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+/*
+ Formatting library for C++
+
+ Copyright (c) 2012 - present, Victor Zverovich
+
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+ --- Optional exception to the license ---
+
+ As an exception, if, as a result of your compiling your source code, portions
+ of this Software are embedded into a machine-executable object form of such
+ source code, you may redistribute such embedded portions in such object form
+ without including the above copyright and permission notices.
+ */
+
+#ifndef FMT_FORMAT_H_
+#define FMT_FORMAT_H_
+
+#include <algorithm>
+#include <cerrno>
+#include <cmath>
+#include <cstdint>
+#include <limits>
+#include <memory>
+#include <stdexcept>
+
+#include "core.h"
+
+#ifdef __INTEL_COMPILER
+# define FMT_ICC_VERSION __INTEL_COMPILER
+#elif defined(__ICL)
+# define FMT_ICC_VERSION __ICL
+#else
+# define FMT_ICC_VERSION 0
+#endif
+
+#ifdef __NVCC__
+# define FMT_CUDA_VERSION (__CUDACC_VER_MAJOR__ * 100 + __CUDACC_VER_MINOR__)
+#else
+# define FMT_CUDA_VERSION 0
+#endif
+
+#ifdef __has_builtin
+# define FMT_HAS_BUILTIN(x) __has_builtin(x)
+#else
+# define FMT_HAS_BUILTIN(x) 0
+#endif
+
+#if FMT_GCC_VERSION || FMT_CLANG_VERSION
+# define FMT_NOINLINE __attribute__((noinline))
+#else
+# define FMT_NOINLINE
+#endif
+
+#if __cplusplus == 201103L || __cplusplus == 201402L
+# if defined(__INTEL_COMPILER) || defined(__PGI)
+# define FMT_FALLTHROUGH
+# elif defined(__clang__)
+# define FMT_FALLTHROUGH [[clang::fallthrough]]
+# elif FMT_GCC_VERSION >= 700 && \
+ (!defined(__EDG_VERSION__) || __EDG_VERSION__ >= 520)
+# define FMT_FALLTHROUGH [[gnu::fallthrough]]
+# else
+# define FMT_FALLTHROUGH
+# endif
+#elif FMT_HAS_CPP17_ATTRIBUTE(fallthrough) || \
+ (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)
+# define FMT_FALLTHROUGH [[fallthrough]]
+#else
+# define FMT_FALLTHROUGH
+#endif
+
+#ifndef FMT_MAYBE_UNUSED
+# if FMT_HAS_CPP17_ATTRIBUTE(maybe_unused)
+# define FMT_MAYBE_UNUSED [[maybe_unused]]
+# else
+# define FMT_MAYBE_UNUSED
+# endif
+#endif
+
+#ifndef FMT_THROW
+# if FMT_EXCEPTIONS
+# if FMT_MSC_VER || FMT_NVCC
+FMT_BEGIN_NAMESPACE
+namespace detail {
+template <typename Exception> inline void do_throw(const Exception& x) {
+ // Silence unreachable code warnings in MSVC and NVCC because these
+ // are nearly impossible to fix in a generic code.
+ volatile bool b = true;
+ if (b) throw x;
+}
+} // namespace detail
+FMT_END_NAMESPACE
+# define FMT_THROW(x) detail::do_throw(x)
+# else
+# define FMT_THROW(x) throw x
+# endif
+# else
+# define FMT_THROW(x) \
+ do { \
+ static_cast<void>(sizeof(x)); \
+ FMT_ASSERT(false, ""); \
+ } while (false)
+# endif
+#endif
+
+#if FMT_EXCEPTIONS
+# define FMT_TRY try
+# define FMT_CATCH(x) catch (x)
+#else
+# define FMT_TRY if (true)
+# define FMT_CATCH(x) if (false)
+#endif
+
+#ifndef FMT_USE_USER_DEFINED_LITERALS
+// EDG based compilers (Intel, NVIDIA, Elbrus, etc), GCC and MSVC support UDLs.
+# if (FMT_HAS_FEATURE(cxx_user_literals) || FMT_GCC_VERSION >= 407 || \
+ FMT_MSC_VER >= 1900) && \
+ (!defined(__EDG_VERSION__) || __EDG_VERSION__ >= /* UDL feature */ 480)
+# define FMT_USE_USER_DEFINED_LITERALS 1
+# else
+# define FMT_USE_USER_DEFINED_LITERALS 0
+# endif
+#endif
+
+#ifndef FMT_USE_UDL_TEMPLATE
+// EDG frontend based compilers (icc, nvcc, PGI, etc) and GCC < 6.4 do not
+// properly support UDL templates and GCC >= 9 warns about them.
+# if FMT_USE_USER_DEFINED_LITERALS && \
+ (!defined(__EDG_VERSION__) || __EDG_VERSION__ >= 501) && \
+ ((FMT_GCC_VERSION >= 604 && __cplusplus >= 201402L) || \
+ FMT_CLANG_VERSION >= 304) && \
+ !defined(__PGI) && !defined(__NVCC__)
+# define FMT_USE_UDL_TEMPLATE 1
+# else
+# define FMT_USE_UDL_TEMPLATE 0
+# endif
+#endif
+
+#ifndef FMT_USE_FLOAT
+# define FMT_USE_FLOAT 1
+#endif
+
+#ifndef FMT_USE_DOUBLE
+# define FMT_USE_DOUBLE 1
+#endif
+
+#ifndef FMT_USE_LONG_DOUBLE
+# define FMT_USE_LONG_DOUBLE 1
+#endif
+
+// Defining FMT_REDUCE_INT_INSTANTIATIONS to 1, will reduce the number of
+// int_writer template instances to just one by only using the largest integer
+// type. This results in a reduction in binary size but will cause a decrease in
+// integer formatting performance.
+#if !defined(FMT_REDUCE_INT_INSTANTIATIONS)
+# define FMT_REDUCE_INT_INSTANTIATIONS 0
+#endif
+
+// __builtin_clz is broken in clang with Microsoft CodeGen:
+// https://github.com/fmtlib/fmt/issues/519
+#if (FMT_GCC_VERSION || FMT_HAS_BUILTIN(__builtin_clz)) && !FMT_MSC_VER
+# define FMT_BUILTIN_CLZ(n) __builtin_clz(n)
+#endif
+#if (FMT_GCC_VERSION || FMT_HAS_BUILTIN(__builtin_clzll)) && !FMT_MSC_VER
+# define FMT_BUILTIN_CLZLL(n) __builtin_clzll(n)
+#endif
+#if (FMT_GCC_VERSION || FMT_HAS_BUILTIN(__builtin_ctz))
+# define FMT_BUILTIN_CTZ(n) __builtin_ctz(n)
+#endif
+#if (FMT_GCC_VERSION || FMT_HAS_BUILTIN(__builtin_ctzll))
+# define FMT_BUILTIN_CTZLL(n) __builtin_ctzll(n)
+#endif
+
+#if FMT_MSC_VER
+# include <intrin.h> // _BitScanReverse[64], _BitScanForward[64], _umul128
+#endif
+
+// Some compilers masquerade as both MSVC and GCC-likes or otherwise support
+// __builtin_clz and __builtin_clzll, so only define FMT_BUILTIN_CLZ using the
+// MSVC intrinsics if the clz and clzll builtins are not available.
+#if FMT_MSC_VER && !defined(FMT_BUILTIN_CLZLL) && \
+ !defined(FMT_BUILTIN_CTZLL) && !defined(_MANAGED)
+FMT_BEGIN_NAMESPACE
+namespace detail {
+// Avoid Clang with Microsoft CodeGen's -Wunknown-pragmas warning.
