239,213)
+  peach_puff              = 0xFFDAB9, // rgb(255,218,185)
+  peru                    = 0xCD853F, // rgb(205,133,63)
+  pink                    = 0xFFC0CB, // rgb(255,192,203)
+  plum                    = 0xDDA0DD, // rgb(221,160,221)
+  powder_blue             = 0xB0E0E6, // rgb(176,224,230)
+  purple                  = 0x800080, // rgb(128,0,128)
+  rebecca_purple          = 0x663399, // rgb(102,51,153)
+  red                     = 0xFF0000, // rgb(255,0,0)
+  rosy_brown              = 0xBC8F8F, // rgb(188,143,143)
+  royal_blue              = 0x4169E1, // rgb(65,105,225)
+  saddle_brown            = 0x8B4513, // rgb(139,69,19)
+  salmon                  = 0xFA8072, // rgb(250,128,114)
+  sandy_brown             = 0xF4A460, // rgb(244,164,96)
+  sea_green               = 0x2E8B57, // rgb(46,139,87)
+  sea_shell               = 0xFFF5EE, // rgb(255,245,238)
+  sienna                  = 0xA0522D, // rgb(160,82,45)
+  silver                  = 0xC0C0C0, // rgb(192,192,192)
+  sky_blue                = 0x87CEEB, // rgb(135,206,235)
+  slate_blue              = 0x6A5ACD, // rgb(106,90,205)
+  slate_gray              = 0x708090, // rgb(112,128,144)
+  snow                    = 0xFFFAFA, // rgb(255,250,250)
+  spring_green            = 0x00FF7F, // rgb(0,255,127)
+  steel_blue              = 0x4682B4, // rgb(70,130,180)
+  tan                     = 0xD2B48C, // rgb(210,180,140)
+  teal                    = 0x008080, // rgb(0,128,128)
+  thistle                 = 0xD8BFD8, // rgb(216,191,216)
+  tomato                  = 0xFF6347, // rgb(255,99,71)
+  turquoise               = 0x40E0D0, // rgb(64,224,208)
+  violet                  = 0xEE82EE, // rgb(238,130,238)
+  wheat                   = 0xF5DEB3, // rgb(245,222,179)
+  white                   = 0xFFFFFF, // rgb(255,255,255)
+  white_smoke             = 0xF5F5F5, // rgb(245,245,245)
+  yellow                  = 0xFFFF00, // rgb(255,255,0)
+  yellow_green            = 0x9ACD32, // rgb(154,205,50)
+};  // enum class color
+
+// rgb is a struct for red, green and blue colors.
+// We use rgb as name because some editors will show it as color direct in the
+// editor.
+struct rgb {
+  FMT_CONSTEXPR_DECL rgb() : r(0), g(0), b(0) {}
+  FMT_CONSTEXPR_DECL rgb(uint8_t r_, uint8_t g_, uint8_t b_)
+    : r(r_), g(g_), b(b_) {}
+  FMT_CONSTEXPR_DECL rgb(uint32_t hex)
+    : r((hex >> 16) & 0xFF), g((hex >> 8) & 0xFF), b((hex) & 0xFF) {}
+  FMT_CONSTEXPR_DECL rgb(color hex)
+    : r((uint32_t(hex) >> 16) & 0xFF), g((uint32_t(hex) >> 8) & 0xFF),
+      b(uint32_t(hex) & 0xFF) {}
+  uint8_t r;
+  uint8_t g;
+  uint8_t b;
+};
+
+void vprint_rgb(rgb fd, string_view format, format_args args);
+void vprint_rgb(rgb fd, rgb bg, string_view format, format_args args);
+
+/**
+  Formats a string and prints it to stdout using ANSI escape sequences to
+  specify foreground color 'fd'.
+  Example:
+    fmt::print(fmt::color::red, "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename... Args>
+inline void print(rgb fd, string_view format_str, const Args & ... args) {
+  vprint_rgb(fd, format_str, make_format_args(args...));
+}
+
+/**
+  Formats a string and prints it to stdout using ANSI escape sequences to
+  specify foreground color 'fd' and background color 'bg'.
+  Example:
+    fmt::print(fmt::color::red, fmt::color::black, "Elapsed time: {0:.2f} seconds", 1.23);
+ */
+template <typename... Args>
+inline void print(rgb fd, rgb bg, string_view format_str, const Args & ... args) {
+  vprint_rgb(fd, bg, format_str, make_format_args(args...));
+}
+#endif  // FMT_EXTENDED_COLORS
+
+#if FMT_USE_USER_DEFINED_LITERALS
+namespace internal {
+
+# if FMT_UDL_TEMPLATE
+template <typename Char, Char... CHARS>
+class udl_formatter {
+ public:
+  template <typename... Args>
+  std::basic_string<Char> operator()(const Args &... args) const {
+    FMT_CONSTEXPR_DECL Char s[] = {CHARS..., '\0'};
+    FMT_CONSTEXPR_DECL bool invalid_format =
+        check_format_string<Char, error_handler, Args...>(
+          basic_string_view<Char>(s, sizeof...(CHARS)));
+    (void)invalid_format;
+    return format(s, args...);
+  }
+};
+# else
+template <typename Char>
+struct udl_formatter {
+  const Char *str;
+
+  template <typename... Args>
+  auto operator()(Args && ... args) const
+                  -> decltype(format(str, std::forward<Args>(args)...)) {
+    return format(str, std::forward<Args>(args)...);
+  }
+};
+# endif // FMT_UDL_TEMPLATE
+
+template <typename Char>
+struct udl_arg {
+  const Char *str;
+
+  template <typename T>
+  named_arg<T, Char> operator=(T &&value) const {
+    return {str, std::forward<T>(value)};
+  }
+};
+
+} // namespace internal
+
+inline namespace literals {
+
+# if FMT_UDL_TEMPLATE
+template <typename Char, Char... CHARS>
+FMT_CONSTEXPR internal::udl_formatter<Char, CHARS...> operator""_format() {
+  return {};
+}
+# else
+/**
+  \rst
+  User-defined literal equivalent of :func:`fmt::format`.
+
+  **Example**::
+
+    using namespace fmt::literals;
+    std::string message = "The answer is {}"_format(42);
+  \endrst
+ */
+inline internal::udl_formatter<char>
+operator"" _format(const char *s, std::size_t) { return {s}; }
+inline internal::udl_formatter<wchar_t>
+operator"" _format(const wchar_t *s, std::size_t) { return {s}; }
+# endif // FMT_UDL_TEMPLATE
+
+/**
+  \rst
+  User-defined literal equivalent of :func:`fmt::arg`.
+
+  **Example**::
+
+    using namespace fmt::literals;
+    fmt::print("Elapsed time: {s:.2f} seconds", "s"_a=1.23);
+  \endrst
+ */
+inline internal::udl_arg<char>
+operator"" _a(const char *s, std::size_t) { return {s}; }
+inline internal::udl_arg<wchar_t>
+operator"" _a(const wchar_t *s, std::size_t) { return {s}; }
+} // inline namespace literals
+#endif // FMT_USE_USER_DEFINED_LITERALS
+FMT_END_NAMESPACE
+
+#define FMT_STRING(s) [] { \
+    struct S : fmt::format_string { \
+      static FMT_CONSTEXPR decltype(s) data() { return s; } \
+      static FMT_CONSTEXPR size_t size() { return sizeof(s); } \
+    }; \
+    return S{}; \
+  }()
+
+#ifndef FMT_NO_FMT_STRING_ALIAS
+/**
+  \rst
+  Constructs a compile-time format string.
+
+  **Example**::
+
+    #include <fmt/format.h>
+    // A compile-time error because 'd' is an invalid specifier for strings.
+    std::string s = format(fmt("{:d}"), "foo");
+  \endrst
+ */
+# define fmt(s) FMT_STRING(s)
+#endif
+
+#ifdef FMT_HEADER_ONLY
+# define FMT_FUNC inline
+# include "format-inl.h"
+#else
+# define FMT_FUNC
+#endif
+
+// Restore warnings.
+#if FMT_GCC_VERSION >= 406 || FMT_CLANG_VERSION
+# pragma GCC diagnostic pop
+#endif
+
+#endif  // FMT_FORMAT_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/ostream.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,162 @@
+// Formatting library for C++ - std::ostream support
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_OSTREAM_H_
+#define FMT_OSTREAM_H_
+
+#include "format.h"
+#include <ostream>
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+
+template <class Char>
+class formatbuf : public std::basic_streambuf<Char> {
+ private:
+  typedef typename std::basic_streambuf<Char>::int_type int_type;
+  typedef typename std::basic_streambuf<Char>::traits_type traits_type;
+
+  basic_buffer<Char> &buffer_;
+
+ public:
+  formatbuf(basic_buffer<Char> &buffer) : buffer_(buffer) {}
+
+ protected:
+  // The put-area is actually always empty. This makes the implementation
+  // simpler and has the advantage that the streambuf and the buffer are always
+  // in sync and sputc never writes into uninitialized memory. The obvious
+  // disadvantage is that each call to sputc always results in a (virtual) call
+  // to overflow. There is no disadvantage here for sputn since this always
+  // results in a call to xsputn.
+
+  int_type overflow(int_type ch = traits_type::eof()) FMT_OVERRIDE {
+    if (!traits_type::eq_int_type(ch, traits_type::eof()))
+      buffer_.push_back(static_cast<Char>(ch));
+    return ch;
+  }
+
+  std::streamsize xsputn(const Char *s, std::streamsize count) FMT_OVERRIDE {
+    buffer_.append(s, s + count);
+    return count;
+  }
+};
+
+template <typename Char>
+struct test_stream : std::basic_ostream<Char> {
+ private:
+  struct null;
+  // Hide all operator<< from std::basic_ostream<Char>.
