Added cppformat files

include/spdlog/details/format.cc

+/*
+Formatting library for C++
+
+Copyright (c) 2012 - 2014, 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.
+*/
+
+// Disable useless MSVC warnings.
+#undef _CRT_SECURE_NO_WARNINGS
+#define _CRT_SECURE_NO_WARNINGS
+#undef _SCL_SECURE_NO_WARNINGS
+#define _SCL_SECURE_NO_WARNINGS
+
+#include "format.h"
+
+#include <string.h>
+
+#include <cctype>
+#include <cerrno>
+#include <climits>
+#include <cmath>
+#include <cstdarg>
+
+#ifdef _WIN32
+# define WIN32_LEAN_AND_MEAN
+# ifdef __MINGW32__
+#  include <cstring>
+# endif
+# include <windows.h>
+# undef ERROR
+#endif
+
+using fmt::LongLong;
+using fmt::ULongLong;
+using fmt::internal::Arg;
+
+// Check if exceptions are disabled.
+#if __GNUC__ && !__EXCEPTIONS
+# define FMT_EXCEPTIONS 0
+#endif
+#if _MSC_VER && !_HAS_EXCEPTIONS
+# define FMT_EXCEPTIONS 0
+#endif
+#ifndef FMT_EXCEPTIONS
+# define FMT_EXCEPTIONS 1
+#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
+
+#ifndef FMT_THROW
+# if FMT_EXCEPTIONS
+#  define FMT_THROW(x) throw x
+# else
+#  define FMT_THROW(x) assert(false)
+# endif
+#endif
+
+#ifdef FMT_HEADER_ONLY
+# define FMT_FUNC inline
+#else
+# define FMT_FUNC
+#endif
+
+#if _MSC_VER
+# pragma warning(push)
+# pragma warning(disable: 4127)  // conditional expression is constant
+#endif
+
+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
+
+// 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;
+    }
+};
+
+template <>
+struct IntChecker<true> {
+    template <typename T>
+    static bool fits_in_int(T value) {
+        return value >= INT_MIN && value <= INT_MAX;
+    }
+};
+
+const char RESET_COLOR[] = "\x1b[0m";
+
+typedef void(*FormatFunc)(fmt::Writer &, int, fmt::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(true) {
+    assert(buffer != 0 && buffer_size != 0);
+    int result = 0;
+#ifdef _GNU_SOURCE
+    char *message = strerror_r(error_code, buffer, buffer_size);
+    // If the buffer is full then the message is probably truncated.
+    if (message == buffer && strlen(buffer) == buffer_size - 1)
+        result = ERANGE;
+    buffer = message;
+#elif __MINGW32__
+    errno = 0;
+    (void)buffer_size;
+    buffer = strerror(error_code);
+    result = errno;
+#elif _WIN32
+    result = strerror_s(buffer, buffer_size, error_code);
+    // If the buffer is full then the message is probably truncated.
+    if (result == 0 && std::strlen(buffer) == buffer_size - 1)
+        result = ERANGE;
+#else
+    result = strerror_r(error_code, buffer, buffer_size);
+    if (result == -1)
+        result = errno;  // glibc versions before 2.13 return result in errno.
+#endif
+    return result;
+}
+
+void format_error_code(fmt::Writer &out, int error_code,
+                       fmt::StringRef message) FMT_NOEXCEPT(true) {
+    // 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[] = "error ";
+    fmt::internal::IntTraits<int>::MainType ec_value = error_code;
+    // Subtract 2 to account for terminating null characters in SEP and ERROR.
+    std::size_t error_code_size =
+        sizeof(SEP) + sizeof(ERROR) + fmt::internal::count_digits(ec_value) - 2;
+    if (message.size() <= fmt::internal::INLINE_BUFFER_SIZE - error_code_size)
+        out << message << SEP;
+    out << ERROR << error_code;
+    assert(out.size() <= fmt::internal::INLINE_BUFFER_SIZE);
+}
+
+void report_error(FormatFunc func,
+                  int error_code, fmt::StringRef message) FMT_NOEXCEPT(true) {
+    fmt::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 fmt::internal::ArgVisitor<IsZeroInt, bool> {
+public:
+    template <typename T>
+    bool visit_any_int(T value) {
+        return value == 0;
+    }
+};
+
+// 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>
+int 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 = UINT_MAX;
+            break;
+        }
+        value = new_value;
+    } while ('0' <= *s && *s <= '9');
+    if (value > INT_MAX)
+        FMT_THROW(fmt::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(fmt::FormatError(fmt::format(
+                                       "format specifier '{}' requires signed argument", sign)));
+    }
+    ++s;
+}
+
+// Checks if an argument is a valid printf width specifier and sets
+// left alignment if it is negative.
+class WidthHandler : public fmt::internal::ArgVisitor<WidthHandler, unsigned> {
+private:
+    fmt::FormatSpec &spec_;
+
+public:
+    explicit WidthHandler(fmt::FormatSpec &spec) : spec_(spec) {}
+
+    unsigned visit_unhandled_arg() {
+        FMT_THROW(fmt::FormatError("width is not integer"));
+        return 0;
+    }
+
+    template <typename T>
+    unsigned visit_any_int(T value) {
+        typedef typename fmt::internal::IntTraits<T>::MainType UnsignedType;
+        UnsignedType width = value;
+        if (fmt::internal::is_negative(value)) {
+            spec_.align_ = fmt::ALIGN_LEFT;
+            width = 0 - width;
+        }
+        if (width > INT_MAX)
+            FMT_THROW(fmt::FormatError("number is too big"));
+        return static_cast<unsigned>(width);
+    }
+};
+
+class PrecisionHandler :
+    public fmt::internal::ArgVisitor<PrecisionHandler, int> {
+public:
+    unsigned visit_unhandled_arg() {
+        FMT_THROW(fmt::FormatError("precision is not integer"));
+        return 0;
+    }
+
+    template <typename T>
+    int visit_any_int(T value) {
+        if (!IntChecker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
+            FMT_THROW(fmt::FormatError("number is too big"));
+        return static_cast<int>(value);
+    }
+};
+
+// Converts an integer argument to an integral type T for printf.
+template <typename T>
+class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
+private:
+    fmt::internal::Arg &arg_;
+    wchar_t type_;
+
+public:
+    ArgConverter(fmt::internal::Arg &arg, wchar_t type)
+        : arg_(arg), type_(type) {}
+
+    template <typename U>
+    void visit_any_int(U value) {
+        bool is_signed = type_ == 'd' || type_ == 'i';
+        using fmt::internal::Arg;
+        if (sizeof(T) <= sizeof(int)) {
+            // Extra casts are used to silence warnings.
+            if (is_signed) {
+                arg_.type = Arg::INT;
+                arg_.int_value = static_cast<int>(static_cast<T>(value));
+            }
+            else {
+                arg_.type = Arg::UINT;
+                arg_.uint_value = static_cast<unsigned>(
+                                      static_cast<typename fmt::internal::MakeUnsigned<T>::Type>(value));
+            }
+        }
+        else {
+            if (is_signed) {
+                arg_.type = Arg::LONG_LONG;
+                arg_.long_long_value =
+                    static_cast<typename fmt::internal::MakeUnsigned<U>::Type>(value);
+            }
+            else {
+                arg_.type = Arg::ULONG_LONG;
+                arg_.ulong_long_value =
+                    static_cast<typename fmt::internal::MakeUnsigned<U>::Type>(value);
+            }
+        }
+    }
+};
+
+// Converts an integer argument to char for printf.