+# ifndef __clang__
+# pragma intrinsic(_BitScanForward)
+# pragma intrinsic(_BitScanReverse)
+# endif
+# if defined(_WIN64) && !defined(__clang__)
+# pragma intrinsic(_BitScanForward64)
+# pragma intrinsic(_BitScanReverse64)
+# endif
+
+inline int clz(uint32_t x) {
+ unsigned long r = 0;
+ _BitScanReverse(&r, x);
+ FMT_ASSERT(x != 0, "");
+ // Static analysis complains about using uninitialized data
+ // "r", but the only way that can happen is if "x" is 0,
+ // which the callers guarantee to not happen.
+ FMT_SUPPRESS_MSC_WARNING(6102)
+ return 31 ^ static_cast<int>(r);
+}
+# define FMT_BUILTIN_CLZ(n) detail::clz(n)
+
+inline int clzll(uint64_t x) {
+ unsigned long r = 0;
+# ifdef _WIN64
+ _BitScanReverse64(&r, x);
+# else
+ // Scan the high 32 bits.
+ if (_BitScanReverse(&r, static_cast<uint32_t>(x >> 32))) return 63 ^ (r + 32);
+ // Scan the low 32 bits.
+ _BitScanReverse(&r, static_cast<uint32_t>(x));
+# endif
+ FMT_ASSERT(x != 0, "");
+ FMT_SUPPRESS_MSC_WARNING(6102) // Suppress a bogus static analysis warning.
+ return 63 ^ static_cast<int>(r);
+}
+# define FMT_BUILTIN_CLZLL(n) detail::clzll(n)
+
+inline int ctz(uint32_t x) {
+ unsigned long r = 0;
+ _BitScanForward(&r, x);
+ FMT_ASSERT(x != 0, "");
+ FMT_SUPPRESS_MSC_WARNING(6102) // Suppress a bogus static analysis warning.
+ return static_cast<int>(r);
+}
+# define FMT_BUILTIN_CTZ(n) detail::ctz(n)
+
+inline int ctzll(uint64_t x) {
+ unsigned long r = 0;
+ FMT_ASSERT(x != 0, "");
+ FMT_SUPPRESS_MSC_WARNING(6102) // Suppress a bogus static analysis warning.
+# ifdef _WIN64
+ _BitScanForward64(&r, x);
+# else
+ // Scan the low 32 bits.
+ if (_BitScanForward(&r, static_cast<uint32_t>(x))) return static_cast<int>(r);
+ // Scan the high 32 bits.
+ _BitScanForward(&r, static_cast<uint32_t>(x >> 32));
+ r += 32;
+# endif
+ return static_cast<int>(r);
+}
+# define FMT_BUILTIN_CTZLL(n) detail::ctzll(n)
+} // namespace detail
+FMT_END_NAMESPACE
+#endif
+
+// Enable the deprecated numeric alignment.
+#ifndef FMT_DEPRECATED_NUMERIC_ALIGN
+# define FMT_DEPRECATED_NUMERIC_ALIGN 0
+#endif
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+// An equivalent of `*reinterpret_cast<Dest*>(&source)` that doesn't have
+// undefined behavior (e.g. due to type aliasing).
+// Example: uint64_t d = bit_cast<uint64_t>(2.718);
+template <typename Dest, typename Source>
+inline Dest bit_cast(const Source& source) {
+ static_assert(sizeof(Dest) == sizeof(Source), "size mismatch");
+ Dest dest;
+ std::memcpy(&dest, &source, sizeof(dest));
+ return dest;
+}
+
+inline bool is_big_endian() {
+ const auto u = 1u;
+ struct bytes {
+ char data[sizeof(u)];
+ };
+ return bit_cast<bytes>(u).data[0] == 0;
+}
+
+// A fallback implementation of uintptr_t for systems that lack it.
+struct fallback_uintptr {
+ unsigned char value[sizeof(void*)];
+
+ fallback_uintptr() = default;
+ explicit fallback_uintptr(const void* p) {
+ *this = bit_cast<fallback_uintptr>(p);
+ if (is_big_endian()) {
+ for (size_t i = 0, j = sizeof(void*) - 1; i < j; ++i, --j)
+ std::swap(value[i], value[j]);
+ }
+ }
+};
+#ifdef UINTPTR_MAX
+using uintptr_t = ::uintptr_t;
+inline uintptr_t to_uintptr(const void* p) { return bit_cast<uintptr_t>(p); }
+#else
+using uintptr_t = fallback_uintptr;
+inline fallback_uintptr to_uintptr(const void* p) {
+ return fallback_uintptr(p);
+}
+#endif
+
+// Returns the largest possible value for type T. Same as
+// std::numeric_limits<T>::max() but shorter and not affected by the max macro.
+template <typename T> constexpr T max_value() {
+ return (std::numeric_limits<T>::max)();
+}
+template <typename T> constexpr int num_bits() {
+ return std::numeric_limits<T>::digits;
+}
+// std::numeric_limits<T>::digits may return 0 for 128-bit ints.
+template <> constexpr int num_bits<int128_t>() { return 128; }
+template <> constexpr int num_bits<uint128_t>() { return 128; }
+template <> constexpr int num_bits<fallback_uintptr>() {
+ return static_cast<int>(sizeof(void*) *
+ std::numeric_limits<unsigned char>::digits);
+}
+
+FMT_INLINE void assume(bool condition) {
+ (void)condition;
+#if FMT_HAS_BUILTIN(__builtin_assume)
+ __builtin_assume(condition);
+#endif
+}
+
+// An approximation of iterator_t for pre-C++20 systems.
+template <typename T>
+using iterator_t = decltype(std::begin(std::declval<T&>()));
+template <typename T> using sentinel_t = decltype(std::end(std::declval<T&>()));
+
+// A workaround for std::string not having mutable data() until C++17.
+template <typename Char> inline Char* get_data(std::basic_string<Char>& s) {
+ return &s[0];
+}
+template <typename Container>
+inline typename Container::value_type* get_data(Container& c) {
+ return c.data();
+}
+
+#if defined(_SECURE_SCL) && _SECURE_SCL
+// Make a checked iterator to avoid MSVC warnings.
+template <typename T> using checked_ptr = stdext::checked_array_iterator<T*>;
+template <typename T> checked_ptr<T> make_checked(T* p, size_t size) {
+ return {p, size};
+}
+#else
+template <typename T> using checked_ptr = T*;
+template <typename T> inline T* make_checked(T* p, size_t) { return p; }
+#endif
+
+template <typename Container, FMT_ENABLE_IF(is_contiguous<Container>::value)>
+#if FMT_CLANG_VERSION
+__attribute__((no_sanitize("undefined")))
+#endif
+inline checked_ptr<typename Container::value_type>
+reserve(std::back_insert_iterator<Container> it, size_t n) {
+ Container& c = get_container(it);
+ size_t size = c.size();
+ c.resize(size + n);
+ return make_checked(get_data(c) + size, n);
+}
+
+template <typename T>
+inline buffer_appender<T> reserve(buffer_appender<T> it, size_t n) {
+ buffer<T>& buf = get_container(it);
+ buf.try_reserve(buf.size() + n);
+ return it;
+}
+
+template <typename Iterator> inline Iterator& reserve(Iterator& it, size_t) {
+ return it;
+}
+
+template <typename T, typename OutputIt>
+constexpr T* to_pointer(OutputIt, size_t) {
+ return nullptr;
+}
+template <typename T> T* to_pointer(buffer_appender<T> it, size_t n) {
+ buffer<T>& buf = get_container(it);
+ auto size = buf.size();
+ if (buf.capacity() < size + n) return nullptr;
+ buf.try_resize(size + n);
+ return buf.data() + size;
+}
+
+template <typename Container, FMT_ENABLE_IF(is_contiguous<Container>::value)>
+inline std::back_insert_iterator<Container> base_iterator(
+ std::back_insert_iterator<Container>& it,
+ checked_ptr<typename Container::value_type>) {
+ return it;
+}
+
+template <typename Iterator>
+inline Iterator base_iterator(Iterator, Iterator it) {
+ return it;
+}
+
+// An output iterator that counts the number of objects written to it and
+// discards them.