+  void operator<<(null);
+};
+
+// Checks if T has a user-defined operator<< (e.g. not a member of std::ostream).
+template <typename T, typename Char>
+class is_streamable {
+ private:
+  template <typename U>
+  static decltype(
+    internal::declval<test_stream<Char>&>()
+      << internal::declval<U>(), std::true_type()) test(int);
+
+  template <typename>
+  static std::false_type test(...);
+
+  typedef decltype(test<T>(0)) result;
+
+ public:
+  // std::string operator<< is not considered user-defined because we handle strings
+  // specially.
+  static const bool value = result::value && !std::is_same<T, std::string>::value;
+};
+
+// Disable conversion to int if T has an overloaded operator<< which is a free
+// function (not a member of std::ostream).
+template <typename T, typename Char>
+class convert_to_int<T, Char, true> {
+ public:
+  static const bool value =
+    convert_to_int<T, Char, false>::value && !is_streamable<T, Char>::value;
+};
+
+// Write the content of buf to os.
+template <typename Char>
+void write(std::basic_ostream<Char> &os, basic_buffer<Char> &buf) {
+  const Char *data = buf.data();
+  typedef std::make_unsigned<std::streamsize>::type UnsignedStreamSize;
+  UnsignedStreamSize size = buf.size();
+  UnsignedStreamSize max_size =
+      internal::to_unsigned((std::numeric_limits<std::streamsize>::max)());
+  do {
+    UnsignedStreamSize n = size <= max_size ? size : max_size;
+    os.write(data, static_cast<std::streamsize>(n));
+    data += n;
+    size -= n;
+  } while (size != 0);
+}
+
+template <typename Char, typename T>
+void format_value(basic_buffer<Char> &buffer, const T &value) {
+  internal::formatbuf<Char> format_buf(buffer);
+  std::basic_ostream<Char> output(&format_buf);
+  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
+  output << value;
+  buffer.resize(buffer.size());
+}
+
+// Disable builtin formatting of enums and use operator<< instead.
+template <typename T>
+struct format_enum<T,
+    typename std::enable_if<std::is_enum<T>::value>::type> : std::false_type {};
+}  // namespace internal
+
+// Formats an object of type T that has an overloaded ostream operator<<.
+template <typename T, typename Char>
+struct formatter<T, Char,
+    typename std::enable_if<internal::is_streamable<T, Char>::value>::type>
+    : formatter<basic_string_view<Char>, Char> {
+
+  template <typename Context>
+  auto format(const T &value, Context &ctx) -> decltype(ctx.out()) {
+    basic_memory_buffer<Char> buffer;
+    internal::format_value(buffer, value);
+    basic_string_view<Char> str(buffer.data(), buffer.size());
+    formatter<basic_string_view<Char>, Char>::format(str, ctx);
+    return ctx.out();
+  }
+};
+
+template <typename Char>
+inline void vprint(std::basic_ostream<Char> &os,
+                   basic_string_view<Char> format_str,
+                   basic_format_args<typename buffer_context<Char>::type> args) {
+  basic_memory_buffer<Char> buffer;
+  vformat_to(buffer, format_str, args);
+  internal::write(os, buffer);
+}
+/**
+  \rst
+  Prints formatted data to the stream *os*.
+
+  **Example**::
+
+    fmt::print(cerr, "Don't {}!", "panic");
+  \endrst
+ */
+template <typename... Args>
+inline void print(std::ostream &os, string_view format_str,
+                  const Args & ... args) {
+  vprint<char>(os, format_str, make_format_args<format_context>(args...));
+}
+
+template <typename... Args>
+inline void print(std::wostream &os, wstring_view format_str,
+                  const Args & ... args) {
+  vprint<wchar_t>(os, format_str, make_format_args<wformat_context>(args...));
+}
+FMT_END_NAMESPACE
+
+#endif  // FMT_OSTREAM_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/posix.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,417 @@
+// A C++ interface to POSIX functions.
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_POSIX_H_
+#define FMT_POSIX_H_
+
+#if defined(__MINGW32__) || defined(__CYGWIN__)
+// Workaround MinGW bug https://sourceforge.net/p/mingw/bugs/2024/.
+# undef __STRICT_ANSI__
+#endif
+
+#include <errno.h>
+#include <fcntl.h>   // for O_RDONLY
+#include <locale.h>  // for locale_t
+#include <stdio.h>
+#include <stdlib.h>  // for strtod_l
+
+#include <cstddef>
+
+#if defined __APPLE__ || defined(__FreeBSD__)
+# include <xlocale.h>  // for LC_NUMERIC_MASK on OS X
+#endif
+
+#include "format.h"
+
+#ifndef FMT_POSIX
+# if defined(_WIN32) && !defined(__MINGW32__)
+// Fix warnings about deprecated symbols.
+#  define FMT_POSIX(call) _##call
+# else
+#  define FMT_POSIX(call) call
+# endif
+#endif
+
+// Calls to system functions are wrapped in FMT_SYSTEM for testability.
+#ifdef FMT_SYSTEM
+# define FMT_POSIX_CALL(call) FMT_SYSTEM(call)
+#else
+# define FMT_SYSTEM(call) call
+# ifdef _WIN32
+// Fix warnings about deprecated symbols.
+#  define FMT_POSIX_CALL(call) ::_##call
+# else
+#  define FMT_POSIX_CALL(call) ::call
+# endif
+#endif
+
+// Retries the expression while it evaluates to error_result and errno
+// equals to EINTR.
+#ifndef _WIN32
+# define FMT_RETRY_VAL(result, expression, error_result) \
+  do { \
+    result = (expression); \
+  } while (result == error_result && errno == EINTR)
+#else
+# define FMT_RETRY_VAL(result, expression, error_result) result = (expression)
+#endif
+
+#define FMT_RETRY(result, expression) FMT_RETRY_VAL(result, expression, -1)
+
+FMT_BEGIN_NAMESPACE
+
+/**
+  \rst
+  A reference to a null-terminated string. It can be constructed from a C
+  string or ``std::string``.
+
+  You can use one of the following typedefs for common character types:
+
+  +---------------+-----------------------------+
+  | Type          | Definition                  |
+  +===============+=============================+
+  | cstring_view  | basic_cstring_view<char>    |
+  +---------------+-----------------------------+
+  | wcstring_view | basic_cstring_view<wchar_t> |
+  +---------------+-----------------------------+
+
+  This class is most useful as a parameter type to allow passing
+  different types of strings to a function, for example::
+
+    template <typename... Args>
+    std::string format(cstring_view format_str, const Args & ... args);
+
+    format("{}", 42);
+    format(std::string("{}"), 42);
+  \endrst
+ */
+template <typename Char>
+class basic_cstring_view {
+ private:
+  const Char *data_;
+
+ public:
+  /** Constructs a string reference object from a C string. */
+  basic_cstring_view(const Char *s) : data_(s) {}
+
+  /**
+    \rst
+    Constructs a string reference from an ``std::string`` object.
+    \endrst
+   */
+  basic_cstring_view(const std::basic_string<Char> &s) : data_(s.c_str()) {}
+
+  /** Returns the pointer to a C string. */
+  const Char *c_str() const { return data_; }
+};
+
+typedef basic_cstring_view<char> cstring_view;
+typedef basic_cstring_view<wchar_t> wcstring_view;
+
+// An error code.
+class error_code {
+ private:
+  int value_;
+
+ public:
+  explicit error_code(int value = 0) FMT_NOEXCEPT : value_(value) {}
+
+  int get() const FMT_NOEXCEPT { return value_; }
+};
+
+// A buffered file.
+class buffered_file {
+ private:
+  FILE *file_;
+
+  friend class file;
+
+  explicit buffered_file(FILE *f) : file_(f) {}
+
+ public:
+  // Constructs a buffered_file object which doesn't represent any file.
+  buffered_file() FMT_NOEXCEPT : file_(FMT_NULL) {}
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~buffered_file() FMT_DTOR_NOEXCEPT;
+
+#if !FMT_USE_RVALUE_REFERENCES
+  // Emulate a move constructor and a move assignment operator if rvalue
+  // references are not supported.
+
+ private:
+  // A proxy object to emulate a move constructor.
+  // It is private to make it impossible call operator Proxy directly.
+  struct Proxy {
+    FILE *file;
+  };
+
+public:
+  // A "move constructor" for moving from a temporary.
+  buffered_file(Proxy p) FMT_NOEXCEPT : file_(p.file) {}
+
+  // A "move constructor" for moving from an lvalue.
+  buffered_file(buffered_file &f) FMT_NOEXCEPT : file_(f.file_) {
+    f.file_ = FMT_NULL;
+  }
+
+  // A "move assignment operator" for moving from a temporary.
+  buffered_file &operator=(Proxy p) {
+    close();
+    file_ = p.file;
+    return *this;
+  }
+
+  // A "move assignment operator" for moving from an lvalue.
+  buffered_file &operator=(buffered_file &other) {
+    close();
+    file_ = other.file_;
+    other.file_ = FMT_NULL;
+    return *this;
+  }
+
+  // Returns a proxy object for moving from a temporary:
+  //   buffered_file file = buffered_file(...);
+  operator Proxy() FMT_NOEXCEPT {
+    Proxy p = {file_};
+    file_ = FMT_NULL;
+    return p;
+  }
+
+#else
+ private:
+  FMT_DISALLOW_COPY_AND_ASSIGN(buffered_file);
+
+ public:
+  buffered_file(buffered_file &&other) FMT_NOEXCEPT : file_(other.file_) {
+    other.file_ = FMT_NULL;
+  }
+
+  buffered_file& operator=(buffered_file &&other) {
+    close();
+    file_ = other.file_;
+    other.file_ = FMT_NULL;
+    return *this;
+  }
+#endif
+
+  // Opens a file.