+class CharConverter : public fmt::internal::ArgVisitor<CharConverter, void> {
+private:
+    fmt::internal::Arg &arg_;
+
+public:
+    explicit CharConverter(fmt::internal::Arg &arg) : arg_(arg) {}
+
+    template <typename T>
+    void visit_any_int(T value) {
+        arg_.type = Arg::CHAR;
+        arg_.int_value = static_cast<char>(value);
+    }
+};
+
+// This function template is used to prevent compile errors when handling
+// incompatible string arguments, e.g. handling a wide string in a narrow
+// string formatter.
+template <typename Char>
+Arg::StringValue<Char> ignore_incompatible_str(Arg::StringValue<wchar_t>);
+
+template <>
+inline Arg::StringValue<char> ignore_incompatible_str(
+    Arg::StringValue<wchar_t>) {
+    return Arg::StringValue<char>();
+}
+
+template <>
+inline Arg::StringValue<wchar_t> ignore_incompatible_str(
+    Arg::StringValue<wchar_t> s) {
+    return s;
+}
+}  // namespace
+
+FMT_FUNC void fmt::SystemError::init(
+    int error_code, StringRef format_str, ArgList args) {
+    error_code_ = error_code;
+    MemoryWriter w;
+    internal::format_system_error(w, error_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 ?
+               swprintf(buffer, size, format, value) :
+               swprintf(buffer, size, format, precision, value);
+    }
+    return precision < 0 ?
+           swprintf(buffer, size, format, width, value) :
+           swprintf(buffer, size, format, width, precision, value);
+}
+
+const char fmt::internal::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
+
+const uint32_t fmt::internal::POWERS_OF_10_32[] = { 0, FMT_POWERS_OF_10(1) };
+const uint64_t fmt::internal::POWERS_OF_10_64[] = {
+    0,
+    FMT_POWERS_OF_10(1),
+    FMT_POWERS_OF_10(ULongLong(1000000000)),
+    // Multiply several constants instead of using a single long long constant
+    // to avoid warnings about C++98 not supporting long long.
+    ULongLong(1000000000) * ULongLong(1000000000) * 10
+};
+
+FMT_FUNC void fmt::internal::report_unknown_type(char code, const char *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)));
+}
+
+#ifdef _WIN32
+
+fmt::internal::UTF8ToUTF16::UTF8ToUTF16(fmt::StringRef s) {
+    int length = MultiByteToWideChar(
+                     CP_UTF8, MB_ERR_INVALID_CHARS, s.c_str(), -1, 0, 0);
+    static const char ERROR[] = "cannot convert string from UTF-8 to UTF-16";
+    if (length == 0)
+        FMT_THROW(WindowsError(GetLastError(), ERROR));
+    buffer_.resize(length);
+    length = MultiByteToWideChar(
+                 CP_UTF8, MB_ERR_INVALID_CHARS, s.c_str(), -1, &buffer_[0], length);
+    if (length == 0)
+        FMT_THROW(WindowsError(GetLastError(), ERROR));
+}
+
+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"));
+    }
+}
+
+int fmt::internal::UTF16ToUTF8::convert(fmt::WStringRef s) {
+    int length = WideCharToMultiByte(CP_UTF8, 0, s.c_str(), -1, 0, 0, 0, 0);
+    if (length == 0)
+        return GetLastError();
+    buffer_.resize(length);
+    length = WideCharToMultiByte(
+                 CP_UTF8, 0, s.c_str(), -1, &buffer_[0], length, 0, 0);
+    if (length == 0)
+        return GetLastError();
+    return 0;
+}
+
+void fmt::WindowsError::init(
+    int error_code, StringRef format_str, ArgList args) {
+    error_code_ = error_code;
+    MemoryWriter w;
+    internal::format_windows_error(w, error_code, format(format_str, args));
+    std::runtime_error &base = *this;
+    base = std::runtime_error(w.str());
+}
+
+#endif
+
+FMT_FUNC void fmt::internal::format_system_error(
+    fmt::Writer &out, int error_code,
+    fmt::StringRef message) FMT_NOEXCEPT(true) {
+    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(...) {}
+    format_error_code(out, error_code, message);
+}
+
+#ifdef _WIN32
+void fmt::internal::format_windows_error(
+    fmt::Writer &out, int error_code,
+    fmt::StringRef message) FMT_NOEXCEPT(true) {
+    class String {
+    private:
+        LPWSTR str_;
+
+    public:
+        String() : str_() {}
+        ~String() {
+            LocalFree(str_);
+        }
+        LPWSTR *ptr() {
+            return &str_;
+        }
+        LPCWSTR c_str() const {
+            return str_;
+        }
+    };
+    FMT_TRY {
+        String system_message;
+        if (FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+        FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, 0,
+        error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+        reinterpret_cast<LPWSTR>(system_message.ptr()), 0, 0)) {
+            UTF16ToUTF8 utf8_message;
+            if (utf8_message.convert(system_message.c_str()) == ERROR_SUCCESS) {
+                out << message << ": " << utf8_message;
+                return;
+            }
+        }
+    } FMT_CATCH(...) {}
+    format_error_code(out, error_code, message);
+}
+#endif
+
+// An argument formatter.
+template <typename Char>
+class fmt::internal::ArgFormatter :
+    public fmt::internal::ArgVisitor<fmt::internal::ArgFormatter<Char>, void> {
+private:
+    fmt::BasicFormatter<Char> &formatter_;
+    fmt::BasicWriter<Char> &writer_;
+    fmt::FormatSpec &spec_;
+    const Char *format_;
+
+public:
+    ArgFormatter(
+        fmt::BasicFormatter<Char> &f, fmt::FormatSpec &s, const Char *fmt)
+        : formatter_(f), writer_(f.writer()), spec_(s), format_(fmt) {}
+
+    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_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 fmt::BasicWriter<Char>::CharPtr CharPtr;
+        CharPtr out = CharPtr();
+        if (spec_.width_ > 1) {
+            Char fill = static_cast<Char>(spec_.fill());
+            out = writer_.grow_buffer(spec_.width_);
+            if (spec_.align_ == fmt::ALIGN_RIGHT) {
+                std::fill_n(out, spec_.width_ - 1, fill);
+                out += spec_.width_ - 1;
+            }
+            else if (spec_.align_ == fmt::ALIGN_CENTER) {
+                out = writer_.fill_padding(out, spec_.width_, 1, fill);
+            }
+            else {
+                std::fill_n(out + 1, spec_.width_ - 1, fill);
+            }
+        }
+        else {
+            out = writer_.grow_buffer(1);
+        }
+        *out = static_cast<Char>(value);
+    }
+
+    void visit_string(Arg::StringValue<char> value) {
+        writer_.write_str(value, spec_);
+    }
+    void visit_wstring(Arg::StringValue<wchar_t> value) {
+        writer_.write_str(ignore_incompatible_str<Char>(value), spec_);
+    }
+
+    void visit_pointer(const void *value) {
+        if (spec_.type_ && spec_.type_ != 'p')
+            fmt::internal::report_unknown_type(spec_.type_, "pointer");
+        spec_.flags_ = fmt::HASH_FLAG;
+        spec_.type_ = 'x';
+        writer_.write_int(reinterpret_cast<uintptr_t>(value), spec_);
+    }
+
+    void visit_custom(Arg::CustomValue c) {
+        c.format(&formatter_, c.value, &format_);
+    }
+};
+
+template <typename Char>
+template <typename StrChar>
+void fmt::BasicWriter<Char>::write_str(
+    const Arg::StringValue<StrChar> &str, 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 *s = str.value;
+    std::size_t size = str.size;
+    if (size == 0) {
+        if (!s)
+            FMT_THROW(FormatError("string pointer is null"));
+        if (*s)
+            size = std::char_traits<StrChar>::length(s);
+    }
+    write_str(s, size, spec);
+}
+
+template <typename Char>
+inline Arg fmt::BasicFormatter<Char>::parse_arg_index(const Char *&s) {
+    const char *error = 0;
+    Arg arg = *s < '0' || *s > '9' ?