+class counting_iterator {
+ private:
+ size_t count_;
+
+ public:
+ using iterator_category = std::output_iterator_tag;
+ using difference_type = std::ptrdiff_t;
+ using pointer = void;
+ using reference = void;
+ using _Unchecked_type = counting_iterator; // Mark iterator as checked.
+
+ struct value_type {
+ template <typename T> void operator=(const T&) {}
+ };
+
+ counting_iterator() : count_(0) {}
+
+ size_t count() const { return count_; }
+
+ counting_iterator& operator++() {
+ ++count_;
+ return *this;
+ }
+ counting_iterator operator++(int) {
+ auto it = *this;
+ ++*this;
+ return it;
+ }
+
+ friend counting_iterator operator+(counting_iterator it, difference_type n) {
+ it.count_ += static_cast<size_t>(n);
+ return it;
+ }
+
+ value_type operator*() const { return {}; }
+};
+
+template <typename OutputIt> class truncating_iterator_base {
+ protected:
+ OutputIt out_;
+ size_t limit_;
+ size_t count_;
+
+ truncating_iterator_base(OutputIt out, size_t limit)
+ : out_(out), limit_(limit), count_(0) {}
+
+ public:
+ using iterator_category = std::output_iterator_tag;
+ using value_type = typename std::iterator_traits<OutputIt>::value_type;
+ using difference_type = void;
+ using pointer = void;
+ using reference = void;
+ using _Unchecked_type =
+ truncating_iterator_base; // Mark iterator as checked.
+
+ OutputIt base() const { return out_; }
+ size_t count() const { return count_; }
+};
+
+// An output iterator that truncates the output and counts the number of objects
+// written to it.
+template <typename OutputIt,
+ typename Enable = typename std::is_void<
+ typename std::iterator_traits<OutputIt>::value_type>::type>
+class truncating_iterator;
+
+template <typename OutputIt>
+class truncating_iterator<OutputIt, std::false_type>
+ : public truncating_iterator_base<OutputIt> {
+ mutable typename truncating_iterator_base<OutputIt>::value_type blackhole_;
+
+ public:
+ using value_type = typename truncating_iterator_base<OutputIt>::value_type;
+
+ truncating_iterator(OutputIt out, size_t limit)
+ : truncating_iterator_base<OutputIt>(out, limit) {}
+
+ truncating_iterator& operator++() {
+ if (this->count_++ < this->limit_) ++this->out_;
+ return *this;
+ }
+
+ truncating_iterator operator++(int) {
+ auto it = *this;
+ ++*this;
+ return it;
+ }
+
+ value_type& operator*() const {
+ return this->count_ < this->limit_ ? *this->out_ : blackhole_;
+ }
+};
+
+template <typename OutputIt>
+class truncating_iterator<OutputIt, std::true_type>
+ : public truncating_iterator_base<OutputIt> {
+ public:
+ truncating_iterator(OutputIt out, size_t limit)
+ : truncating_iterator_base<OutputIt>(out, limit) {}
+
+ template <typename T> truncating_iterator& operator=(T val) {
+ if (this->count_++ < this->limit_) *this->out_++ = val;
+ return *this;
+ }
+
+ truncating_iterator& operator++() { return *this; }
+ truncating_iterator& operator++(int) { return *this; }
+ truncating_iterator& operator*() { return *this; }
+};
+
+template <typename Char>
+inline size_t count_code_points(basic_string_view<Char> s) {
+ return s.size();
+}
+
+// Counts the number of code points in a UTF-8 string.
+inline size_t count_code_points(basic_string_view<char> s) {
+ const char* data = s.data();
+ size_t num_code_points = 0;
+ for (size_t i = 0, size = s.size(); i != size; ++i) {
+ if ((data[i] & 0xc0) != 0x80) ++num_code_points;
+ }
+ return num_code_points;
+}
+
+inline size_t count_code_points(basic_string_view<char8_type> s) {
+ return count_code_points(basic_string_view<char>(
+ reinterpret_cast<const char*>(s.data()), s.size()));
+}
+
+template <typename Char>
+inline size_t code_point_index(basic_string_view<Char> s, size_t n) {
+ size_t size = s.size();
+ return n < size ? n : size;
+}
+
+// Calculates the index of the nth code point in a UTF-8 string.
+inline size_t code_point_index(basic_string_view<char8_type> s, size_t n) {
+ const char8_type* data = s.data();
+ size_t num_code_points = 0;
+ for (size_t i = 0, size = s.size(); i != size; ++i) {
+ if ((data[i] & 0xc0) != 0x80 && ++num_code_points > n) {
+ return i;
+ }
+ }
+ return s.size();
+}
+
+template <typename InputIt, typename OutChar>
+using needs_conversion = bool_constant<
+ std::is_same<typename std::iterator_traits<InputIt>::value_type,
+ char>::value &&
+ std::is_same<OutChar, char8_type>::value>;
+
+template <typename OutChar, typename InputIt, typename OutputIt,
+ FMT_ENABLE_IF(!needs_conversion<InputIt, OutChar>::value)>
+OutputIt copy_str(InputIt begin, InputIt end, OutputIt it) {
+ return std::copy(begin, end, it);
+}
+
+template <typename OutChar, typename InputIt, typename OutputIt,
+ FMT_ENABLE_IF(needs_conversion<InputIt, OutChar>::value)>
+OutputIt copy_str(InputIt begin, InputIt end, OutputIt it) {
+ return std::transform(begin, end, it,
+ [](char c) { return static_cast<char8_type>(c); });
+}
+
+template <typename Char, typename InputIt>
+inline counting_iterator copy_str(InputIt begin, InputIt end,
+ counting_iterator it) {
+ return it + (end - begin);
+}
+
+template <typename T>
+using is_fast_float = bool_constant<std::numeric_limits<T>::is_iec559 &&
+ sizeof(T) <= sizeof(double)>;
+
+#ifndef FMT_USE_FULL_CACHE_DRAGONBOX
+# define FMT_USE_FULL_CACHE_DRAGONBOX 0
+#endif
+
+template <typename T>
+template <typename U>
+void buffer<T>::append(const U* begin, const U* end) {
+ do {
+ auto count = to_unsigned(end - begin);
+ try_reserve(size_ + count);
+ auto free_cap = capacity_ - size_;
+ if (free_cap < count) count = free_cap;
+ std::uninitialized_copy_n(begin, count, make_checked(ptr_ + size_, count));
+ size_ += count;
+ begin += count;
+ } while (begin != end);
+}
+
+template <typename OutputIt, typename T, typename Traits>
+void iterator_buffer<OutputIt, T, Traits>::flush() {
+ out_ = std::copy_n(data_, this->limit(this->size()), out_);
+ this->clear();
+}
+} // namespace detail
+
+// The number of characters to store in the basic_memory_buffer object itself
+// to avoid dynamic memory allocation.
+enum { inline_buffer_size = 500 };
+
+/**
+ \rst
+ A dynamically growing memory buffer for trivially copyable/constructible types
+ with the first ``SIZE`` elements stored in the object itself.
+
+ You can use one of the following type aliases for common character types:
+
+ +----------------+------------------------------+
+ | Type | Definition |
+ +================+==============================+
+ | memory_buffer | basic_memory_buffer<char> |
+ +----------------+------------------------------+
+ | wmemory_buffer | basic_memory_buffer<wchar_t> |
+ +----------------+------------------------------+
+
+ **Example**::
+
+ fmt::memory_buffer out;
+ format_to(out, "The answer is {}.", 42);
+
+ This will append the following output to the ``out`` object:
+
+ .. code-block:: none
+
+ The answer is 42.
+
+ The output can be converted to an ``std::string`` with ``to_string(out)``.