+  FMT_API buffered_file(cstring_view filename, cstring_view mode);
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the pointer to a FILE object representing this file.
+  FILE *get() const FMT_NOEXCEPT { return file_; }
+
+  // We place parentheses around fileno to workaround a bug in some versions
+  // of MinGW that define fileno as a macro.
+  FMT_API int (fileno)() const;
+
+  void vprint(string_view format_str, format_args args) {
+    fmt::vprint(file_, format_str, args);
+  }
+
+  template <typename... Args>
+  inline void print(string_view format_str, const Args & ... args) {
+    vprint(format_str, make_format_args(args...));
+  }
+};
+
+// A file. Closed file is represented by a file object with descriptor -1.
+// Methods that are not declared with FMT_NOEXCEPT may throw
+// fmt::system_error in case of failure. Note that some errors such as
+// closing the file multiple times will cause a crash on Windows rather
+// than an exception. You can get standard behavior by overriding the
+// invalid parameter handler with _set_invalid_parameter_handler.
+class file {
+ private:
+  int fd_;  // File descriptor.
+
+  // Constructs a file object with a given descriptor.
+  explicit file(int fd) : fd_(fd) {}
+
+ public:
+  // Possible values for the oflag argument to the constructor.
+  enum {
+    RDONLY = FMT_POSIX(O_RDONLY), // Open for reading only.
+    WRONLY = FMT_POSIX(O_WRONLY), // Open for writing only.
+    RDWR   = FMT_POSIX(O_RDWR)    // Open for reading and writing.
+  };
+
+  // Constructs a file object which doesn't represent any file.
+  file() FMT_NOEXCEPT : fd_(-1) {}
+
+  // Opens a file and constructs a file object representing this file.
+  FMT_API file(cstring_view path, int oflag);
+
+#if !FMT_USE_RVALUE_REFERENCES
+  // Emulate a move constructor and a move assignment operator if rvalue
+  // references are not supported.
+
+ private:
+  // A proxy object to emulate a move constructor.
+  // It is private to make it impossible call operator Proxy directly.
+  struct Proxy {
+    int fd;
+  };
+
+ public:
+  // A "move constructor" for moving from a temporary.
+  file(Proxy p) FMT_NOEXCEPT : fd_(p.fd) {}
+
+  // A "move constructor" for moving from an lvalue.
+  file(file &other) FMT_NOEXCEPT : fd_(other.fd_) {
+    other.fd_ = -1;
+  }
+
+  // A "move assignment operator" for moving from a temporary.
+  file &operator=(Proxy p) {
+    close();
+    fd_ = p.fd;
+    return *this;
+  }
+
+  // A "move assignment operator" for moving from an lvalue.
+  file &operator=(file &other) {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+
+  // Returns a proxy object for moving from a temporary:
+  //   file f = file(...);
+  operator Proxy() FMT_NOEXCEPT {
+    Proxy p = {fd_};
+    fd_ = -1;
+    return p;
+  }
+
+#else
+ private:
+  FMT_DISALLOW_COPY_AND_ASSIGN(file);
+
+ public:
+  file(file &&other) FMT_NOEXCEPT : fd_(other.fd_) {
+    other.fd_ = -1;
+  }
+
+  file& operator=(file &&other) {
+    close();
+    fd_ = other.fd_;
+    other.fd_ = -1;
+    return *this;
+  }
+#endif
+
+  // Destroys the object closing the file it represents if any.
+  FMT_API ~file() FMT_DTOR_NOEXCEPT;
+
+  // Returns the file descriptor.
+  int descriptor() const FMT_NOEXCEPT { return fd_; }
+
+  // Closes the file.
+  FMT_API void close();
+
+  // Returns the file size. The size has signed type for consistency with
+  // stat::st_size.
+  FMT_API long long size() const;
+
+  // Attempts to read count bytes from the file into the specified buffer.
+  FMT_API std::size_t read(void *buffer, std::size_t count);
+
+  // Attempts to write count bytes from the specified buffer to the file.
+  FMT_API std::size_t write(const void *buffer, std::size_t count);
+
+  // Duplicates a file descriptor with the dup function and returns
+  // the duplicate as a file object.
+  FMT_API static file dup(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd);
+
+  // Makes fd be the copy of this file descriptor, closing fd first if
+  // necessary.
+  FMT_API void dup2(int fd, error_code &ec) FMT_NOEXCEPT;
+
+  // Creates a pipe setting up read_end and write_end file objects for reading
+  // and writing respectively.
+  FMT_API static void pipe(file &read_end, file &write_end);
+
+  // Creates a buffered_file object associated with this file and detaches
+  // this file object from the file.
+  FMT_API buffered_file fdopen(const char *mode);
+};
+
+// Returns the memory page size.
+long getpagesize();
+
+#if (defined(LC_NUMERIC_MASK) || defined(_MSC_VER)) && \
+    !defined(__ANDROID__) && !defined(__CYGWIN__) && !defined(__OpenBSD__)
+# define FMT_LOCALE
+#endif
+
+#ifdef FMT_LOCALE
+// A "C" numeric locale.
+class Locale {
+ private:
+# ifdef _MSC_VER
+  typedef _locale_t locale_t;
+
+  enum { LC_NUMERIC_MASK = LC_NUMERIC };
+
+  static locale_t newlocale(int category_mask, const char *locale, locale_t) {
+    return _create_locale(category_mask, locale);
+  }
+
+  static void freelocale(locale_t locale) {
+    _free_locale(locale);
+  }
+
+  static double strtod_l(const char *nptr, char **endptr, _locale_t locale) {
+    return _strtod_l(nptr, endptr, locale);
+  }
+# endif
+
+  locale_t locale_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(Locale);
+
+ public:
+  typedef locale_t Type;
+
+  Locale() : locale_(newlocale(LC_NUMERIC_MASK, "C", FMT_NULL)) {
+    if (!locale_)
+      FMT_THROW(system_error(errno, "cannot create locale"));
+  }
+  ~Locale() { freelocale(locale_); }
+
+  Type get() const { return locale_; }
+
+  // Converts string to floating-point number and advances str past the end
+  // of the parsed input.
+  double strtod(const char *&str) const {
+    char *end = FMT_NULL;
+    double result = strtod_l(str, &end, locale_);
+    str = end;
+    return result;
+  }
+};
+#endif  // FMT_LOCALE
+FMT_END_NAMESPACE
+
+#if !FMT_USE_RVALUE_REFERENCES
+namespace std {
+// For compatibility with C++98.
+inline fmt::buffered_file &move(fmt::buffered_file &f) { return f; }
+inline fmt::file &move(fmt::file &f) { return f; }
+}
+#endif
+
+#endif  // FMT_POSIX_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/printf.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,728 @@
+// Formatting library for C++
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_PRINTF_H_
+#define FMT_PRINTF_H_
+
+#include <algorithm>  // std::fill_n
+#include <limits>     // std::numeric_limits
+
+#include "ostream.h"
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+
+// Checks if a value fits in int - used to avoid warnings about comparing
+// signed and unsigned integers.
+template <bool IsSigned>
+struct int_checker {
+  template <typename T>
+  static bool fits_in_int(T value) {
+    unsigned max = std::numeric_limits<int>::max();
+    return value <= max;
+  }
+  static bool fits_in_int(bool) { return true; }
+};
+
+template <>
+struct int_checker<true> {
+  template <typename T>
+  static bool fits_in_int(T value) {
+    return value >= std::numeric_limits<int>::min() &&
+           value <= std::numeric_limits<int>::max();
+  }
+  static bool fits_in_int(int) { return true; }
+};
+
+class printf_precision_handler: public function<int> {
+ public:
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value, int>::type
+      operator()(T value) {
+    if (!int_checker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
+      FMT_THROW(format_error("number is too big"));
+    return static_cast<int>(value);
+  }
+
+  template <typename T>
+  typename std::enable_if<!std::is_integral<T>::value, int>::type operator()(T) {
+    FMT_THROW(format_error("precision is not integer"));
+    return 0;
+  }
+};
+
+// An argument visitor that returns true iff arg is a zero integer.
+class is_zero_int: public function<bool> {
+ public:
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value, bool>::type
+      operator()(T value) { return value == 0; }
+
+  template <typename T>
+  typename std::enable_if<!std::is_integral<T>::value, bool>::type
+      operator()(T) { return false; }
+};
+
+template <typename T>
+struct make_unsigned_or_bool : std::make_unsigned<T> {};
+
+template <>
+struct make_unsigned_or_bool<bool> {
+  typedef bool type;
+};
+
+template <typename T, typename Context>
+class arg_converter: public function<void> {
+ private:
+  typedef typename Context::char_type Char;
+
+  basic_format_arg<Context> &arg_;
+  typename Context::char_type type_;
+
+ public:
+  arg_converter(basic_format_arg<Context> &arg, Char type)
+    : arg_(arg), type_(type) {}
+
+  void operator()(bool value) {
+    if (type_ != 's')
+      operator()<bool>(value);
+  }
+
+  template <typename U>
+  typename std::enable_if<std::is_integral<U>::value>::type
+      operator()(U value) {
+    bool is_signed = type_ == 'd' || type_ == 'i';
+    typedef typename std::conditional<
+        std::is_same<T, void>::value, U, T>::type TargetType;
+    if (const_check(sizeof(TargetType) <= sizeof(int))) {
+      // Extra casts are used to silence warnings.