+              next_arg(error) : get_arg(parse_nonnegative_int(s), error);
+    if (error) {
+        FMT_THROW(FormatError(
+                      *s != '}' && *s != ':' ? "invalid format string" : error));
+    }
+    return arg;
+}
+
+FMT_FUNC Arg fmt::internal::FormatterBase::do_get_arg(
+    unsigned arg_index, const char *&error) {
+    Arg arg = args_[arg_index];
+    if (arg.type == Arg::NONE)
+        error = "argument index out of range";
+    return arg;
+}
+
+inline Arg fmt::internal::FormatterBase::next_arg(const char *&error) {
+    if (next_arg_index_ >= 0)
+        return do_get_arg(next_arg_index_++, error);
+    error = "cannot switch from manual to automatic argument indexing";
+    return Arg();
+}
+
+inline Arg fmt::internal::FormatterBase::get_arg(
+    unsigned arg_index, const char *&error) {
+    if (next_arg_index_ <= 0) {
+        next_arg_index_ = -1;
+        return do_get_arg(arg_index, error);
+    }
+    error = "cannot switch from automatic to manual argument indexing";
+    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) {
+    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, BasicStringRef<Char> format,
+    const ArgList &args) {
+    const Char *start = format.c_str();
+    set_args(args);
+    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_ = 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_ &= ~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<size_t>(arg, *s).visit(arg);
+            break;
+        case 't':
+            ArgConverter<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<int>(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.
+        switch (arg.type) {
+        case Arg::INT:
+            writer.write_int(arg.int_value, spec);
+            break;
+        case Arg::UINT:
+            writer.write_int(arg.uint_value, spec);
+            break;
+        case Arg::LONG_LONG:
+            writer.write_int(arg.long_long_value, spec);
+            break;
+        case Arg::ULONG_LONG:
+            writer.write_int(arg.ulong_long_value, spec);
+            break;
+        case Arg::CHAR: {
+            if (spec.type_ && spec.type_ != 'c')
+                writer.write_int(arg.int_value, spec);
+            typedef typename BasicWriter<Char>::CharPtr CharPtr;
+            CharPtr out = CharPtr();
+            if (spec.width_ > 1) {
+                Char fill = ' ';
+                out = writer.grow_buffer(spec.width_);
+                if (spec.align_ != ALIGN_LEFT) {
+                    std::fill_n(out, spec.width_ - 1, fill);
+                    out += spec.width_ - 1;
+                }
+                else {
+                    std::fill_n(out + 1, spec.width_ - 1, fill);
+                }
+            }
+            else {
+                out = writer.grow_buffer(1);
+            }
+            *out = static_cast<Char>(arg.int_value);
+            break;
+        }
+        case Arg::DOUBLE:
+            writer.write_double(arg.double_value, spec);
+            break;
+        case Arg::LONG_DOUBLE:
+            writer.write_double(arg.long_double_value, spec);
+            break;
+        case Arg::CSTRING:
+            arg.string.size = 0;
+            writer.write_str(arg.string, spec);
+            break;
+        case Arg::STRING:
+            writer.write_str(arg.string, spec);
+            break;
+        case Arg::WSTRING:
+            writer.write_str(ignore_incompatible_str<Char>(arg.wstring), spec);
+            break;
+        case Arg::POINTER:
+            if (spec.type_ && spec.type_ != 'p')
+                internal::report_unknown_type(spec.type_, "pointer");
+            spec.flags_ = HASH_FLAG;
+            spec.type_ = 'x';
+            writer.write_int(reinterpret_cast<uintptr_t>(arg.pointer), spec);
+            break;
+        case Arg::CUSTOM: {
+            if (spec.type_)
+                internal::report_unknown_type(spec.type_, "object");
+            const void *s = "s";
+            arg.custom.format(&writer, arg.custom.value, &s);
+            break;
+        }
+        default:
+            assert(false);
+            break;
+        }
+    }
+    write(writer, start, s);
+}
+
+template <typename Char>
+const Char *fmt::BasicFormatter<Char>::format(
+    const Char *&format_str, const Arg &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 width and zero flag.
+        if ('0' <= *s && *s <= '9') {
+            if (*s == '0') {
+                require_numeric_argument(arg, '0');
+                spec.align_ = ALIGN_NUMERIC;
+                spec.fill_ = '0';
+            }
+            // Zero may be parsed again as a part of the width, but it is simpler
+            // and more efficient than checking if the next char is a digit.
+            spec.width_ = parse_nonnegative_int(s);
+        }
+
+        // Parse precision.
+        if (*s == '.') {
+            ++s;
+            spec.precision_ = 0;
+            if ('0' <= *s && *s <= '9') {
+                spec.precision_ = parse_nonnegative_int(s);
+            }
+            else if (*s == '{') {
+                ++s;
+                const Arg &precision_arg = 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 > 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::DOUBLE && arg.type != Arg::LONG_DOUBLE) {
+                FMT_THROW(FormatError(
+                              "precision specifier requires floating-point argument"));
+            }
+        }
+
+        // Parse type.
+        if (*s != '}' && *s)
+            spec.type_ = static_cast<char>(*s++);
+    }
+
+    if (*s++ != '}')
+        FMT_THROW(FormatError("missing '}' in format string"));
+    start_ = s;
+
+    // Format argument.
+    internal::ArgFormatter<Char>(*this, spec, s - 1).visit(arg);
+    return s;
+}
+
+template <typename Char>
+void fmt::BasicFormatter<Char>::format(
+    BasicStringRef<Char> format_str, const ArgList &args) {
+    const Char *s = start_ = format_str.c_str();
+    set_args(args);
+    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);
+        Arg arg = parse_arg_index(s);
+        s = format(s, arg);
+    }
+    write(writer_, start_, s);
+}
+
+FMT_FUNC void fmt::report_system_error(
+    int error_code, fmt::StringRef message) FMT_NOEXCEPT(true) {
+    report_error(internal::format_system_error, error_code, message);
+}
+
+#ifdef _WIN32
+void fmt::report_windows_error(
+    int error_code, fmt::StringRef message) FMT_NOEXCEPT(true) {
+    report_error(internal::format_windows_error, error_code, message);
+}
+#endif
+
+FMT_FUNC void fmt::print(std::FILE *f, StringRef format_str, ArgList args) {
+    MemoryWriter w;
+    w.write(format_str, args);
+    std::fwrite(w.data(), 1, w.size(), f);
+}
+
+FMT_FUNC void fmt::print(StringRef format_str, ArgList args) {
+    print(stdout, format_str, args);
+}
+
+FMT_FUNC void fmt::print(std::ostream &os, StringRef format_str, ArgList args) {
+    MemoryWriter w;
+    w.write(format_str, args);
+    os.write(w.data(), w.size());
+}
+
+FMT_FUNC void fmt::print_colored(Color c, StringRef format, ArgList args) {
+    char escape[] = "\x1b[30m";
+    escape[3] = '0' + static_cast<char>(c);
+    std::fputs(escape, stdout);
+    print(format, args);
+    std::fputs(RESET_COLOR, stdout);
+}
+
+FMT_FUNC int fmt::fprintf(std::FILE *f, StringRef 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);
+}
+
+// Explicit instantiations for char.