+ \endrst
+ */
+template <typename T, size_t SIZE = inline_buffer_size,
+ typename Allocator = std::allocator<T>>
+class basic_memory_buffer final : public detail::buffer<T> {
+ private:
+ T store_[SIZE];
+
+ // Don't inherit from Allocator avoid generating type_info for it.
+ Allocator alloc_;
+
+ // Deallocate memory allocated by the buffer.
+ void deallocate() {
+ T* data = this->data();
+ if (data != store_) alloc_.deallocate(data, this->capacity());
+ }
+
+ protected:
+ void grow(size_t size) final FMT_OVERRIDE;
+
+ public:
+ using value_type = T;
+ using const_reference = const T&;
+
+ explicit basic_memory_buffer(const Allocator& alloc = Allocator())
+ : alloc_(alloc) {
+ this->set(store_, SIZE);
+ }
+ ~basic_memory_buffer() { deallocate(); }
+
+ private:
+ // Move data from other to this buffer.
+ void move(basic_memory_buffer& other) {
+ alloc_ = std::move(other.alloc_);
+ T* data = other.data();
+ size_t size = other.size(), capacity = other.capacity();
+ if (data == other.store_) {
+ this->set(store_, capacity);
+ std::uninitialized_copy(other.store_, other.store_ + size,
+ detail::make_checked(store_, capacity));
+ } else {
+ this->set(data, capacity);
+ // Set pointer to the inline array so that delete is not called
+ // when deallocating.
+ other.set(other.store_, 0);
+ }
+ this->resize(size);
+ }
+
+ public:
+ /**
+ \rst
+ Constructs a :class:`fmt::basic_memory_buffer` object moving the content
+ of the other object to it.
+ \endrst
+ */
+ basic_memory_buffer(basic_memory_buffer&& other) FMT_NOEXCEPT { move(other); }
+
+ /**
+ \rst
+ Moves the content of the other ``basic_memory_buffer`` object to this one.
+ \endrst
+ */
+ basic_memory_buffer& operator=(basic_memory_buffer&& other) FMT_NOEXCEPT {
+ FMT_ASSERT(this != &other, "");
+ deallocate();
+ move(other);
+ return *this;
+ }
+
+ // Returns a copy of the allocator associated with this buffer.
+ Allocator get_allocator() const { return alloc_; }
+
+ /**
+ Resizes the buffer to contain *count* elements. If T is a POD type new
+ elements may not be initialized.
+ */
+ void resize(size_t count) { this->try_resize(count); }
+
+ /** Increases the buffer capacity to *new_capacity*. */
+ void reserve(size_t new_capacity) { this->try_reserve(new_capacity); }
+
+ // Directly append data into the buffer
+ using detail::buffer<T>::append;
+ template <typename ContiguousRange>
+ void append(const ContiguousRange& range) {
+ append(range.data(), range.data() + range.size());
+ }
+};
+
+template <typename T, size_t SIZE, typename Allocator>
+void basic_memory_buffer<T, SIZE, Allocator>::grow(size_t size) {
+#ifdef FMT_FUZZ
+ if (size > 5000) throw std::runtime_error("fuzz mode - won't grow that much");
+#endif
+ size_t old_capacity = this->capacity();
+ size_t new_capacity = old_capacity + old_capacity / 2;
+ if (size > new_capacity) new_capacity = size;
+ T* old_data = this->data();
+ T* new_data =
+ std::allocator_traits<Allocator>::allocate(alloc_, new_capacity);
+ // The following code doesn't throw, so the raw pointer above doesn't leak.
+ std::uninitialized_copy(old_data, old_data + this->size(),
+ detail::make_checked(new_data, new_capacity));
+ this->set(new_data, new_capacity);
+ // deallocate must not throw according to the standard, but even if it does,
+ // the buffer already uses the new storage and will deallocate it in
+ // destructor.
+ if (old_data != store_) alloc_.deallocate(old_data, old_capacity);
+}
+
+using memory_buffer = basic_memory_buffer<char>;
+using wmemory_buffer = basic_memory_buffer<wchar_t>;
+
+template <typename T, size_t SIZE, typename Allocator>
+struct is_contiguous<basic_memory_buffer<T, SIZE, Allocator>> : std::true_type {
+};
+
+/** A formatting error such as invalid format string. */
+FMT_CLASS_API
+class FMT_API format_error : public std::runtime_error {
+ public:
+ explicit format_error(const char* message) : std::runtime_error(message) {}
+ explicit format_error(const std::string& message)
+ : std::runtime_error(message) {}
+ format_error(const format_error&) = default;
+ format_error& operator=(const format_error&) = default;
+ format_error(format_error&&) = default;
+ format_error& operator=(format_error&&) = default;
+ ~format_error() FMT_NOEXCEPT FMT_OVERRIDE;
+};
+
+namespace detail {
+
+template <typename T>
+using is_signed =
+ std::integral_constant<bool, std::numeric_limits<T>::is_signed ||
+ std::is_same<T, int128_t>::value>;
+
+// Returns true if value is negative, false otherwise.
+// Same as `value < 0` but doesn't produce warnings if T is an unsigned type.
+template <typename T, FMT_ENABLE_IF(is_signed<T>::value)>
+FMT_CONSTEXPR bool is_negative(T value) {
+ return value < 0;
+}
+template <typename T, FMT_ENABLE_IF(!is_signed<T>::value)>
+FMT_CONSTEXPR bool is_negative(T) {
+ return false;
+}
+
+template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+FMT_CONSTEXPR bool is_supported_floating_point(T) {
+ return (std::is_same<T, float>::value && FMT_USE_FLOAT) ||
+ (std::is_same<T, double>::value && FMT_USE_DOUBLE) ||
+ (std::is_same<T, long double>::value && FMT_USE_LONG_DOUBLE);
+}
+
+// Smallest of uint32_t, uint64_t, uint128_t that is large enough to
+// represent all values of an integral type T.
+template <typename T>
+using uint32_or_64_or_128_t =
+ conditional_t<num_bits<T>() <= 32 && !FMT_REDUCE_INT_INSTANTIATIONS,
+ uint32_t,
+ conditional_t<num_bits<T>() <= 64, uint64_t, uint128_t>>;
+
+// 128-bit integer type used internally
+struct FMT_EXTERN_TEMPLATE_API uint128_wrapper {
+ uint128_wrapper() = default;
+
+#if FMT_USE_INT128
+ uint128_t internal_;
+
+ uint128_wrapper(uint64_t high, uint64_t low) FMT_NOEXCEPT
+ : internal_{static_cast<uint128_t>(low) |
+ (static_cast<uint128_t>(high) << 64)} {}
+
+ uint128_wrapper(uint128_t u) : internal_{u} {}
+
+ uint64_t high() const FMT_NOEXCEPT { return uint64_t(internal_ >> 64); }
+ uint64_t low() const FMT_NOEXCEPT { return uint64_t(internal_); }
+
+ uint128_wrapper& operator+=(uint64_t n) FMT_NOEXCEPT {
+ internal_ += n;
+ return *this;
+ }
+#else
+ uint64_t high_;
+ uint64_t low_;
+
+ uint128_wrapper(uint64_t high, uint64_t low) FMT_NOEXCEPT : high_{high},
+ low_{low} {}
+
+ uint64_t high() const FMT_NOEXCEPT { return high_; }
+ uint64_t low() const FMT_NOEXCEPT { return low_; }
+
+ uint128_wrapper& operator+=(uint64_t n) FMT_NOEXCEPT {
+# if defined(_MSC_VER) && defined(_M_X64)
+ unsigned char carry = _addcarry_u64(0, low_, n, &low_);
+ _addcarry_u64(carry, high_, 0, &high_);
+ return *this;
+# else
+ uint64_t sum = low_ + n;
+ high_ += (sum < low_ ? 1 : 0);
+ low_ = sum;
+ return *this;
+# endif
+ }
+#endif
+};
+
+// Table entry type for divisibility test used internally
+template <typename T> struct FMT_EXTERN_TEMPLATE_API divtest_table_entry {
+ T mod_inv;
+ T max_quotient;
+};
+
+// Static data is placed in this class template for the header-only config.