+      if (is_signed) {
+        arg_ = internal::make_arg<Context>(
+          static_cast<int>(static_cast<TargetType>(value)));
+      } else {
+        typedef typename make_unsigned_or_bool<TargetType>::type Unsigned;
+        arg_ = internal::make_arg<Context>(
+          static_cast<unsigned>(static_cast<Unsigned>(value)));
+      }
+    } else {
+      if (is_signed) {
+        // glibc's printf doesn't sign extend arguments of smaller types:
+        //   std::printf("%lld", -42);  // prints "4294967254"
+        // but we don't have to do the same because it's a UB.
+        arg_ = internal::make_arg<Context>(static_cast<long long>(value));
+      } else {
+        arg_ = internal::make_arg<Context>(
+          static_cast<typename make_unsigned_or_bool<U>::type>(value));
+      }
+    }
+  }
+
+  template <typename U>
+  typename std::enable_if<!std::is_integral<U>::value>::type operator()(U) {
+    // No coversion needed for non-integral types.
+  }
+};
+
+// Converts an integer argument to T for printf, if T is an integral type.
+// If T is void, the argument is converted to corresponding signed or unsigned
+// type depending on the type specifier: 'd' and 'i' - signed, other -
+// unsigned).
+template <typename T, typename Context, typename Char>
+void convert_arg(basic_format_arg<Context> &arg, Char type) {
+  visit(arg_converter<T, Context>(arg, type), arg);
+}
+
+// Converts an integer argument to char for printf.
+template <typename Context>
+class char_converter: public function<void> {
+ private:
+  basic_format_arg<Context> &arg_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(char_converter);
+
+ public:
+  explicit char_converter(basic_format_arg<Context> &arg) : arg_(arg) {}
+
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value>::type
+      operator()(T value) {
+    typedef typename Context::char_type Char;
+    arg_ = internal::make_arg<Context>(static_cast<Char>(value));
+  }
+
+  template <typename T>
+  typename std::enable_if<!std::is_integral<T>::value>::type operator()(T) {
+    // No coversion needed for non-integral types.
+  }
+};
+
+// Checks if an argument is a valid printf width specifier and sets
+// left alignment if it is negative.
+template <typename Char>
+class printf_width_handler: public function<unsigned> {
+ private:
+  typedef basic_format_specs<Char> format_specs;
+
+  format_specs &spec_;
+
+  FMT_DISALLOW_COPY_AND_ASSIGN(printf_width_handler);
+
+ public:
+  explicit printf_width_handler(format_specs &spec) : spec_(spec) {}
+
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value, unsigned>::type
+      operator()(T value) {
+    typedef typename internal::int_traits<T>::main_type UnsignedType;
+    UnsignedType width = static_cast<UnsignedType>(value);
+    if (internal::is_negative(value)) {
+      spec_.align_ = ALIGN_LEFT;
+      width = 0 - width;
+    }
+    unsigned int_max = std::numeric_limits<int>::max();
+    if (width > int_max)
+      FMT_THROW(format_error("number is too big"));
+    return static_cast<unsigned>(width);
+  }
+
+  template <typename T>
+  typename std::enable_if<!std::is_integral<T>::value, unsigned>::type
+      operator()(T) {
+    FMT_THROW(format_error("width is not integer"));
+    return 0;
+  }
+};
+}  // namespace internal
+
+template <typename Range>
+class printf_arg_formatter;
+
+template <
+    typename OutputIt, typename Char,
+    typename ArgFormatter =
+      printf_arg_formatter<back_insert_range<internal::basic_buffer<Char>>>>
+class basic_printf_context;
+
+/**
+  \rst
+  The ``printf`` argument formatter.
+  \endrst
+ */
+template <typename Range>
+class printf_arg_formatter:
+  public internal::function<
+    typename internal::arg_formatter_base<Range>::iterator>,
+  public internal::arg_formatter_base<Range> {
+ private:
+  typedef typename Range::value_type char_type;
+  typedef decltype(internal::declval<Range>().begin()) iterator;
+  typedef internal::arg_formatter_base<Range> base;
+  typedef basic_printf_context<iterator, char_type> context_type;
+
+  context_type &context_;
+
+  void write_null_pointer(char) {
+    this->spec().type_ = 0;
+    this->write("(nil)");
+  }
+
+  void write_null_pointer(wchar_t) {
+    this->spec().type_ = 0;
+    this->write(L"(nil)");
+  }
+
+ public:
+  typedef typename base::format_specs format_specs;
+
+  /**
+    \rst
+    Constructs an argument formatter object.
+    *buffer* is a reference to the output buffer and *spec* contains format
+    specifier information for standard argument types.
+    \endrst
+   */
+  printf_arg_formatter(internal::basic_buffer<char_type> &buffer,
+                       format_specs &spec, context_type &ctx)
+    : base(back_insert_range<internal::basic_buffer<char_type>>(buffer), spec),
+      context_(ctx) {}
+
+  template <typename T>
+  typename std::enable_if<std::is_integral<T>::value, iterator>::type
+      operator()(T value) {
+    // MSVC2013 fails to compile separate overloads for bool and char_type so
+    // use std::is_same instead.
+    if (std::is_same<T, bool>::value) {
+      format_specs &fmt_spec = this->spec();
+      if (fmt_spec.type_ != 's')
+        return base::operator()(value ? 1 : 0);
+      fmt_spec.type_ = 0;
+      this->write(value != 0);
+    } else if (std::is_same<T, char_type>::value) {
+      format_specs &fmt_spec = this->spec();
+      if (fmt_spec.type_ && fmt_spec.type_ != 'c')
+        return (*this)(static_cast<int>(value));
+      fmt_spec.flags_ = 0;
+      fmt_spec.align_ = ALIGN_RIGHT;
+      return base::operator()(value);
+    } else {
+      return base::operator()(value);
+    }
+    return this->out();
+  }
+
+  template <typename T>
+  typename std::enable_if<std::is_floating_point<T>::value, iterator>::type
+      operator()(T value) {
+    return base::operator()(value);
+  }
+
+  /** Formats a null-terminated C string. */
+  iterator operator()(const char *value) {
+    if (value)
+      base::operator()(value);
+    else if (this->spec().type_ == 'p')
+      write_null_pointer(char_type());
+    else
+      this->write("(null)");
+    return this->out();
+  }
+
+  /** Formats a null-terminated wide C string. */
+  iterator operator()(const wchar_t *value) {
+    if (value)
+      base::operator()(value);
+    else if (this->spec().type_ == 'p')
+      write_null_pointer(char_type());
+    else
+      this->write(L"(null)");
+    return this->out();
+  }
+
+  iterator operator()(basic_string_view<char_type> value) {
+    return base::operator()(value);
+  }
+
+  iterator operator()(monostate value) {
+    return base::operator()(value);
+  }
+
+  /** Formats a pointer. */
+  iterator operator()(const void *value) {
+    if (value)
+      return base::operator()(value);
+    this->spec().type_ = 0;
+    write_null_pointer(char_type());
+    return this->out();
+  }
+
+  /** Formats an argument of a custom (user-defined) type. */
+  iterator operator()(typename basic_format_arg<context_type>::handle handle) {
+    handle.format(context_);
+    return this->out();
+  }
+};
+
+template <typename T>
+struct printf_formatter {
+  template <typename ParseContext>
+  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) { return ctx.begin(); }
+
+  template <typename FormatContext>
+  auto format(const T &value, FormatContext &ctx) -> decltype(ctx.out()) {
+    internal::format_value(internal::get_container(ctx.out()), value);
+    return ctx.out();
+  }
+};
+
+/** This template formats data and writes the output to a writer. */
+template <typename OutputIt, typename Char, typename ArgFormatter>
+class basic_printf_context :
+  private internal::context_base<
+    OutputIt, basic_printf_context<OutputIt, Char, ArgFormatter>, Char> {
+ public:
+  /** The character type for the output. */
+  typedef Char char_type;
+
+  template <typename T>
+  struct formatter_type { typedef printf_formatter<T> type; };
+
+ private:
+  typedef internal::context_base<OutputIt, basic_printf_context, Char> base;
+  typedef typename base::format_arg format_arg;
+  typedef basic_format_specs<char_type> format_specs;
+  typedef internal::null_terminating_iterator<char_type> iterator;
+
+  void parse_flags(format_specs &spec, iterator &it);
+
+  // Returns the argument with specified index or, if arg_index is equal
+  // to the maximum unsigned value, the next argument.
+  format_arg get_arg(
+      iterator it,
+      unsigned arg_index = (std::numeric_limits<unsigned>::max)());
+
+  // Parses argument index, flags and width and returns the argument index.
+  unsigned parse_header(iterator &it, format_specs &spec);
+
+ public:
+  /**
+   \rst
+   Constructs a ``printf_context`` object. References to the arguments and
+   the writer are stored in the context object so make sure they have
+   appropriate lifetimes.