+
+template const char *fmt::BasicFormatter<char>::format(
+    const char *&format_str, const fmt::internal::Arg &arg);
+
+template void fmt::BasicFormatter<char>::format(
+    BasicStringRef<char> format, const ArgList &args);
+
+template void fmt::internal::PrintfFormatter<char>::format(
+    BasicWriter<char> &writer, BasicStringRef<char> format, const ArgList &args);
+
+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 const wchar_t *fmt::BasicFormatter<wchar_t>::format(
+    const wchar_t *&format_str, const fmt::internal::Arg &arg);
+
+template void fmt::BasicFormatter<wchar_t>::format(
+    BasicStringRef<wchar_t> format, const ArgList &args);
+
+template void fmt::internal::PrintfFormatter<wchar_t>::format(
+    BasicWriter<wchar_t> &writer, BasicStringRef<wchar_t> format,
+    const ArgList &args);
+
+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);
+
+#if _MSC_VER
+# pragma warning(pop)
+#endif

include/spdlog/details/format.h

+/*
+Formatting library for C++
+
+Copyright (c) 2012 - 2014, 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 <stdint.h>
+
+#include <cassert>
+#include <cmath>
+#include <cstddef>  // for std::ptrdiff_t
+#include <cstdio>
+#include <algorithm>
+#include <limits>
+#include <stdexcept>
+#include <string>
+#include <sstream>
+
+#if _SECURE_SCL
+# include <iterator>
+#endif
+
+#ifdef __GNUC__
+# define FMT_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+# define FMT_GCC_EXTENSION __extension__
+// Disable warning about "long long" which is sometimes reported even
+// when using __extension__.
+# if FMT_GCC_VERSION >= 406
+#  pragma GCC diagnostic push
+#  pragma GCC diagnostic ignored "-Wlong-long"
+# endif
+#else
+# define FMT_GCC_EXTENSION
+#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
+
+#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 && __cplusplus >= 201103) || _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 && __cplusplus >= 201103) || _MSC_VER >= 1600)
+# endif
+#endif
+
+#if FMT_USE_RVALUE_REFERENCES
+# include <utility>  // for std::move
+#endif
+
+// Define FMT_USE_NOEXCEPT to make C++ Format use noexcept (C++11 feature).
+#if FMT_USE_NOEXCEPT || FMT_HAS_FEATURE(cxx_noexcept) || \
+  (FMT_GCC_VERSION >= 408 && __cplusplus >= 201103)
+# define FMT_NOEXCEPT(expr) noexcept(expr)
+#else
+# define FMT_NOEXCEPT(expr)
+#endif
+
+// A macro to disallow the copy constructor and operator= functions
+// This should be used in the private: declarations for a class
+#define FMT_DISALLOW_COPY_AND_ASSIGN(TypeName) \
+  TypeName(const TypeName&); \
+  void operator=(const TypeName&)
+
+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 BasicFormatter;
+
+template <typename Char, typename T>
+void format(BasicFormatter<Char> &f, const Char *&format_str, const T &value);
+
+/**
+\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, 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) {}
+
+    /**
+    Constructs a string reference object from a C string computing
+    the size with ``std::char_traits<Char>::length``.
+    */
+    BasicStringRef(const Char *s)
+        : data_(s), size_(std::char_traits<Char>::length(s)) {}
+
+    /**
+    Constructs a string reference from an `std::string` object.
+    */
+    BasicStringRef(const std::basic_string<Char> &s)
+        : data_(s.c_str()), size_(s.size()) {}
+
+    /**
+    Converts a string reference to an `std::string` object.
+    */
+    operator std::basic_string<Char>() const {
+        return std::basic_string<Char>(data_, size());
+    }
+
+    /**
+    Returns the pointer to a C string.
+    */
+    const Char *c_str() const {
+        return data_;
+    }
+
+    /**
+    Returns the string size.
+    */
+    std::size_t size() const {
+        return size_;
+    }
+
+    friend bool operator==(BasicStringRef lhs, BasicStringRef rhs) {
+        return lhs.data_ == rhs.data_;
+    }
+    friend bool operator!=(BasicStringRef lhs, BasicStringRef rhs) {
+        return lhs.data_ != rhs.data_;
+    }
+};
+
+typedef BasicStringRef<char> StringRef;
+typedef BasicStringRef<wchar_t> WStringRef;
+
+/**
+A formatting error such as invalid format string.
+*/
+class FormatError : public std::runtime_error {
+public:
+    explicit FormatError(StringRef message)
+        : std::runtime_error(message.c_str()) {}
+};
+
+namespace internal {
+
+// The number of characters to store in the MemoryBuffer object itself
+// to avoid dynamic memory allocation.
+enum { INLINE_BUFFER_SIZE = 500 };
+
+#if _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
+
+// A buffer for POD types. It supports a subset of std::vector's operations.
+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) {}
+
+    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 are not initialized.
+    void resize(std::size_t new_size) {
+        if (new_size > capacity_)
+            grow(new_size);
+        size_ = new_size;
+    }
+
+    // Reserves space to store at least capacity elements.
+    void reserve(std::size_t capacity) {
+        if (capacity > capacity_)
+            grow(capacity);
+    }
+
+    void clear() FMT_NOEXCEPT(true) {
+        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.
+    void append(const T *begin, const T *end);
+
+    T &operator[](std::size_t index) {
+        return ptr_[index];
+    }
+    const T &operator[](std::size_t index) const {
+        return ptr_[index];
+    }
+};
+
+template <typename T>
+void Buffer<T>::append(const T *begin, const T *end) {
+    std::ptrdiff_t num_elements = end - begin;
+    if (size_ + num_elements > capacity_)
+        grow(size_ + num_elements);
+    std::copy(begin, end, make_ptr(ptr_, capacity_) + size_);
+    size_ += num_elements;
+}
+
+// A memory buffer for POD 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];
+
+    // Free memory allocated by the buffer.
+    void free() {
+        if (this->ptr_ != data_) this->deallocate(this->ptr_, this->capacity_);
+    }
+
+protected:
+    void grow(std::size_t size);
+
+public:
+    explicit MemoryBuffer(const Allocator &alloc = Allocator())
+        : Allocator(alloc), Buffer<T>(data_, SIZE) {}
+    ~MemoryBuffer() {
+        free();
+    }
+
+#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::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 freeing.