+template <typename T = void> struct FMT_EXTERN_TEMPLATE_API basic_data {
+ static const uint64_t powers_of_10_64[];
+ static const uint32_t zero_or_powers_of_10_32_new[];
+ static const uint64_t zero_or_powers_of_10_64_new[];
+ static const uint64_t grisu_pow10_significands[];
+ static const int16_t grisu_pow10_exponents[];
+ static const divtest_table_entry<uint32_t> divtest_table_for_pow5_32[];
+ static const divtest_table_entry<uint64_t> divtest_table_for_pow5_64[];
+ static const uint64_t dragonbox_pow10_significands_64[];
+ static const uint128_wrapper dragonbox_pow10_significands_128[];
+ // log10(2) = 0x0.4d104d427de7fbcc...
+ static const uint64_t log10_2_significand = 0x4d104d427de7fbcc;
+#if !FMT_USE_FULL_CACHE_DRAGONBOX
+ static const uint64_t powers_of_5_64[];
+ static const uint32_t dragonbox_pow10_recovery_errors[];
+#endif
+ // GCC generates slightly better code for pairs than chars.
+ using digit_pair = char[2];
+ static const digit_pair digits[];
+ static const char hex_digits[];
+ static const char foreground_color[];
+ static const char background_color[];
+ static const char reset_color[5];
+ static const wchar_t wreset_color[5];
+ static const char signs[];
+ static const char left_padding_shifts[5];
+ static const char right_padding_shifts[5];
+
+ // DEPRECATED! These are for ABI compatibility.
+ static const uint32_t zero_or_powers_of_10_32[];
+ static const uint64_t zero_or_powers_of_10_64[];
+};
+
+// Maps bsr(n) to ceil(log10(pow(2, bsr(n) + 1) - 1)).
+// This is a function instead of an array to workaround a bug in GCC10 (#1810).
+FMT_INLINE uint16_t bsr2log10(int bsr) {
+ static constexpr uint16_t data[] = {
+ 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5,
+ 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 9, 9, 9, 10, 10, 10,
+ 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15,
+ 15, 16, 16, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 19, 19, 20};
+ return data[bsr];
+}
+
+#ifndef FMT_EXPORTED
+FMT_EXTERN template struct basic_data<void>;
+#endif
+
+// This is a struct rather than an alias to avoid shadowing warnings in gcc.
+struct data : basic_data<> {};
+
+#ifdef FMT_BUILTIN_CLZLL
+// Returns the number of decimal digits in n. Leading zeros are not counted
+// except for n == 0 in which case count_digits returns 1.
+inline int count_digits(uint64_t n) {
+ // https://github.com/fmtlib/format-benchmark/blob/master/digits10
+ auto t = bsr2log10(FMT_BUILTIN_CLZLL(n | 1) ^ 63);
+ return t - (n < data::zero_or_powers_of_10_64_new[t]);
+}
+#else
+// Fallback version of count_digits used when __builtin_clz is not available.
+inline int count_digits(uint64_t n) {
+ int count = 1;
+ for (;;) {
+ // Integer division is slow so do it for a group of four digits instead
+ // of for every digit. The idea comes from the talk by Alexandrescu
+ // "Three Optimization Tips for C++". See speed-test for a comparison.
+ if (n < 10) return count;
+ if (n < 100) return count + 1;
+ if (n < 1000) return count + 2;
+ if (n < 10000) return count + 3;
+ n /= 10000u;
+ count += 4;
+ }
+}
+#endif
+
+#if FMT_USE_INT128
+inline int count_digits(uint128_t n) {
+ int 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
+
+// Counts the number of digits in n. BITS = log2(radix).
+template <unsigned BITS, typename UInt> inline int count_digits(UInt n) {
+ int num_digits = 0;
+ do {
+ ++num_digits;
+ } while ((n >>= BITS) != 0);
+ return num_digits;
+}
+
+template <> int count_digits<4>(detail::fallback_uintptr n);
+
+#if FMT_GCC_VERSION || FMT_CLANG_VERSION
+# define FMT_ALWAYS_INLINE inline __attribute__((always_inline))
+#elif FMT_MSC_VER
+# define FMT_ALWAYS_INLINE __forceinline
+#else
+# define FMT_ALWAYS_INLINE inline
+#endif
+
+// To suppress unnecessary security cookie checks
+#if FMT_MSC_VER && !FMT_CLANG_VERSION
+# define FMT_SAFEBUFFERS __declspec(safebuffers)
+#else
+# define FMT_SAFEBUFFERS
+#endif
+
+#ifdef FMT_BUILTIN_CLZ
+// Optional version of count_digits for better performance on 32-bit platforms.
+inline int count_digits(uint32_t n) {
+ auto t = bsr2log10(FMT_BUILTIN_CLZ(n | 1) ^ 31);
+ return t - (n < data::zero_or_powers_of_10_32_new[t]);
+}
+#endif
+
+template <typename Int> constexpr int digits10() FMT_NOEXCEPT {
+ return std::numeric_limits<Int>::digits10;
+}
+template <> constexpr int digits10<int128_t>() FMT_NOEXCEPT { return 38; }
+template <> constexpr int digits10<uint128_t>() FMT_NOEXCEPT { return 38; }
+
+template <typename Char> FMT_API std::string grouping_impl(locale_ref loc);
+template <typename Char> inline std::string grouping(locale_ref loc) {
+ return grouping_impl<char>(loc);
+}
+template <> inline std::string grouping<wchar_t>(locale_ref loc) {
+ return grouping_impl<wchar_t>(loc);
+}
+
+template <typename Char> FMT_API Char thousands_sep_impl(locale_ref loc);
+template <typename Char> inline Char thousands_sep(locale_ref loc) {
+ return Char(thousands_sep_impl<char>(loc));
+}
+template <> inline wchar_t thousands_sep(locale_ref loc) {
+ return thousands_sep_impl<wchar_t>(loc);
+}
+
+template <typename Char> FMT_API Char decimal_point_impl(locale_ref loc);
+template <typename Char> inline Char decimal_point(locale_ref loc) {
+ return Char(decimal_point_impl<char>(loc));
+}
+template <> inline wchar_t decimal_point(locale_ref loc) {
+ return decimal_point_impl<wchar_t>(loc);
+}
+
+// Compares two characters for equality.
+template <typename Char> bool equal2(const Char* lhs, const char* rhs) {
+ return lhs[0] == rhs[0] && lhs[1] == rhs[1];
+}
+inline bool equal2(const char* lhs, const char* rhs) {
+ return memcmp(lhs, rhs, 2) == 0;
+}
+
+// Copies two characters from src to dst.
+template <typename Char> void copy2(Char* dst, const char* src) {
+ *dst++ = static_cast<Char>(*src++);
+ *dst = static_cast<Char>(*src);
+}
+FMT_INLINE void copy2(char* dst, const char* src) { memcpy(dst, src, 2); }
+
+template <typename Iterator> struct format_decimal_result {
+ Iterator begin;
+ Iterator end;
+};
+
+// Formats a decimal unsigned integer value writing into out pointing to a
+// buffer of specified size. The caller must ensure that the buffer is large
+// enough.
+template <typename Char, typename UInt>
+inline format_decimal_result<Char*> format_decimal(Char* out, UInt value,
+ int size) {
+ FMT_ASSERT(size >= count_digits(value), "invalid digit count");
+ out += size;
+ Char* end = out;
+ 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.