+   \endrst
+   */
+  basic_printf_context(OutputIt out, basic_string_view<char_type> format_str,
+                       basic_format_args<basic_printf_context> args)
+    : base(out, format_str, args) {}
+
+  using base::parse_context;
+  using base::out;
+  using base::advance_to;
+
+  /** Formats stored arguments and writes the output to the range. */
+  void format();
+};
+
+template <typename OutputIt, typename Char, typename AF>
+void basic_printf_context<OutputIt, Char, AF>::parse_flags(
+    format_specs &spec, iterator &it) {
+  for (;;) {
+    switch (*it++) {
+      case '-':
+        spec.align_ = ALIGN_LEFT;
+        break;
+      case '+':
+        spec.flags_ |= SIGN_FLAG | PLUS_FLAG;
+        break;
+      case '0':
+        spec.fill_ = '0';
+        break;
+      case ' ':
+        spec.flags_ |= SIGN_FLAG;
+        break;
+      case '#':
+        spec.flags_ |= HASH_FLAG;
+        break;
+      default:
+        --it;
+        return;
+    }
+  }
+}
+
+template <typename OutputIt, typename Char, typename AF>
+typename basic_printf_context<OutputIt, Char, AF>::format_arg
+  basic_printf_context<OutputIt, Char, AF>::get_arg(
+    iterator it, unsigned arg_index) {
+  (void)it;
+  if (arg_index == std::numeric_limits<unsigned>::max())
+    return this->do_get_arg(this->parse_context().next_arg_id());
+  return base::get_arg(arg_index - 1);
+}
+
+template <typename OutputIt, typename Char, typename AF>
+unsigned basic_printf_context<OutputIt, Char, AF>::parse_header(
+  iterator &it, format_specs &spec) {
+  unsigned arg_index = std::numeric_limits<unsigned>::max();
+  char_type c = *it;
+  if (c >= '0' && c <= '9') {
+    // Parse an argument index (if followed by '$') or a width possibly
+    // preceded with '0' flag(s).
+    internal::error_handler eh;
+    unsigned value = parse_nonnegative_int(it, eh);
+    if (*it == '$') {  // value is an argument index
+      ++it;
+      arg_index = value;
+    } else {
+      if (c == '0')
+        spec.fill_ = '0';
+      if (value != 0) {
+        // Nonzero value means that we parsed width and don't need to
+        // parse it or flags again, so return now.
+        spec.width_ = value;
+        return arg_index;
+      }
+    }
+  }
+  parse_flags(spec, it);
+  // Parse width.
+  if (*it >= '0' && *it <= '9') {
+    internal::error_handler eh;
+    spec.width_ = parse_nonnegative_int(it, eh);
+  } else if (*it == '*') {
+    ++it;
+    spec.width_ =
+        visit(internal::printf_width_handler<char_type>(spec), get_arg(it));
+  }
+  return arg_index;
+}
+
+template <typename OutputIt, typename Char, typename AF>
+void basic_printf_context<OutputIt, Char, AF>::format() {
+  auto &buffer = internal::get_container(this->out());
+  auto start = iterator(this->parse_context());
+  auto it = start;
+  using internal::pointer_from;
+  while (*it) {
+    char_type c = *it++;
+    if (c != '%') continue;
+    if (*it == c) {
+      buffer.append(pointer_from(start), pointer_from(it));
+      start = ++it;
+      continue;
+    }
+    buffer.append(pointer_from(start), pointer_from(it) - 1);
+
+    format_specs spec;
+    spec.align_ = ALIGN_RIGHT;
+
+    // Parse argument index, flags and width.
+    unsigned arg_index = parse_header(it, spec);
+
+    // Parse precision.
+    if (*it == '.') {
+      ++it;
+      if ('0' <= *it && *it <= '9') {
+        internal::error_handler eh;
+        spec.precision_ = static_cast<int>(parse_nonnegative_int(it, eh));
+      } else if (*it == '*') {
+        ++it;
+        spec.precision_ =
+            visit(internal::printf_precision_handler(), get_arg(it));
+      } else {
+        spec.precision_ = 0;
+      }
+    }
+
+    format_arg arg = get_arg(it, arg_index);
+    if (spec.flag(HASH_FLAG) && visit(internal::is_zero_int(), arg))
+      spec.flags_ &= ~internal::to_unsigned<int>(HASH_FLAG);
+    if (spec.fill_ == '0') {
+      if (arg.is_arithmetic())
+        spec.align_ = ALIGN_NUMERIC;
+      else
+        spec.fill_ = ' ';  // Ignore '0' flag for non-numeric types.
+    }
+
+    // Parse length and convert the argument to the required type.
+    using internal::convert_arg;
+    switch (*it++) {
+    case 'h':
+      if (*it == 'h')
+        convert_arg<signed char>(arg, *++it);
+      else
+        convert_arg<short>(arg, *it);
+      break;
+    case 'l':
+      if (*it == 'l')
+        convert_arg<long long>(arg, *++it);
+      else
+        convert_arg<long>(arg, *it);
+      break;
+    case 'j':
+      convert_arg<intmax_t>(arg, *it);
+      break;
+    case 'z':
+      convert_arg<std::size_t>(arg, *it);
+      break;
+    case 't':
+      convert_arg<std::ptrdiff_t>(arg, *it);
+      break;
+    case 'L':
+      // printf produces garbage when 'L' is omitted for long double, no
+      // need to do the same.
+      break;
+    default:
+      --it;
+      convert_arg<void>(arg, *it);
+    }
+
+    // Parse type.
+    if (!*it)
+      FMT_THROW(format_error("invalid format string"));
+    spec.type_ = static_cast<char>(*it++);
+    if (arg.is_integral()) {
+      // Normalize type.
+      switch (spec.type_) {
+      case 'i': case 'u':
+        spec.type_ = 'd';
+        break;
+      case 'c':
+        // TODO: handle wchar_t better?
+        visit(internal::char_converter<basic_printf_context>(arg), arg);
+        break;
+      }
+    }
+
+    start = it;
+
+    // Format argument.
+    visit(AF(buffer, spec, *this), arg);
+  }
+  buffer.append(pointer_from(start), pointer_from(it));
+}
+
+template <typename Char, typename Context>
+void printf(internal::basic_buffer<Char> &buf, basic_string_view<Char> format,
+            basic_format_args<Context> args) {
+  Context(std::back_inserter(buf), format, args).format();
+}
+
+template <typename Buffer>
+struct printf_context {
+  typedef basic_printf_context<
+    std::back_insert_iterator<Buffer>, typename Buffer::value_type> type;
+};
+
+template <typename ...Args>
+inline format_arg_store<printf_context<internal::buffer>::type, Args...>
+    make_printf_args(const Args & ... args) {
+  return format_arg_store<printf_context<internal::buffer>::type, Args...>(
+      args...);
+}
+typedef basic_format_args<printf_context<internal::buffer>::type> printf_args;
+typedef basic_format_args<printf_context<internal::wbuffer>::type> wprintf_args;
+
+inline std::string vsprintf(string_view format, printf_args args) {
+  memory_buffer buffer;
+  printf(buffer, format, args);
+  return to_string(buffer);
+}
+
+/**
+  \rst
+  Formats arguments and returns the result as a string.
+
+  **Example**::
+
+    std::string message = fmt::sprintf("The answer is %d", 42);
+  \endrst
+*/
+template <typename... Args>
+inline std::string sprintf(string_view format_str, const Args & ... args) {
+  return vsprintf(format_str,
+    make_format_args<typename printf_context<internal::buffer>::type>(args...));
+}
+
+inline std::wstring vsprintf(wstring_view format, wprintf_args args) {
+  wmemory_buffer buffer;
+  printf(buffer, format, args);
+  return to_string(buffer);
+}
+
+template <typename... Args>
+inline std::wstring sprintf(wstring_view format_str, const Args & ... args) {
+  return vsprintf(format_str,
+    make_format_args<typename printf_context<internal::wbuffer>::type>(args...));
+}
+
+template <typename Char>
+inline int vfprintf(std::FILE *f, basic_string_view<Char> format,
+                    basic_format_args<typename printf_context<
+                      internal::basic_buffer<Char>>::type> args) {
+  basic_memory_buffer<Char> buffer;
+  printf(buffer, format, args);
+  std::size_t size = buffer.size();
+  return std::fwrite(
+    buffer.data(), sizeof(Char), size, f) < size ? -1 : static_cast<int>(size);
+}
+
+/**
+  \rst
+  Prints formatted data to the file *f*.
+
+  **Example**::
+
+    fmt::fprintf(stderr, "Don't %s!", "panic");
+  \endrst
+ */
+template <typename... Args>
+inline int fprintf(std::FILE *f, string_view format_str, const Args & ... args) {
+  auto vargs = make_format_args<
+    typename printf_context<internal::buffer>::type>(args...);
+  return vfprintf<char>(f, format_str, vargs);
+}
+
+template <typename... Args>
+inline int fprintf(std::FILE *f, wstring_view format_str,
+                   const Args & ... args) {
+  return vfprintf(f, format_str,
+    make_format_args<typename printf_context<internal::wbuffer>::type>(args...));
+}
+
+inline int vprintf(string_view format, printf_args args) {
+  return vfprintf(stdout, format, args);
+}
+
+inline int vprintf(wstring_view format, wprintf_args args) {
+  return vfprintf(stdout, format, args);
+}
+
+/**
+  \rst
+  Prints formatted data to ``stdout``.
+
+  **Example**::
+
+    fmt::printf("Elapsed time: %.2f seconds", 1.23);
+  \endrst
+ */
+template <typename... Args>
+inline int printf(string_view format_str, const Args & ... args) {
+  return vprintf(format_str,
+    make_format_args<typename printf_context<internal::buffer>::type>(args...));
+}
+
+template <typename... Args>
+inline int printf(wstring_view format_str, const Args & ... args) {
+  return vprintf(format_str,
+    make_format_args<typename printf_context<internal::wbuffer>::type>(args...));
+}
+
+inline int vfprintf(std::ostream &os, string_view format_str,
+                    printf_args args) {
+  memory_buffer buffer;
+  printf(buffer, format_str, args);
+  internal::write(os, buffer);
+  return static_cast<int>(buffer.size());
+}
+
+inline int vfprintf(std::wostream &os, wstring_view format_str,
+                    wprintf_args args) {
+  wmemory_buffer buffer;
+  printf(buffer, format_str, args);
+  internal::write(os, buffer);
+  return static_cast<int>(buffer.size());
+}
+
+/**
+  \rst
+  Prints formatted data to the stream *os*.