+            other.ptr_ = other.data_;
+        }
+    }
+
+public:
+    MemoryBuffer(MemoryBuffer &&other) {
+        move(other);
+    }
+
+    MemoryBuffer &operator=(MemoryBuffer &&other) {
+        assert(this != &other);
+        free();
+        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 =
+        (std::max)(size, this->capacity_ + this->capacity_ / 2);
+    T *new_ptr = this->allocate(new_capacity);
+    // The following code doesn't throw, so the raw pointer above doesn't leak.
+    std::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_)
+        this->deallocate(old_ptr, old_capacity);
+}
+
+#ifndef _MSC_VER
+// Portable version of signbit.
+inline int getsign(double x) {
+    // When compiled in C++11 mode signbit is no longer a macro but a function
+    // defined in namespace std and the macro is undefined.
+# ifdef signbit
+    return signbit(x);
+# else
+    return std::signbit(x);
+# endif
+}
+
+// Portable version of isinf.
+# ifdef isinf
+inline int isinfinity(double x) {
+    return isinf(x);
+}
+inline int isinfinity(long double x) {
+    return isinf(x);
+}
+# else
+inline int isinfinity(double x) {
+    return std::isinf(x);
+}
+inline int isinfinity(long double x) {
+    return std::isinf(x);
+}
+# endif
+#else
+inline int getsign(double value) {
+    if (value < 0) return 1;
+    if (value == value) return 0;
+    int dec = 0, sign = 0;
+    char buffer[2];  // The buffer size must be >= 2 or _ecvt_s will fail.
+    _ecvt_s(buffer, sizeof(buffer), value, 0, &dec, &sign);
+    return sign;
+}
+inline int isinfinity(double x) {
+    return !_finite(x);
+}
+#endif
+
+template <typename T>
+struct IsLongDouble {
+    enum { VALUE = 0 };
+};
+
+template <>
+struct IsLongDouble<long double> {
+    enum { VALUE = 1 };
+};
+
+template <typename Char>
+class BasicCharTraits {
+public:
+#if _SECURE_SCL
+    typedef stdext::checked_array_iterator<Char*> CharPtr;
+#else
+    typedef Char *CharPtr;
+#endif
+};
+
+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:
+    typedef const wchar_t *UnsupportedStrType;
+
+    static char convert(char value) {
+        return value;
+    }
+
+    // Formats a floating-point number.
+    template <typename T>
+    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:
+    typedef const char *UnsupportedStrType;
+
+    static wchar_t convert(char value) {
+        return value;
+    }
+    static wchar_t convert(wchar_t value) {
+        return value;
+    }
+
+    template <typename T>
+    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;
+};
+
+// 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);
+
+void report_unknown_type(char code, const char *type);
+
+extern const uint32_t POWERS_OF_10_32[];
+extern const uint64_t POWERS_OF_10_64[];
+
+#if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__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.
+    unsigned t = (64 - __builtin_clzll(n | 1)) * 1233 >> 12;
+    return t - (n < POWERS_OF_10_64[t]) + 1;
+}
+# if FMT_GCC_VERSION >= 400 || FMT_HAS_BUILTIN(__builtin_clz)
+// Optional version of count_digits for better performance on 32-bit platforms.
+inline unsigned count_digits(uint32_t n) {
+    uint32_t t = (32 - __builtin_clz(n | 1)) * 1233 >> 12;
+    return t - (n < POWERS_OF_10_32[t]) + 1;
+}
+# endif
+#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
+
+extern const char DIGITS[];
+
+// Formats a decimal unsigned integer value writing into buffer.
+template <typename UInt, typename Char>
+inline void format_decimal(Char *buffer, UInt value, unsigned num_digits) {
+    --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 = (value % 100) * 2;
+        value /= 100;
+        buffer[num_digits] = DIGITS[index + 1];
+        buffer[num_digits - 1] = DIGITS[index];
+        num_digits -= 2;
+    }
+    if (value < 10) {
+        *buffer = static_cast<char>('0' + value);
+        return;
+    }
+    unsigned index = static_cast<unsigned>(value * 2);
+    buffer[1] = DIGITS[index + 1];
+    buffer[0] = DIGITS[index];
+}
+
+#ifdef _WIN32
+// 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:
+    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() {}
+    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.
+    int convert(WStringRef s);
+};
+#endif
+
+void format_system_error(fmt::Writer &out, int error_code,
+                         fmt::StringRef message) FMT_NOEXCEPT(true);
+
+#ifdef _WIN32
+void format_windows_error(fmt::Writer &out, int error_code,
+                          fmt::StringRef message) FMT_NOEXCEPT(true);
+#endif
+
+// Computes max(Arg, 1) at compile time. It is used to avoid errors about
+// allocating an array of 0 size.
+template <unsigned Arg>
+struct NonZero {
+    enum { VALUE = Arg };
+};
+
+template <>
+struct NonZero<0> {
+    enum { VALUE = 1 };
+};
+
+// The value of a formatting argument. It is a POD type to allow storage in
+// internal::MemoryBuffer.
+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;
+    };
+};
+
+struct Arg : Value {
+    enum Type {
+        NONE,
+        // Integer types should go first,
+        INT, UINT, LONG_LONG, ULONG_LONG, CHAR, LAST_INTEGER_TYPE = CHAR,
+        // followed by floating-point types.
+        DOUBLE, LONG_DOUBLE, LAST_NUMERIC_TYPE = LONG_DOUBLE,
+        CSTRING, STRING, WSTRING, POINTER, CUSTOM
+    };
+    Type type;
+};
+
+// Makes a Value object from any type.
+template <typename Char>
+class MakeValue : public Value {
+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);
+
+    void set_string(StringRef str) {
+        string.value = str.c_str();
+        string.size = str.size();
+    }
+
+    void set_string(WStringRef str) {
+        CharTraits<Char>::convert(wchar_t());
+        wstring.value = str.c_str();
+        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<BasicFormatter<Char>*>(formatter),
+               *static_cast<const Char**>(format_str_ptr),
+               *static_cast<const T*>(arg));
+    }
+
+public:
+    MakeValue() {}
+
+#define FMT_MAKE_VALUE(Type, field, TYPE) \
+  MakeValue(Type value) { field = value; } \
+  static uint64_t type(Type) { return Arg::TYPE; }
+
+    FMT_MAKE_VALUE(bool, int_value, INT)
+    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 (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 (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, CHAR)
+    FMT_MAKE_VALUE(unsigned char, int_value, CHAR)
+    FMT_MAKE_VALUE(char, int_value, CHAR)
+
+    MakeValue(wchar_t value) {
+        int_value = internal::CharTraits<Char>::convert(value);
+    }
+    static uint64_t type(wchar_t) {
+        return Arg::CHAR;
+    }
+
+#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(const signed char *, sstring.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_STR_VALUE(wchar_t *, WSTRING)
+    FMT_MAKE_STR_VALUE(const wchar_t *, WSTRING)
+    FMT_MAKE_STR_VALUE(const std::wstring &, WSTRING)
+    FMT_MAKE_STR_VALUE(WStringRef, WSTRING)
+
+    FMT_MAKE_VALUE(void *, pointer, POINTER)
+    FMT_MAKE_VALUE(const void *, pointer, POINTER)
+
+    template <typename T>
+    MakeValue(const T &value) {
+        custom.value = &value;
+        custom.format = &format_custom_arg<T>;
+    }
+    template <typename T>
+    static uint64_t type(const T &) {
+        return Arg::CUSTOM;
+    }
+};
+
+#define FMT_DISPATCH(call) static_cast<Impl*>(this)->call
+
+// An argument visitor.