+ out -= 2;
+ copy2(out, data::digits[value % 100]);
+ value /= 100;
+ }
+ if (value < 10) {
+ *--out = static_cast<Char>('0' + value);
+ return {out, end};
+ }
+ out -= 2;
+ copy2(out, data::digits[value]);
+ return {out, end};
+}
+
+template <typename Char, typename UInt, typename Iterator,
+ FMT_ENABLE_IF(!std::is_pointer<remove_cvref_t<Iterator>>::value)>
+inline format_decimal_result<Iterator> format_decimal(Iterator out, UInt value,
+ int size) {
+ // Buffer is large enough to hold all digits (digits10 + 1).
+ Char buffer[digits10<UInt>() + 1];
+ auto end = format_decimal(buffer, value, size).end;
+ return {out, detail::copy_str<Char>(buffer, end, out)};
+}
+
+template <unsigned BASE_BITS, typename Char, typename UInt>
+inline Char* format_uint(Char* buffer, UInt value, int num_digits,
+ bool upper = false) {
+ buffer += num_digits;
+ Char* end = buffer;
+ do {
+ const char* digits = upper ? "0123456789ABCDEF" : data::hex_digits;
+ unsigned digit = (value & ((1 << BASE_BITS) - 1));
+ *--buffer = static_cast<Char>(BASE_BITS < 4 ? static_cast<char>('0' + digit)
+ : digits[digit]);
+ } while ((value >>= BASE_BITS) != 0);
+ return end;
+}
+
+template <unsigned BASE_BITS, typename Char>
+Char* format_uint(Char* buffer, detail::fallback_uintptr n, int num_digits,
+ bool = false) {
+ auto char_digits = std::numeric_limits<unsigned char>::digits / 4;
+ int start = (num_digits + char_digits - 1) / char_digits - 1;
+ if (int start_digits = num_digits % char_digits) {
+ unsigned value = n.value[start--];
+ buffer = format_uint<BASE_BITS>(buffer, value, start_digits);
+ }
+ for (; start >= 0; --start) {
+ unsigned value = n.value[start];
+ buffer += char_digits;
+ auto p = buffer;
+ for (int i = 0; i < char_digits; ++i) {
+ unsigned digit = (value & ((1 << BASE_BITS) - 1));
+ *--p = static_cast<Char>(data::hex_digits[digit]);
+ value >>= BASE_BITS;
+ }
+ }
+ return buffer;
+}
+
+template <unsigned BASE_BITS, typename Char, typename It, typename UInt>
+inline It format_uint(It out, UInt value, int num_digits, bool upper = false) {
+ if (auto ptr = to_pointer<Char>(out, to_unsigned(num_digits))) {
+ format_uint<BASE_BITS>(ptr, value, num_digits, upper);
+ return out;
+ }
+ // Buffer should be large enough to hold all digits (digits / BASE_BITS + 1).
+ char buffer[num_bits<UInt>() / BASE_BITS + 1];
+ format_uint<BASE_BITS>(buffer, value, num_digits, upper);
+ return detail::copy_str<Char>(buffer, buffer + num_digits, out);
+}
+
+// A converter from UTF-8 to UTF-16.
+class utf8_to_utf16 {
+ private:
+ wmemory_buffer buffer_;
+
+ public:
+ FMT_API explicit utf8_to_utf16(string_view s);
+ operator wstring_view() const { return {&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 {&buffer_[0], size()}; }
+};
+
+template <typename T = void> struct null {};
+
+// Workaround an array initialization issue in gcc 4.8.
+template <typename Char> struct fill_t {
+ private:
+ enum { max_size = 4 };
+ Char data_[max_size] = {Char(' '), Char(0), Char(0), Char(0)};
+ unsigned char size_ = 1;
+
+ public:
+ FMT_CONSTEXPR void operator=(basic_string_view<Char> s) {
+ auto size = s.size();
+ if (size > max_size) {
+ FMT_THROW(format_error("invalid fill"));
+ return;
+ }
+ for (size_t i = 0; i < size; ++i) data_[i] = s[i];
+ size_ = static_cast<unsigned char>(size);
+ }
+
+ size_t size() const { return size_; }
+ const Char* data() const { return data_; }
+
+ FMT_CONSTEXPR Char& operator[](size_t index) { return data_[index]; }
+ FMT_CONSTEXPR const Char& operator[](size_t index) const {
+ return data_[index];
+ }
+};
+} // namespace detail
+
+// We cannot use enum classes as bit fields because of a gcc bug
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61414.
+namespace align {
+enum type { none, left, right, center, numeric };
+}
+using align_t = align::type;
+
+namespace sign {
+enum type { none, minus, plus, space };
+}
+using sign_t = sign::type;
+
+// Format specifiers for built-in and string types.
+template <typename Char> struct basic_format_specs {
+ int width;
+ int precision;
+ char type;
+ align_t align : 4;
+ sign_t sign : 3;
+ bool alt : 1; // Alternate form ('#').
+ detail::fill_t<Char> fill;
+
+ constexpr basic_format_specs()
+ : width(0),
+ precision(-1),
+ type(0),
+ align(align::none),
+ sign(sign::none),
+ alt(false) {}
+};
+
+using format_specs = basic_format_specs<char>;
+
+namespace detail {
+namespace dragonbox {
+
+// Type-specific information that Dragonbox uses.
+template <class T> struct float_info;
+
+template <> struct float_info<float> {
+ using carrier_uint = uint32_t;
+ static const int significand_bits = 23;
+ static const int exponent_bits = 8;
+ static const int min_exponent = -126;
+ static const int max_exponent = 127;
+ static const int exponent_bias = -127;
+ static const int decimal_digits = 9;
+ static const int kappa = 1;
+ static const int big_divisor = 100;
+ static const int small_divisor = 10;
+ static const int min_k = -31;
+ static const int max_k = 46;
+ static const int cache_bits = 64;
+ static const int divisibility_check_by_5_threshold = 39;
+ static const int case_fc_pm_half_lower_threshold = -1;
+ static const int case_fc_pm_half_upper_threshold = 6;
+ static const int case_fc_lower_threshold = -2;
+ static const int case_fc_upper_threshold = 6;
+ static const int case_shorter_interval_left_endpoint_lower_threshold = 2;
+ static const int case_shorter_interval_left_endpoint_upper_threshold = 3;
+ static const int shorter_interval_tie_lower_threshold = -35;
+ static const int shorter_interval_tie_upper_threshold = -35;
+ static const int max_trailing_zeros = 7;
+};
+
+template <> struct float_info<double> {
+ using carrier_uint = uint64_t;
+ static const int significand_bits = 52;
+ static const int exponent_bits = 11;
+ static const int min_exponent = -1022;
+ static const int max_exponent = 1023;
+ static const int exponent_bias = -1023;
+ static const int decimal_digits = 17;
+ static const int kappa = 2;
+ static const int big_divisor = 1000;
+ static const int small_divisor = 100;
+ static const int min_k = -292;
+ static const int max_k = 326;
+ static const int cache_bits = 128;
+ static const int divisibility_check_by_5_threshold = 86;
+ static const int case_fc_pm_half_lower_threshold = -2;
+ static const int case_fc_pm_half_upper_threshold = 9;
+ static const int case_fc_lower_threshold = -4;
+ static const int case_fc_upper_threshold = 9;
+ static const int case_shorter_interval_left_endpoint_lower_threshold = 2;
+ static const int case_shorter_interval_left_endpoint_upper_threshold = 3;
+ static const int shorter_interval_tie_lower_threshold = -77;
+ static const int shorter_interval_tie_upper_threshold = -77;
+ static const int max_trailing_zeros = 16;
+};
+
+template <typename T> struct decimal_fp {
+ using significand_type = typename float_info<T>::carrier_uint;
+ significand_type significand;
+ int exponent;
+};
+
+template <typename T> FMT_API decimal_fp<T> to_decimal(T x) FMT_NOEXCEPT;
+} // namespace dragonbox
+
+template <typename T>
+constexpr typename dragonbox::float_info<T>::carrier_uint exponent_mask() {
+ using uint = typename dragonbox::float_info<T>::carrier_uint;
+ return ((uint(1) << dragonbox::float_info<T>::exponent_bits) - 1)
+ << dragonbox::float_info<T>::significand_bits;
+}
+
+// A floating-point presentation format.