+
+  **Example**::
+
+    fmt::fprintf(cerr, "Don't %s!", "panic");
+  \endrst
+ */
+template <typename... Args>
+inline int fprintf(std::ostream &os, string_view format_str,
+                   const Args & ... args) {
+  auto vargs = make_format_args<
+    typename printf_context<internal::buffer>::type>(args...);
+  return vfprintf(os, format_str, vargs);
+}
+
+template <typename... Args>
+inline int fprintf(std::wostream &os, wstring_view format_str,
+                   const Args & ... args) {
+  auto vargs = make_format_args<
+    typename printf_context<internal::buffer>::type>(args...);
+  return vfprintf(os, format_str, vargs);
+}
+FMT_END_NAMESPACE
+
+#endif  // FMT_PRINTF_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/ranges.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,305 @@
+// Formatting library for C++ - the core API
+//
+// Copyright (c) 2012 - present, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+//
+// Copyright (c) 2018 - present, Remotion (Igor Schulz)
+// All Rights Reserved
+// {fmt} support for ranges, containers and types tuple interface.
+
+#ifndef FMT_RANGES_H_
+#define FMT_RANGES_H_
+
+#include "format.h"
+#include <type_traits>
+
+// output only up to N items from the range.
+#ifndef FMT_RANGE_OUTPUT_LENGTH_LIMIT
+# define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
+#endif
+
+FMT_BEGIN_NAMESPACE
+
+template <typename Char>
+struct formatting_base {
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    return ctx.begin();
+  }
+};
+
+template <typename Char, typename Enable = void>
+struct formatting_range : formatting_base<Char> {
+  static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
+      FMT_RANGE_OUTPUT_LENGTH_LIMIT; // output only up to N items from the range.
+  Char prefix;
+  Char delimiter;
+  Char postfix;
+  formatting_range() : prefix('{'), delimiter(','), postfix('}') {}
+  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
+  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
+};
+
+template <typename Char, typename Enable = void>
+struct formatting_tuple : formatting_base<Char> {
+  Char prefix;
+  Char delimiter;
+  Char postfix;
+  formatting_tuple() : prefix('('), delimiter(','), postfix(')') {}
+  static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
+  static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
+};
+
+namespace internal {
+
+template <typename RangeT, typename OutputIterator>
+void copy(const RangeT &range, OutputIterator out) {
+  for (auto it = range.begin(), end = range.end(); it != end; ++it)
+    *out++ = *it;
+}
+
+template <typename OutputIterator>
+void copy(const char *str, OutputIterator out) {
+  const char *p_curr = str;
+  while (*p_curr) {
+    *out++ = *p_curr++;
+  }
+}
+
+template <typename OutputIterator>
+void copy(char ch, OutputIterator out) {
+  *out++ = ch;
+}
+
+/// Return true value if T has std::string interface, like std::string_view.
+template <typename T>
+class is_like_std_string {
+  template <typename U>
+  static auto check(U *p) ->
+    decltype(p->find('a'), p->length(), p->data(), int());
+  template <typename>
+  static void check(...);
+
+ public:
+  static FMT_CONSTEXPR_DECL const bool value =
+    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+};
+
+template <typename... Ts>
+struct conditional_helper {};
+
+template <typename T, typename _ = void>
+struct is_range_ : std::false_type {};
+
+#if !FMT_MSC_VER || FMT_MSC_VER > 1800
+template <typename T>
+struct is_range_<T, typename std::conditional<
+                    false,
+                    conditional_helper<decltype(internal::declval<T>().begin()),
+                                       decltype(internal::declval<T>().end())>,
+                    void>::type> : std::true_type {};
+#endif
+
+/// tuple_size and tuple_element check.
+template <typename T>
+class is_tuple_like_ {
+  template <typename U>
+  static auto check(U *p) ->
+    decltype(std::tuple_size<U>::value,
+      internal::declval<typename std::tuple_element<0, U>::type>(), int());
+  template <typename>
+  static void check(...);
+
+ public:
+  static FMT_CONSTEXPR_DECL const bool value =
+    !std::is_void<decltype(check<T>(FMT_NULL))>::value;
+};
+
+// Check for integer_sequence
+#if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
+template <typename T, T... N>
+using integer_sequence = std::integer_sequence<T, N...>;
+template <std::size_t... N>
+using index_sequence = std::index_sequence<N...>;
+template <std::size_t N>
+using make_index_sequence = std::make_index_sequence<N>;
+#else
+template <typename T, T... N>
+struct integer_sequence {
+  typedef T value_type;
+
+  static FMT_CONSTEXPR std::size_t size() {
+    return sizeof...(N);
+  }
+};
+
+template <std::size_t... N>
+using index_sequence = integer_sequence<std::size_t, N...>;
+
+template <typename T, std::size_t N, T... Ns>
+struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {};
+template <typename T, T... Ns>
+struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {};
+
+template <std::size_t N>
+using make_index_sequence = make_integer_sequence<std::size_t, N>;
+#endif
+
+template <class Tuple, class F, size_t... Is>
+void for_each(index_sequence<Is...>, Tuple &&tup, F &&f) FMT_NOEXCEPT {
+  using std::get;
+  // using free function get<I>(T) now.
+  const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
+  (void)_;  // blocks warnings
+}
+
+template <class T>
+FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> 
+get_indexes(T const &) { return {}; }
+
+template <class Tuple, class F>
+void for_each(Tuple &&tup, F &&f) {
+  const auto indexes = get_indexes(tup);
+  for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
+}
+
+template<typename Arg>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&, 
+  typename std::enable_if<
+    !is_like_std_string<typename std::decay<Arg>::type>::value>::type* = nullptr) {
+  return add_space ? " {}" : "{}";
+}
+
+template<typename Arg>
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&, 
+  typename std::enable_if<
+    is_like_std_string<typename std::decay<Arg>::type>::value>::type* = nullptr) {
+  return add_space ? " \"{}\"" : "\"{}\"";
+}
+
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char*) {
+  return add_space ? " \"{}\"" : "\"{}\"";
+}
+FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t*) {
+    return add_space ? L" \"{}\"" : L"\"{}\"";
+}
+
+FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
+    return add_space ? " '{}'" : "'{}'";
+}
+FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
+    return add_space ? L" '{}'" : L"'{}'";
+}
+
+}  // namespace internal
+
+template <typename T>
+struct is_tuple_like {
+  static FMT_CONSTEXPR_DECL const bool value =
+    internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
+};
+
+template <typename TupleT, typename Char>
+struct formatter<TupleT, Char, 
+    typename std::enable_if<fmt::is_tuple_like<TupleT>::value>::type> {
+private:
+  // C++11 generic lambda for format()
+  template <typename FormatContext>
+  struct format_each {
+    template <typename T>
+    void operator()(const T& v) {
+      if (i > 0) {
+        if (formatting.add_prepostfix_space) {
+          *out++ = ' ';
+        }
+        internal::copy(formatting.delimiter, out);
+      }
+      format_to(out,
+                internal::format_str_quoted(
+                    (formatting.add_delimiter_spaces && i > 0), v),
+                v);
+      ++i;
+    }
+
+    formatting_tuple<Char>& formatting;
+    std::size_t& i;
+    typename std::add_lvalue_reference<decltype(std::declval<FormatContext>().out())>::type out;
+  };
+
+public:
+  formatting_tuple<Char> formatting;
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    return formatting.parse(ctx);
+  }
+
+  template <typename FormatContext = format_context>
+  auto format(const TupleT &values, FormatContext &ctx) -> decltype(ctx.out()) {
+    auto out = ctx.out();
+    std::size_t i = 0;
+    internal::copy(formatting.prefix, out);
+
+    internal::for_each(values, format_each<FormatContext>{formatting, i, out});
+    if (formatting.add_prepostfix_space) {
+      *out++ = ' ';
+    }
+    internal::copy(formatting.postfix, out);
+
+    return ctx.out();
+  }
+};
+
+template <typename T>
+struct is_range {
+  static FMT_CONSTEXPR_DECL const bool value =
+    internal::is_range_<T>::value && !internal::is_like_std_string<T>::value;
+};
+
+template <typename RangeT, typename Char>
+struct formatter<RangeT, Char,
+    typename std::enable_if<fmt::is_range<RangeT>::value>::type> {
+
+  formatting_range<Char> formatting;
+
+  template <typename ParseContext>
+  FMT_CONSTEXPR auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    return formatting.parse(ctx);
+  }
+
+  template <typename FormatContext>
+  typename FormatContext::iterator format(
+      const RangeT &values, FormatContext &ctx) {
+    auto out = ctx.out();
+    internal::copy(formatting.prefix, out);
+    std::size_t i = 0;
+    for (auto it = values.begin(), end = values.end(); it != end; ++it) {
+      if (i > 0) {
+        if (formatting.add_prepostfix_space) {
+          *out++ = ' ';
+        }
+        internal::copy(formatting.delimiter, out);
+      }
+      format_to(out,
+                internal::format_str_quoted(
+                    (formatting.add_delimiter_spaces && i > 0), *it),
+                *it);
+      if (++i > formatting.range_length_limit) {
+        format_to(out, " ... <other elements>");
+        break;
+      }
+    }
+    if (formatting.add_prepostfix_space) {
+      *out++ = ' ';
+    }
+    internal::copy(formatting.postfix, out);
+    return ctx.out();
+  }
+};
+
+FMT_END_NAMESPACE
+
+#endif // FMT_RANGES_H_
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/include/fmt/time.h	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,152 @@
+// Formatting library for C++ - time formatting
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#ifndef FMT_TIME_H_
+#define FMT_TIME_H_
+
+#include "format.h"
+#include <ctime>
+
+FMT_BEGIN_NAMESPACE
+
+namespace internal{
+inline null<> localtime_r(...) { return null<>(); }
+inline null<> localtime_s(...) { return null<>(); }
+inline null<> gmtime_r(...) { return null<>(); }
+inline null<> gmtime_s(...) { return null<>(); }
+}
+
+// Thread-safe replacement for std::localtime
+inline std::tm localtime(std::time_t time) {
+  struct dispatcher {
+    std::time_t time_;
+    std::tm tm_;
+
+    dispatcher(std::time_t t): time_(t) {}
+
+    bool run() {
+      using namespace fmt::internal;
+      return handle(localtime_r(&time_, &tm_));
+    }
+
+    bool handle(std::tm *tm) { return tm != FMT_NULL; }
+
+    bool handle(internal::null<>) {
+      using namespace fmt::internal;
+      return fallback(localtime_s(&tm_, &time_));
+    }
+
+    bool fallback(int res) { return res == 0; }
+
+    bool fallback(internal::null<>) {
+      using namespace fmt::internal;
+      std::tm *tm = std::localtime(&time_);
+      if (tm) tm_ = *tm;
+      return tm != FMT_NULL;
+    }
+  };
+  dispatcher lt(time);
+  if (lt.run())
+    return lt.tm_;
+  // Too big time values may be unsupported.