+// To use ArgVisitor define a subclass that implements some or all of the
+// visit methods with the same signatures as the methods in ArgVisitor,
+// for example, visit_int(int).
+// Specify the subclass name as the Impl template parameter. Then calling
+// 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 visit_double(double) method of a subclass will be called.
+// If the subclass doesn't contain a method with this signature, then
+// a corresponding method of ArgVisitor will be called.
+//
+// Example:
+//  class MyArgVisitor : public ArgVisitor<MyArgVisitor, void> {
+//   public:
+//    void visit_int(int value) { print("{}", value); }
+//    void visit_double(double value) { print("{}", value ); }
+//  };
+//
+// ArgVisitor uses the curiously recurring template pattern:
+// http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern
+template <typename Impl, typename Result>
+class ArgVisitor {
+public:
+    Result visit_unhandled_arg() {
+        return Result();
+    }
+
+    Result visit_int(int value) {
+        return FMT_DISPATCH(visit_any_int(value));
+    }
+    Result visit_long_long(LongLong value) {
+        return FMT_DISPATCH(visit_any_int(value));
+    }
+    Result visit_uint(unsigned value) {
+        return FMT_DISPATCH(visit_any_int(value));
+    }
+    Result visit_ulong_long(ULongLong value) {
+        return FMT_DISPATCH(visit_any_int(value));
+    }
+    Result visit_char(int value) {
+        return FMT_DISPATCH(visit_any_int(value));
+    }
+    template <typename T>
+    Result visit_any_int(T) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+
+    Result visit_double(double value) {
+        return FMT_DISPATCH(visit_any_double(value));
+    }
+    Result visit_long_double(long double value) {
+        return FMT_DISPATCH(visit_any_double(value));
+    }
+    template <typename T>
+    Result visit_any_double(T) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+
+    Result visit_string(Arg::StringValue<char>) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+    Result visit_wstring(Arg::StringValue<wchar_t>) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+    Result visit_pointer(const void *) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+    Result visit_custom(Arg::CustomValue) {
+        return FMT_DISPATCH(visit_unhandled_arg());
+    }
+
+    Result visit(const Arg &arg) {
+        switch (arg.type) {
+        default:
+            assert(false);
+        // Fall through.
+        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::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::CHAR:
+            return FMT_DISPATCH(visit_char(arg.int_value));
+        case Arg::CSTRING: {
+            Value::StringValue<char> str = arg.string;
+            str.size = 0;
+            return FMT_DISPATCH(visit_string(str));
+        }
+        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));
+        }
+    }
+};
+
+class RuntimeError : public std::runtime_error {
+protected:
+    RuntimeError() : std::runtime_error("") {}
+};
+
+template <typename Char>
+class ArgFormatter;
+}  // namespace internal
+
+/**
+An argument list.
+*/
+class ArgList {
+private:
+    uint64_t types_;
+    const internal::Value *values_;
+
+public:
+    // Maximum number of arguments that can be passed in ArgList.
+    enum { MAX_ARGS = 16 };
+
+    ArgList() : types_(0) {}
+    ArgList(ULongLong types, const internal::Value *values)
+        : types_(types), values_(values) {}
+
+    /**
+    Returns the argument at specified index.
+    */
+    internal::Arg operator[](unsigned index) const {
+        using internal::Arg;
+        Arg arg;
+        if (index >= MAX_ARGS) {
+            arg.type = Arg::NONE;
+            return arg;
+        }
+        unsigned shift = index * 4;
+        uint64_t mask = 0xf;
+        Arg::Type type =
+            static_cast<Arg::Type>((types_ & (mask << shift)) >> shift);
+        arg.type = type;
+        if (type != Arg::NONE) {
+            internal::Value &value = arg;
+            value = values_[index];
+        }
+        return arg;
+    }
+};
+
+struct FormatSpec;
+
+namespace internal {
+
+class FormatterBase {
+private:
+    ArgList args_;
+    int next_arg_index_;
+
+    // Returns the argument with specified index.
+    Arg do_get_arg(unsigned arg_index, const char *&error);
+
+protected:
+    void set_args(const ArgList &args) {
+        args_ = args;
+        next_arg_index_ = 0;
+    }
+
+    // Returns the next argument.
+    Arg next_arg(const char *&error);
+
+    // Checks if manual indexing is used and returns the argument with
+    // specified index.
+    Arg get_arg(unsigned arg_index, const char *&error);
+
+    template <typename Char>
+    void write(BasicWriter<Char> &w, const Char *start, const Char *end) {
+        if (start != end)
+            w << BasicStringRef<Char>(start, 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:
+    void format(BasicWriter<Char> &writer,
+                BasicStringRef<Char> format, const ArgList &args);
+};
+}  // namespace internal
+
+// A formatter.
+template <typename Char>
+class BasicFormatter : private internal::FormatterBase {
+private:
+    BasicWriter<Char> &writer_;
+    const Char *start_;
+
+    // Parses argument index and returns corresponding argument.
+    internal::Arg parse_arg_index(const Char *&s);
+
+public:
+    explicit BasicFormatter(BasicWriter<Char> &w) : writer_(w) {}
+
+    BasicWriter<Char> &writer() {
+        return writer_;
+    }
+
+    void format(BasicStringRef<Char> format_str, const ArgList &args);
+
+    const Char *format(const Char *&format_str, const internal::Arg &arg);
+};
+
+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 value, const SpecT &spec = SpecT())
+        : SpecT(spec), value_(value) {}
+
+    T value() const {
+        return value_;
+    }
+};
+
+// A string format specifier.
+template <typename T>
+class StrFormatSpec : public AlignSpec {
+private:
+    const T *str_;
+
+public:
+    StrFormatSpec(const T *str, unsigned width, wchar_t fill)
+        : AlignSpec(width, fill), str_(str) {}
+
+    const T *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);
+}
+
+// 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<char>::type(arg);
+}
+
+#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_MAKE_REF_char(n) fmt::internal::MakeValue<char>(v##n)
+# define FMT_MAKE_REF_wchar_t(n) fmt::internal::MakeValue<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 arg1, const Args & ... args) { \
+    const fmt::internal::Value values[ \
+      fmt::internal::NonZero<sizeof...(Args)>::VALUE] = { \
+      fmt::internal::MakeValue<Char>(args)... \
+        }; \
+    func(arg1, ArgList(fmt::internal::make_type(args...), values)); \
+      }
+
+// 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) { \
+    using fmt::internal::MakeValue; \
+    const fmt::internal::Value values[ \
+        fmt::internal::NonZero<sizeof...(Args)>::VALUE] = { \
+      MakeValue<Char>(args)... \
+        }; \
+    func(arg0, arg1, ArgList(fmt::internal::make_type(args...), values)); \
+      }
+
+#else
+
+# define FMT_MAKE_REF(n) fmt::internal::MakeValue<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::Value vals[] = {FMT_GEN(n, FMT_MAKE_REF)}; \
+    func(arg1, fmt::ArgList( \
+      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), vals)); \
+      }
+
+// Emulates a variadic function returning void on a pre-C++11 compiler.