+enum class float_format : unsigned char {
+ general, // General: exponent notation or fixed point based on magnitude.
+ exp, // Exponent notation with the default precision of 6, e.g. 1.2e-3.
+ fixed, // Fixed point with the default precision of 6, e.g. 0.0012.
+ hex
+};
+
+struct float_specs {
+ int precision;
+ float_format format : 8;
+ sign_t sign : 8;
+ bool upper : 1;
+ bool locale : 1;
+ bool binary32 : 1;
+ bool use_grisu : 1;
+ bool showpoint : 1;
+};
+
+// Writes the exponent exp in the form "[+-]d{2,3}" to buffer.
+template <typename Char, typename It> It write_exponent(int exp, It it) {
+ FMT_ASSERT(-10000 < exp && exp < 10000, "exponent out of range");
+ if (exp < 0) {
+ *it++ = static_cast<Char>('-');
+ exp = -exp;
+ } else {
+ *it++ = static_cast<Char>('+');
+ }
+ if (exp >= 100) {
+ const char* top = data::digits[exp / 100];
+ if (exp >= 1000) *it++ = static_cast<Char>(top[0]);
+ *it++ = static_cast<Char>(top[1]);
+ exp %= 100;
+ }
+ const char* d = data::digits[exp];
+ *it++ = static_cast<Char>(d[0]);
+ *it++ = static_cast<Char>(d[1]);
+ return it;
+}
+
+template <typename T>
+int format_float(T value, int precision, float_specs specs, buffer<char>& buf);
+
+// Formats a floating-point number with snprintf.
+template <typename T>
+int snprintf_float(T value, int precision, float_specs specs,
+ buffer<char>& buf);
+
+template <typename T> T promote_float(T value) { return value; }
+inline double promote_float(float value) { return static_cast<double>(value); }
+
+template <typename Handler>
+FMT_CONSTEXPR void handle_int_type_spec(char spec, Handler&& handler) {
+ switch (spec) {
+ case 0:
+ case 'd':
+ handler.on_dec();
+ break;
+ case 'x':
+ case 'X':
+ handler.on_hex();
+ break;
+ case 'b':
+ case 'B':
+ handler.on_bin();
+ break;
+ case 'o':
+ handler.on_oct();
+ break;
+#ifdef FMT_DEPRECATED_N_SPECIFIER
+ case 'n':
+#endif
+ case 'L':
+ handler.on_num();
+ break;
+ case 'c':
+ handler.on_chr();
+ break;
+ default:
+ handler.on_error();
+ }
+}
+
+template <typename ErrorHandler = error_handler, typename Char>
+FMT_CONSTEXPR float_specs parse_float_type_spec(
+ const basic_format_specs<Char>& specs, ErrorHandler&& eh = {}) {
+ auto result = float_specs();
+ result.showpoint = specs.alt;
+ switch (specs.type) {
+ case 0:
+ result.format = float_format::general;
+ result.showpoint |= specs.precision > 0;
+ break;
+ case 'G':
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case 'g':
+ result.format = float_format::general;
+ break;
+ case 'E':
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case 'e':
+ result.format = float_format::exp;
+ result.showpoint |= specs.precision != 0;
+ break;
+ case 'F':
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case 'f':
+ result.format = float_format::fixed;
+ result.showpoint |= specs.precision != 0;
+ break;
+ case 'A':
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case 'a':
+ result.format = float_format::hex;
+ break;
+#ifdef FMT_DEPRECATED_N_SPECIFIER
+ case 'n':
+#endif
+ case 'L':
+ result.locale = true;
+ break;
+ default:
+ eh.on_error("invalid type specifier");
+ break;
+ }
+ return result;
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_char_specs(const basic_format_specs<Char>* specs,
+ Handler&& handler) {
+ if (!specs) return handler.on_char();
+ if (specs->type && specs->type != 'c') return handler.on_int();
+ if (specs->align == align::numeric || specs->sign != sign::none || specs->alt)
+ handler.on_error("invalid format specifier for char");
+ handler.on_char();
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR void handle_cstring_type_spec(Char spec, Handler&& handler) {
+ if (spec == 0 || spec == 's')
+ handler.on_string();
+ else if (spec == 'p')
+ handler.on_pointer();
+ else
+ handler.on_error("invalid type specifier");
+}
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void check_string_type_spec(Char spec, ErrorHandler&& eh) {
+ if (spec != 0 && spec != 's') eh.on_error("invalid type specifier");
+}
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void check_pointer_type_spec(Char spec, ErrorHandler&& eh) {
+ if (spec != 0 && spec != 'p') eh.on_error("invalid type specifier");
+}
+
+template <typename ErrorHandler> class int_type_checker : private ErrorHandler {
+ public:
+ FMT_CONSTEXPR explicit int_type_checker(ErrorHandler eh) : ErrorHandler(eh) {}
+
+ FMT_CONSTEXPR void on_dec() {}
+ FMT_CONSTEXPR void on_hex() {}
+ FMT_CONSTEXPR void on_bin() {}
+ FMT_CONSTEXPR void on_oct() {}
+ FMT_CONSTEXPR void on_num() {}
+ FMT_CONSTEXPR void on_chr() {}
+
+ FMT_CONSTEXPR void on_error() {
+ ErrorHandler::on_error("invalid type specifier");
+ }
+};
+
+template <typename ErrorHandler>
+class char_specs_checker : public ErrorHandler {
+ private:
+ char type_;
+
+ public:
+ FMT_CONSTEXPR char_specs_checker(char type, ErrorHandler eh)
+ : ErrorHandler(eh), type_(type) {}
+
+ FMT_CONSTEXPR void on_int() {
+ handle_int_type_spec(type_, int_type_checker<ErrorHandler>(*this));
+ }
+ FMT_CONSTEXPR void on_char() {}
+};
+
+template <typename ErrorHandler>
+class cstring_type_checker : public ErrorHandler {
+ public:
+ FMT_CONSTEXPR explicit cstring_type_checker(ErrorHandler eh)
+ : ErrorHandler(eh) {}
+
+ FMT_CONSTEXPR void on_string() {}
+ FMT_CONSTEXPR void on_pointer() {}
+};
+
+template <typename OutputIt, typename Char>
+FMT_NOINLINE OutputIt fill(OutputIt it, size_t n, const fill_t<Char>& fill) {
+ auto fill_size = fill.size();
+ if (fill_size == 1) return std::fill_n(it, n, fill[0]);
+ for (size_t i = 0; i < n; ++i) it = std::copy_n(fill.data(), fill_size, it);
+ return it;
+}
+
+// Writes the output of f, padded according to format specifications in specs.
+// size: output size in code units.
+// width: output display width in (terminal) column positions.
+template <align::type align = align::left, typename OutputIt, typename Char,
+ typename F>
+inline OutputIt write_padded(OutputIt out,
+ const basic_format_specs<Char>& specs, size_t size,
+ size_t width, F&& f) {
+ static_assert(align == align::left || align == align::right, "");
+ unsigned spec_width = to_unsigned(specs.width);
+ size_t padding = spec_width > width ? spec_width - width : 0;
+ auto* shifts = align == align::left ? data::left_padding_shifts
+ : data::right_padding_shifts;
+ size_t left_padding = padding >> shifts[specs.align];
+ auto it = reserve(out, size + padding * specs.fill.size());
+ it = fill(it, left_padding, specs.fill);
+ it = f(it);
+ it = fill(it, padding - left_padding, specs.fill);
+ return base_iterator(out, it);
+}
+
+template <align::type align = align::left, typename OutputIt, typename Char,
+ typename F>
+inline OutputIt write_padded(OutputIt out,
+ const basic_format_specs<Char>& specs, size_t size,
+ F&& f) {
+ return write_padded<align>(out, specs, size, size, f);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write_bytes(OutputIt out, string_view bytes,
+ const basic_format_specs<Char>& specs) {
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ return write_padded(out, specs, bytes.size(), [bytes](iterator it) {
+ const char* data = bytes.data();
+ return copy_str<Char>(data, data + bytes.size(), it);
+ });
+}
+
+// Data for write_int that doesn't depend on output iterator type. It is used to
+// avoid template code bloat.