+  FMT_THROW(format_error("time_t value out of range"));
+}
+
+// Thread-safe replacement for std::gmtime
+inline std::tm gmtime(std::time_t time) {
+  struct dispatcher {
+    std::time_t time_;
+    std::tm tm_;
+
+    dispatcher(std::time_t t): time_(t) {}
+
+    bool run() {
+      using namespace fmt::internal;
+      return handle(gmtime_r(&time_, &tm_));
+    }
+
+    bool handle(std::tm *tm) { return tm != FMT_NULL; }
+
+    bool handle(internal::null<>) {
+      using namespace fmt::internal;
+      return fallback(gmtime_s(&tm_, &time_));
+    }
+
+    bool fallback(int res) { return res == 0; }
+
+    bool fallback(internal::null<>) {
+      std::tm *tm = std::gmtime(&time_);
+      if (tm) tm_ = *tm;
+      return tm != FMT_NULL;
+    }
+  };
+  dispatcher gt(time);
+  if (gt.run())
+    return gt.tm_;
+  // Too big time values may be unsupported.
+  FMT_THROW(format_error("time_t value out of range"));
+}
+
+namespace internal {
+inline std::size_t strftime(char *str, std::size_t count, const char *format,
+                            const std::tm *time) {
+  return std::strftime(str, count, format, time);
+}
+
+inline std::size_t strftime(wchar_t *str, std::size_t count,
+                            const wchar_t *format, const std::tm *time) {
+  return std::wcsftime(str, count, format, time);
+}
+}
+
+template <typename Char>
+struct formatter<std::tm, Char> {
+  template <typename ParseContext>
+  auto parse(ParseContext &ctx) -> decltype(ctx.begin()) {
+    auto it = internal::null_terminating_iterator<Char>(ctx);
+    if (*it == ':')
+      ++it;
+    auto end = it;
+    while (*end && *end != '}')
+      ++end;
+    tm_format.reserve(end - it + 1);
+    using internal::pointer_from;
+    tm_format.append(pointer_from(it), pointer_from(end));
+    tm_format.push_back('\0');
+    return pointer_from(end);
+  }
+
+  template <typename FormatContext>
+  auto format(const std::tm &tm, FormatContext &ctx) -> decltype(ctx.out()) {
+    internal::basic_buffer<Char> &buf = internal::get_container(ctx.out());
+    std::size_t start = buf.size();
+    for (;;) {
+      std::size_t size = buf.capacity() - start;
+      std::size_t count =
+        internal::strftime(&buf[start], size, &tm_format[0], &tm);
+      if (count != 0) {
+        buf.resize(start + count);
+        break;
+      }
+      if (size >= tm_format.size() * 256) {
+        // If the buffer is 256 times larger than the format string, assume
+        // that `strftime` gives an empty result. There doesn't seem to be a
+        // better way to distinguish the two cases:
+        // https://github.com/fmtlib/fmt/issues/367
+        break;
+      }
+      const std::size_t MIN_GROWTH = 10;
+      buf.reserve(buf.capacity() + (size > MIN_GROWTH ? size : MIN_GROWTH));
+    }
+    return ctx.out();
+  }
+
+  basic_memory_buffer<Char> tm_format;
+};
+FMT_END_NAMESPACE
+
+#endif  // FMT_TIME_H_
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/src/format.cc	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,52 @@
+// Formatting library for C++
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+#include "fmt/format-inl.h"
+
+FMT_BEGIN_NAMESPACE
+namespace internal {
+// Force linking of inline functions into the library.
+std::string (*vformat_ref)(string_view, format_args) = vformat;
+std::wstring (*vformat_wref)(wstring_view, wformat_args) = vformat;
+}
+
+template struct internal::basic_data<void>;
+
+// Explicit instantiations for char.
+
+template FMT_API char internal::thousands_sep(locale_provider *lp);
+
+template void basic_fixed_buffer<char>::grow(std::size_t);
+
+template void internal::arg_map<format_context>::init(
+    const basic_format_args<format_context> &args);
+
+template FMT_API int internal::char_traits<char>::format_float(
+    char *buffer, std::size_t size, const char *format, int precision,
+    double value);
+
+template FMT_API int internal::char_traits<char>::format_float(
+    char *buffer, std::size_t size, const char *format, int precision,
+    long double value);
+
+// Explicit instantiations for wchar_t.
+
+template FMT_API wchar_t internal::thousands_sep(locale_provider *lp);
+
+template void basic_fixed_buffer<wchar_t>::grow(std::size_t);
+
+template void internal::arg_map<wformat_context>::init(
+    const basic_format_args<wformat_context> &args);
+
+template FMT_API int internal::char_traits<wchar_t>::format_float(
+    wchar_t *buffer, std::size_t size, const wchar_t *format,
+    int precision, double value);
+
+template FMT_API int internal::char_traits<wchar_t>::format_float(
+    wchar_t *buffer, std::size_t size, const wchar_t *format,
+    int precision, long double value);
+FMT_END_NAMESPACE
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/src/posix.cc	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,244 @@
+// A C++ interface to POSIX functions.
+//
+// Copyright (c) 2012 - 2016, Victor Zverovich
+// All rights reserved.
+//
+// For the license information refer to format.h.
+
+// Disable bogus MSVC warnings.
+#if !defined(_CRT_SECURE_NO_WARNINGS) && defined(_MSC_VER)
+# define _CRT_SECURE_NO_WARNINGS
+#endif
+
+#include "fmt/posix.h"
+
+#include <limits.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifndef _WIN32
+# include <unistd.h>
+#else
+# ifndef WIN32_LEAN_AND_MEAN
+#  define WIN32_LEAN_AND_MEAN
+# endif
+# include <windows.h>
+# include <io.h>
+
+# define O_CREAT _O_CREAT
+# define O_TRUNC _O_TRUNC
+
+# ifndef S_IRUSR
+#  define S_IRUSR _S_IREAD
+# endif
+
+# ifndef S_IWUSR
+#  define S_IWUSR _S_IWRITE
+# endif
+
+# ifdef __MINGW32__
+#  define _SH_DENYNO 0x40
+# endif
+
+#endif  // _WIN32
+
+#ifdef fileno
+# undef fileno
+#endif
+
+namespace {
+#ifdef _WIN32
+// Return type of read and write functions.
+typedef int RWResult;
+
+// On Windows the count argument to read and write is unsigned, so convert
+// it from size_t preventing integer overflow.
+inline unsigned convert_rwcount(std::size_t count) {
+  return count <= UINT_MAX ? static_cast<unsigned>(count) : UINT_MAX;
+}
+#else
+// Return type of read and write functions.
+typedef ssize_t RWResult;
+
+inline std::size_t convert_rwcount(std::size_t count) { return count; }
+#endif
+}
+
+FMT_BEGIN_NAMESPACE
+
+buffered_file::~buffered_file() FMT_NOEXCEPT {
+  if (file_ && FMT_SYSTEM(fclose(file_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+buffered_file::buffered_file(cstring_view filename, cstring_view mode) {
+  FMT_RETRY_VAL(file_,
+                FMT_SYSTEM(fopen(filename.c_str(), mode.c_str())), FMT_NULL);
+  if (!file_)
+    FMT_THROW(system_error(errno, "cannot open file {}", filename.c_str()));
+}
+
+void buffered_file::close() {
+  if (!file_)
+    return;
+  int result = FMT_SYSTEM(fclose(file_));
+  file_ = FMT_NULL;
+  if (result != 0)
+    FMT_THROW(system_error(errno, "cannot close file"));
+}
+
+// A macro used to prevent expansion of fileno on broken versions of MinGW.
+#define FMT_ARGS
+
+int buffered_file::fileno() const {
+  int fd = FMT_POSIX_CALL(fileno FMT_ARGS(file_));
+  if (fd == -1)
+    FMT_THROW(system_error(errno, "cannot get file descriptor"));
+  return fd;
+}
+
+file::file(cstring_view path, int oflag) {
+  int mode = S_IRUSR | S_IWUSR;
+#if defined(_WIN32) && !defined(__MINGW32__)
+  fd_ = -1;
+  FMT_POSIX_CALL(sopen_s(&fd_, path.c_str(), oflag, _SH_DENYNO, mode));
+#else
+  FMT_RETRY(fd_, FMT_POSIX_CALL(open(path.c_str(), oflag, mode)));
+#endif
+  if (fd_ == -1)
+    FMT_THROW(system_error(errno, "cannot open file {}", path.c_str()));
+}
+
+file::~file() FMT_NOEXCEPT {
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  if (fd_ != -1 && FMT_POSIX_CALL(close(fd_)) != 0)
+    report_system_error(errno, "cannot close file");
+}
+
+void file::close() {
+  if (fd_ == -1)
+    return;
+  // Don't retry close in case of EINTR!