+# define FMT_VARIADIC_VOID(func, arg_type) \
+  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::Value vals[] = {FMT_GEN(n, FMT_MAKE_REF)}; \
+    func(arg0, arg1, fmt::ArgList( \
+      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), vals)); \
+      }
+
+// 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 error_code, StringRef format_str, ArgList args);
+
+protected:
+    int error_code_;
+
+    typedef char Char;  // For FMT_VARIADIC_CTOR.
+
+    SystemError() {}
+
+public:
+    /**
+    \rst
+    Constructs a :cpp:class:`fmt::SystemError` object with the description
+    of the form "*<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``.
+    \endrst
+    */
+    SystemError(int error_code, StringRef message) {
+        init(error_code, message, ArgList());
+    }
+    FMT_VARIADIC_CTOR(SystemError, init, int, StringRef)
+
+    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 :cpp: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.
+    internal::Buffer<Char> &buffer_;
+
+    FMT_DISALLOW_COPY_AND_ASSIGN(BasicWriter);
+
+    typedef typename internal::CharTraits<Char>::CharPtr CharPtr;
+
+#if _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);
+    }
+
+    // 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::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 method is private to disallow writing a wide string to a
+    // char stream and vice versa. 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::CharTraits<Char>::UnsupportedStrType);
+
+    friend class internal::ArgFormatter<Char>;
+    friend class internal::PrintfFormatter<Char>;
+
+protected:
+    /**
+    Constructs a ``BasicWriter`` object.
+    */
+    explicit BasicWriter(internal::Buffer<Char> &b) : buffer_(b) {}
+
+public:
+    /**
+    Destroys a ``BasicWriter`` object.
+    */
+    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(true) {
+        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];
+    }
+
+    /**
+    Returns the content of the output buffer as an `std::string`.
+    */
+    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 :meth:`data`, :meth:`c_str` or :meth:`str`
+    methods.
+
+    See also :ref:`syntax`.
+    \endrst
+    */
+    void write(BasicStringRef<Char> format, ArgList args) {
+        BasicFormatter<Char>(*this).format(format, args);
+    }
+    FMT_VARIADIC_VOID(write, BasicStringRef<Char>)
+
+    BasicWriter &operator<<(int value) {
+        return *this << IntFormatSpec<int>(value);
+    }
+    BasicWriter &operator<<(unsigned value) {
+        return *this << IntFormatSpec<unsigned>(value);
+    }
+    BasicWriter &operator<<(long value) {
+        return *this << IntFormatSpec<long>(value);
+    }
+    BasicWriter &operator<<(unsigned long value) {
+        return *this << IntFormatSpec<unsigned long>(value);
+    }
+    BasicWriter &operator<<(LongLong value) {
+        return *this << IntFormatSpec<LongLong>(value);
+    }
+
+    /**
+    Formats *value* and writes it to the stream.
+    */
+    BasicWriter &operator<<(ULongLong value) {
+        return *this << IntFormatSpec<ULongLong>(value);
+    }
+
+    BasicWriter &operator<<(double value) {
+        write_double(value, FormatSpec());
+        return *this;
+    }
+
+    /**
+    Formats *value* using the general format for floating-point numbers
+    (``'g'``) and writes it to the stream.
+    */
+    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<<(wchar_t value) {
+        buffer_.push_back(internal::CharTraits<Char>::convert(value));
+        return *this;
+    }
+
+    /**
+    Writes *value* to the stream.
+    */
+    BasicWriter &operator<<(fmt::BasicStringRef<Char> value) {
+        const Char *str = value.c_str();
+        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();
+        // TODO: error if fill is not convertible to Char
+        write_str(s, std::char_traits<Char>::length(s), spec);
+        return *this;
+    }
+
+    void clear() FMT_NOEXCEPT(true) {
+        buffer_.clear();
+    }
+};
+
+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 = static_cast<Char>(spec.fill());
+        if (spec.align() == ALIGN_RIGHT) {
+            std::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::fill_n(out + size, spec.width() - size, fill);
+        }
+    }
+    else {
+        out = grow_buffer(size);
+    }
+    std::copy(s, s + size, out);
+    return out;
+}
+
+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 = static_cast<Char>(fill);
+    std::fill_n(buffer, left_padding, fill_char);
+    buffer += left_padding;
+    CharPtr content = buffer;
+    std::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 = static_cast<Char>(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 + 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::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::fill(p, p + fill_size, fill);
+        }
+        return result;
+    }
+    unsigned size = prefix_size + num_digits;
+    if (width <= size) {
+        CharPtr p = grow_buffer(size);
+        std::copy(prefix, prefix + prefix_size, p);
+        return p + size - 1;
+    }
+    CharPtr p = grow_buffer(width);
+    CharPtr end = p + width;
+    if (align == ALIGN_LEFT) {
+        std::copy(prefix, prefix + prefix_size, p);
+        p += size;
+        std::fill(p, end, fill);
+    }
+    else if (align == ALIGN_CENTER) {
+        p = fill_padding(p, width, size, fill);
+        std::copy(prefix, prefix + prefix_size, p);
+        p += size;
+    }
+    else {
+        if (align == ALIGN_NUMERIC) {
+            if (prefix_size != 0) {
+                p = std::copy(prefix, prefix + prefix_size, p);
+                size -= prefix_size;
+            }
+        }
+        else {
+            std::copy(prefix, prefix + prefix_size, end - size);
+        }
+        std::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 = 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 - num_digits;
+        internal::format_decimal(get(p), abs_value, num_digits);
+        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-- = '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-- = '0' + (n & 7);
+        } while ((n >>= 3) != 0);
+        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':
+#ifdef _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 getsign instead of value < 0 because the latter is always
+    // false for NaN.
+    if (internal::getsign(static_cast<double>(value))) {
+        sign = '-';
+        value = -value;
+    }
+    else if (spec.flag(SIGN_FLAG)) {
+        sign = spec.flag(PLUS_FLAG) ? '+' : ' ';
+    }
+
+    if (value != value) {
+        // Format NaN ourselves because sprintf's output is not consistent
+        // across platforms.
+        std::size_t size = 4;
+        const char *nan = upper ? " NAN" : " nan";
+        if (!sign) {
+            --size;
+            ++nan;
+        }
+        CharPtr out = write_str(nan, size, spec);
+        if (sign)
+            *out = sign;
+        return;
+    }
+
+    if (internal::isinfinity(value)) {
+        // Format infinity ourselves because sprintf's output is not consistent
+        // across platforms.
+        std::size_t size = 4;
+        const char *inf = upper ? " INF" : " inf";
+        if (!sign) {
+            --size;
+            ++inf;
+        }
+        CharPtr out = write_str(inf, size, spec);
+        if (sign)
+            *out = sign;
+        return;
+    }
+
+    std::size_t offset = buffer_.size();
+    unsigned width = spec.width();
+    if (sign) {
+        buffer_.reserve(buffer_.size() + (std::max)(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++ = '*';
+    }
+    if (internal::IsLongDouble<T>::VALUE)
+        *format_ptr++ = 'L';
+    *format_ptr++ = type;
+    *format_ptr = '\0';
+
+    // Format using snprintf.