+  // See http://linux.derkeiler.com/Mailing-Lists/Kernel/2005-09/3000.html
+  int result = FMT_POSIX_CALL(close(fd_));
+  fd_ = -1;
+  if (result != 0)
+    FMT_THROW(system_error(errno, "cannot close file"));
+}
+
+long long file::size() const {
+#ifdef _WIN32
+  // Use GetFileSize instead of GetFileSizeEx for the case when _WIN32_WINNT
+  // is less than 0x0500 as is the case with some default MinGW builds.
+  // Both functions support large file sizes.
+  DWORD size_upper = 0;
+  HANDLE handle = reinterpret_cast<HANDLE>(_get_osfhandle(fd_));
+  DWORD size_lower = FMT_SYSTEM(GetFileSize(handle, &size_upper));
+  if (size_lower == INVALID_FILE_SIZE) {
+    DWORD error = GetLastError();
+    if (error != NO_ERROR)
+      FMT_THROW(windows_error(GetLastError(), "cannot get file size"));
+  }
+  unsigned long long long_size = size_upper;
+  return (long_size << sizeof(DWORD) * CHAR_BIT) | size_lower;
+#else
+  typedef struct stat Stat;
+  Stat file_stat = Stat();
+  if (FMT_POSIX_CALL(fstat(fd_, &file_stat)) == -1)
+    FMT_THROW(system_error(errno, "cannot get file attributes"));
+  static_assert(sizeof(long long) >= sizeof(file_stat.st_size),
+      "return type of file::size is not large enough");
+  return file_stat.st_size;
+#endif
+}
+
+std::size_t file::read(void *buffer, std::size_t count) {
+  RWResult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(read(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, "cannot read from file"));
+  return internal::to_unsigned(result);
+}
+
+std::size_t file::write(const void *buffer, std::size_t count) {
+  RWResult result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(write(fd_, buffer, convert_rwcount(count))));
+  if (result < 0)
+    FMT_THROW(system_error(errno, "cannot write to file"));
+  return internal::to_unsigned(result);
+}
+
+file file::dup(int fd) {
+  // Don't retry as dup doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009695399/functions/dup.html
+  int new_fd = FMT_POSIX_CALL(dup(fd));
+  if (new_fd == -1)
+    FMT_THROW(system_error(errno, "cannot duplicate file descriptor {}", fd));
+  return file(new_fd);
+}
+
+void file::dup2(int fd) {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1) {
+    FMT_THROW(system_error(errno,
+      "cannot duplicate file descriptor {} to {}", fd_, fd));
+  }
+}
+
+void file::dup2(int fd, error_code &ec) FMT_NOEXCEPT {
+  int result = 0;
+  FMT_RETRY(result, FMT_POSIX_CALL(dup2(fd_, fd)));
+  if (result == -1)
+    ec = error_code(errno);
+}
+
+void file::pipe(file &read_end, file &write_end) {
+  // Close the descriptors first to make sure that assignments don't throw
+  // and there are no leaks.
+  read_end.close();
+  write_end.close();
+  int fds[2] = {};
+#ifdef _WIN32
+  // Make the default pipe capacity same as on Linux 2.6.11+.
+  enum { DEFAULT_CAPACITY = 65536 };
+  int result = FMT_POSIX_CALL(pipe(fds, DEFAULT_CAPACITY, _O_BINARY));
+#else
+  // Don't retry as the pipe function doesn't return EINTR.
+  // http://pubs.opengroup.org/onlinepubs/009696799/functions/pipe.html
+  int result = FMT_POSIX_CALL(pipe(fds));
+#endif
+  if (result != 0)
+    FMT_THROW(system_error(errno, "cannot create pipe"));
+  // The following assignments don't throw because read_fd and write_fd
+  // are closed.
+  read_end = file(fds[0]);
+  write_end = file(fds[1]);
+}
+
+buffered_file file::fdopen(const char *mode) {
+  // Don't retry as fdopen doesn't return EINTR.
+  FILE *f = FMT_POSIX_CALL(fdopen(fd_, mode));
+  if (!f)
+    FMT_THROW(system_error(errno,
+                           "cannot associate stream with file descriptor"));
+  buffered_file bf(f);
+  fd_ = -1;
+  return bf;
+}
+
+long getpagesize() {
+#ifdef _WIN32
+  SYSTEM_INFO si;
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+#else
+  long size = FMT_POSIX_CALL(sysconf(_SC_PAGESIZE));
+  if (size < 0)
+    FMT_THROW(system_error(errno, "cannot get memory page size"));
+  return size;
+#endif
+}
+FMT_END_NAMESPACE
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fmt/support/cmake/cxx14.cmake	Fri Jul 13 13:15:12 2018 +0200
@@ -0,0 +1,97 @@
+# C++14 feature support detection
+
+include(CheckCXXSourceCompiles)
+include(CheckCXXCompilerFlag)
+
+if (NOT CMAKE_CXX_STANDARD)
+  set(CMAKE_CXX_STANDARD 11)
+endif()
+message(STATUS "CXX_STANDARD: ${CMAKE_CXX_STANDARD}")
+
+if (CMAKE_CXX_STANDARD EQUAL 20)
+  check_cxx_compiler_flag(-std=c++20 has_std_20_flag)
+  check_cxx_compiler_flag(-std=c++2a has_std_2a_flag)
+
+  if (has_std_20_flag)
+    set(CXX_STANDARD_FLAG -std=c++20)
+  elseif (has_std_2a_flag)
+    set(CXX_STANDARD_FLAG -std=c++2a)
+  endif ()
+elseif (CMAKE_CXX_STANDARD EQUAL 17)
+  check_cxx_compiler_flag(-std=c++17 has_std_17_flag)
+  check_cxx_compiler_flag(-std=c++1z has_std_1z_flag)
+
+  if (has_std_17_flag)
+    set(CXX_STANDARD_FLAG -std=c++17)
+  elseif (has_std_1z_flag)
+    set(CXX_STANDARD_FLAG -std=c++1z)
+  endif ()
+elseif (CMAKE_CXX_STANDARD EQUAL 14)
+  check_cxx_compiler_flag(-std=c++14 has_std_14_flag)
+  check_cxx_compiler_flag(-std=c++1y has_std_1y_flag)
+
+  if (has_std_14_flag)
+    set(CXX_STANDARD_FLAG -std=c++14)
+  elseif (has_std_1y_flag)
+    set(CXX_STANDARD_FLAG -std=c++1y)
+  endif ()
+elseif (CMAKE_CXX_STANDARD EQUAL 11)
+  check_cxx_compiler_flag(-std=c++11 has_std_11_flag)
+  check_cxx_compiler_flag(-std=c++0x has_std_0x_flag)
+
+  if (has_std_11_flag)
+    set(CXX_STANDARD_FLAG -std=c++11)
+  elseif (has_std_0x_flag)
+    set(CXX_STANDARD_FLAG -std=c++0x)
+  endif ()
+endif ()
+
+set(CMAKE_REQUIRED_FLAGS ${CXX_STANDARD_FLAG})
+
+# Check if variadic templates are working and not affected by GCC bug 39653:
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=39653
+check_cxx_source_compiles("
+  template <class T, class ...Types>
+  struct S { typedef typename S<Types...>::type type; };
+  int main() {}" SUPPORTS_VARIADIC_TEMPLATES)
+if (NOT SUPPORTS_VARIADIC_TEMPLATES)
+  set (SUPPORTS_VARIADIC_TEMPLATES OFF)
+endif ()
+
+# Check if initializer lists are supported.
+check_cxx_source_compiles("
+  #include <initializer_list>
+  int main() {}" SUPPORTS_INITIALIZER_LIST)
+if (NOT SUPPORTS_INITIALIZER_LIST)
+  set (SUPPORTS_INITIALIZER_LIST OFF)
+endif ()
+
+# Check if enum bases are available
+check_cxx_source_compiles("
+  enum C : char {A};
+  int main() {}"
+  SUPPORTS_ENUM_BASE)
+if (NOT SUPPORTS_ENUM_BASE)
+  set (SUPPORTS_ENUM_BASE OFF)
+endif ()
+
+# Check if type traits are available
+check_cxx_source_compiles("
+  #include <type_traits>
+  class C { void operator=(const C&); };
+  int main() { static_assert(!std::is_copy_assignable<C>::value, \"\"); }"
+  SUPPORTS_TYPE_TRAITS)
+if (NOT SUPPORTS_TYPE_TRAITS)
+  set (SUPPORTS_TYPE_TRAITS OFF)
+endif ()
+
+# Check if user-defined literals are available
+check_cxx_source_compiles("
+  void operator\"\" _udl(long double);
+  int main() {}"
+  SUPPORTS_USER_DEFINED_LITERALS)
+if (NOT SUPPORTS_USER_DEFINED_LITERALS)
+  set (SUPPORTS_USER_DEFINED_LITERALS OFF)
+endif ()
+
+set(CMAKE_REQUIRED_FLAGS )
--- a/tests/fmt/main.cpp	Fri Jul 13 12:57:10 2018 +0200
+++ b/tests/fmt/main.cpp	Fri Jul 13 13:15:12 2018 +0200
@@ -16,7 +16,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#include <format.h>
+#include <fmt/format.h>
 
 int main()
 {