+    Char fill = static_cast<Char>(spec.fill());
+    for (;;) {
+        std::size_t size = buffer_.capacity() - offset;
+#if _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 (size == 0) {
+            buffer_.reserve(offset + 1);
+            size = buffer_.capacity() - offset;
+        }
+#endif
+        Char *start = &buffer_[offset];
+        int n = internal::CharTraits<Char>::format_float(
+                    start, size, format, width_for_sprintf, spec.precision(), value);
+        if (n >= 0 && offset + n < buffer_.capacity()) {
+            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() > static_cast<unsigned>(n)) {
+                unsigned width = spec.width();
+                CharPtr p = grow_buffer(width);
+                std::copy(p, p + n, p + (width - n) / 2);
+                fill_padding(p, spec.width(), n, fill);
+                return;
+            }
+            if (spec.fill() != ' ' || sign) {
+                while (*start == ' ')
+                    *start++ = fill;
+                if (sign)
+                    *(start - 1) = sign;
+            }
+            grow_buffer(n);
+            return;
+        }
+        // If n is negative we ask to increase the capacity by at least 1,
+        // but as std::vector, the buffer grows exponentially.
+        buffer_.reserve(n >= 0 ? offset + n + 1 : buffer_.capacity() + 1);
+    }
+}
+
+/**
+\rst
+This 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  | BasicWriter<char, std::allocator<char>>       |
++---------------+-----------------------------------------------+
+| WMemoryWriter | BasicWriter<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
+    /**
+    Constructs a ``BasicMemoryWriter`` object moving the content of the other
+    object to it.
+    */
+    BasicMemoryWriter(BasicMemoryWriter &&other)
+        : BasicWriter<Char>(buffer_), buffer_(std::move(other.buffer_)) {
+    }
+
+    /**
+    Moves the content of the other ``BasicMemoryWriter`` object to this one.
+    */
+    BasicMemoryWriter &operator=(BasicMemoryWriter &&other) {
+        buffer_ = std::move(other.buffer_);
+        return *this;
+    }
+#endif
+};
+
+typedef BasicMemoryWriter<char> MemoryWriter;
+typedef BasicMemoryWriter<wchar_t> WMemoryWriter;
+
+// Formats a value.
+template <typename Char, typename T>
+void format(BasicFormatter<Char> &f, const Char *&format_str, const T &value) {
+    std::basic_ostringstream<Char> os;
+    os << value;
+    internal::Arg arg;
+    internal::Value &arg_value = arg;
+    std::basic_string<Char> str = os.str();
+    arg_value = internal::MakeValue<Char>(str);
+    arg.type = internal::Arg::STRING;
+    format_str = f.format(format_str, arg);
+}
+
+// Reports a system error without throwing an exception.
+// Can be used to report errors from destructors.
+void report_system_error(int error_code, StringRef message) FMT_NOEXCEPT(true);
+
+#ifdef _WIN32
+
+/**
+A Windows error.
+*/
+class WindowsError : public SystemError {
+private:
+    void init(int error_code, StringRef format_str, ArgList args);
+
+public:
+    /**
+    \rst
+    Constructs a :cpp:class:`fmt::WindowsError` object with the description
+    of the form "*<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``.
+    \endrst
+    */
+    WindowsError(int error_code, StringRef message) {
+        init(error_code, message, ArgList());
+    }
+    FMT_VARIADIC_CTOR(WindowsError, init, int, StringRef)
+};
+
+// Reports a Windows error without throwing an exception.
+// Can be used to report errors from destructors.
+void report_windows_error(int error_code, StringRef message) FMT_NOEXCEPT(true);
+
+#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:
+PrintColored(fmt::RED, "Elapsed time: {0:.2f} seconds") << 1.23;
+*/
+void print_colored(Color c, StringRef 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(StringRef format_str, ArgList args) {
+    MemoryWriter w;
+    w.write(format_str, args);
+    return w.str();
+}
+
+inline std::wstring format(WStringRef 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
+*/
+void print(std::FILE *f, StringRef format_str, ArgList args);
+
+/**
+\rst
+Prints formatted data to ``stdout``.
+
+**Example**::
+
+print("Elapsed time: {0:.2f} seconds", 1.23);
+\endrst
+*/
+void print(StringRef format_str, ArgList args);
+
+/**
+\rst
+Prints formatted data to the stream *os*.
+
+**Example**::
+
+print(cerr, "Don't {}!", "panic");
+\endrst
+*/
+void print(std::ostream &os, StringRef format_str, ArgList args);
+
+template <typename Char>
+void printf(BasicWriter<Char> &w, BasicStringRef<Char> format, ArgList args) {
+    internal::PrintfFormatter<Char>().format(w, format, args);
+}
+
+/**
+\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(StringRef format, ArgList args) {
+    MemoryWriter 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
+*/
+int fprintf(std::FILE *f, StringRef format, ArgList args);
+
+/**
+\rst
+Prints formatted data to ``stdout``.
+
+**Example**::
+
+fmt::printf("Elapsed time: %.2f seconds", 1.23);
+\endrst
+*/
+inline int printf(StringRef 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 = (value % 100) * 2;
+            value /= 100;
+            *--buffer_end = internal::DIGITS[index + 1];
+            *--buffer_end = internal::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::DIGITS[index + 1];
+        *--buffer_end = internal::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 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_;
+    }
+
+    /**
+    Returns the content of the output buffer as an `std::string`.
+    */
+    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) {
+    typename internal::IntTraits<T>::MainType abs_value = 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::DIGITS[index];
+        *buffer++ = internal::DIGITS[index + 1];
+        return;
+    }
+    unsigned num_digits = internal::count_digits(abs_value);
+    internal::format_decimal(buffer, abs_value, num_digits);
+    buffer += num_digits;
+}
+}
+
+#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) { \
+    using fmt::internal::Value; \
+    const Value values[fmt::internal::NonZero<sizeof...(Args)>::VALUE] = { \
+      fmt::internal::MakeValue<Char>(args)... \
+    }; \
+    call(FMT_FOR_EACH(FMT_GET_ARG_NAME, __VA_ARGS__), fmt::ArgList( \
+      fmt::internal::make_type(args...), values)); \
+  }
+#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)) { \
+    const fmt::internal::Value vals[] = {FMT_GEN(n, FMT_MAKE_REF_##Char)}; \
+    call(FMT_FOR_EACH(FMT_GET_ARG_NAME, __VA_ARGS__), fmt::ArgList( \
+      fmt::internal::make_type(FMT_GEN(n, FMT_MAKE_REF2)), vals)); \
+  }
+
+# 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__)
+
+namespace fmt {
+FMT_VARIADIC(std::string, format, StringRef)
+FMT_VARIADIC_W(std::wstring, format, WStringRef)
+FMT_VARIADIC(void, print, StringRef)
+FMT_VARIADIC(void, print, std::FILE *, StringRef)
+FMT_VARIADIC(void, print, std::ostream &, StringRef)
+FMT_VARIADIC(void, print_colored, Color, StringRef)
+FMT_VARIADIC(std::string, sprintf, StringRef)
+FMT_VARIADIC(int, printf, StringRef)
+FMT_VARIADIC(int, fprintf, std::FILE *, StringRef)
+}
+
+// Restore warnings.
+#if FMT_GCC_VERSION >= 406
+# pragma GCC diagnostic pop
+#endif
+
+#define FMT_HEADER_ONLY
+# include "format.cc"
+#undef FMT_HEADER_ONLY
+
+#endif  // FMT_FORMAT_H_