+template <typename Char> struct write_int_data {
+ size_t size;
+ size_t padding;
+
+ write_int_data(int num_digits, string_view prefix,
+ const basic_format_specs<Char>& specs)
+ : size(prefix.size() + to_unsigned(num_digits)), padding(0) {
+ if (specs.align == align::numeric) {
+ auto width = to_unsigned(specs.width);
+ if (width > size) {
+ padding = width - size;
+ size = width;
+ }
+ } else if (specs.precision > num_digits) {
+ size = prefix.size() + to_unsigned(specs.precision);
+ padding = to_unsigned(specs.precision - num_digits);
+ }
+ }
+};
+
+// Writes an integer in the format
+// <left-padding><prefix><numeric-padding><digits><right-padding>
+// where <digits> are written by f(it).
+template <typename OutputIt, typename Char, typename F>
+OutputIt write_int(OutputIt out, int num_digits, string_view prefix,
+ const basic_format_specs<Char>& specs, F f) {
+ auto data = write_int_data<Char>(num_digits, prefix, specs);
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ return write_padded<align::right>(out, specs, data.size, [=](iterator it) {
+ if (prefix.size() != 0)
+ it = copy_str<Char>(prefix.begin(), prefix.end(), it);
+ it = std::fill_n(it, data.padding, static_cast<Char>('0'));
+ return f(it);
+ });
+}
+
+template <typename StrChar, typename Char, typename OutputIt>
+OutputIt write(OutputIt out, basic_string_view<StrChar> s,
+ const basic_format_specs<Char>& specs) {
+ auto data = s.data();
+ auto size = s.size();
+ if (specs.precision >= 0 && to_unsigned(specs.precision) < size)
+ size = code_point_index(s, to_unsigned(specs.precision));
+ auto width = specs.width != 0
+ ? count_code_points(basic_string_view<StrChar>(data, size))
+ : 0;
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ return write_padded(out, specs, size, width, [=](iterator it) {
+ return copy_str<Char>(data, data + size, it);
+ });
+}
+
+// The handle_int_type_spec handler that writes an integer.
+template <typename OutputIt, typename Char, typename UInt> struct int_writer {
+ OutputIt out;
+ locale_ref locale;
+ const basic_format_specs<Char>& specs;
+ UInt abs_value;
+ char prefix[4];
+ unsigned prefix_size;
+
+ using iterator =
+ remove_reference_t<decltype(reserve(std::declval<OutputIt&>(), 0))>;
+
+ string_view get_prefix() const { return string_view(prefix, prefix_size); }
+
+ template <typename Int>
+ int_writer(OutputIt output, locale_ref loc, Int value,
+ const basic_format_specs<Char>& s)
+ : out(output),
+ locale(loc),
+ specs(s),
+ abs_value(static_cast<UInt>(value)),
+ prefix_size(0) {
+ static_assert(std::is_same<uint32_or_64_or_128_t<Int>, UInt>::value, "");
+ if (is_negative(value)) {
+ prefix[0] = '-';
+ ++prefix_size;
+ abs_value = 0 - abs_value;
+ } else if (specs.sign != sign::none && specs.sign != sign::minus) {
+ prefix[0] = specs.sign == sign::plus ? '+' : ' ';
+ ++prefix_size;
+ }
+ }
+
+ void on_dec() {
+ auto num_digits = count_digits(abs_value);
+ out = write_int(
+ out, num_digits, get_prefix(), specs, [this, num_digits](iterator it) {
+ return format_decimal<Char>(it, abs_value, num_digits).end;
+ });
+ }
+
+ void on_hex() {
+ if (specs.alt) {
+ prefix[prefix_size++] = '0';
+ prefix[prefix_size++] = specs.type;
+ }
+ int num_digits = count_digits<4>(abs_value);
+ out = write_int(out, num_digits, get_prefix(), specs,
+ [this, num_digits](iterator it) {
+ return format_uint<4, Char>(it, abs_value, num_digits,
+ specs.type != 'x');
+ });
+ }
+
+ void on_bin() {
+ if (specs.alt) {
+ prefix[prefix_size++] = '0';
+ prefix[prefix_size++] = static_cast<char>(specs.type);
+ }
+ int num_digits = count_digits<1>(abs_value);
+ out = write_int(out, num_digits, get_prefix(), specs,
+ [this, num_digits](iterator it) {
+ return format_uint<1, Char>(it, abs_value, num_digits);
+ });
+ }
+
+ void on_oct() {
+ int num_digits = count_digits<3>(abs_value);
+ if (specs.alt && specs.precision <= num_digits && abs_value != 0) {
+ // Octal prefix '0' is counted as a digit, so only add it if precision
+ // is not greater than the number of digits.
+ prefix[prefix_size++] = '0';
+ }
+ out = write_int(out, num_digits, get_prefix(), specs,
+ [this, num_digits](iterator it) {
+ return format_uint<3, Char>(it, abs_value, num_digits);
+ });
+ }
+
+ enum { sep_size = 1 };
+
+ void on_num() {
+ std::string groups = grouping<Char>(locale);
+ if (groups.empty()) return on_dec();
+ auto sep = thousands_sep<Char>(locale);
+ if (!sep) return on_dec();
+ int num_digits = count_digits(abs_value);
+ int size = num_digits, n = num_digits;
+ std::string::const_iterator group = groups.cbegin();
+ while (group != groups.cend() && n > *group && *group > 0 &&
+ *group != max_value<char>()) {
+ size += sep_size;
+ n -= *group;
+ ++group;
+ }
+ if (group == groups.cend()) size += sep_size * ((n - 1) / groups.back());
+ char digits[40];
+ format_decimal(digits, abs_value, num_digits);
+ basic_memory_buffer<Char> buffer;
+ size += static_cast<int>(prefix_size);
+ const auto usize = to_unsigned(size);
+ buffer.resize(usize);
+ basic_string_view<Char> s(&sep, sep_size);
+ // Index of a decimal digit with the least significant digit having index 0.
+ int digit_index = 0;
+ group = groups.cbegin();
+ auto p = buffer.data() + size - 1;
+ for (int i = num_digits - 1; i > 0; --i) {
+ *p-- = static_cast<Char>(digits[i]);
+ if (*group <= 0 || ++digit_index % *group != 0 ||
+ *group == max_value<char>())
+ continue;
+ if (group + 1 != groups.cend()) {
+ digit_index = 0;
+ ++group;
+ }
+ std::uninitialized_copy(s.data(), s.data() + s.size(),
+ make_checked(p, s.size()));
+ p -= s.size();
+ }
+ *p-- = static_cast<Char>(*digits);
+ if (prefix_size != 0) *p = static_cast<Char>('-');
+ auto data = buffer.data();
+ out = write_padded<align::right>(
+ out, specs, usize, usize,
+ [=](iterator it) { return copy_str<Char>(data, data + size, it); });
+ }
+
+ void on_chr() { *out++ = static_cast<Char>(abs_value); }
+
+ FMT_NORETURN void on_error() {
+ FMT_THROW(format_error("invalid type specifier"));
+ }
+};
+
+template <typename Char, typename OutputIt>
+OutputIt write_nonfinite(OutputIt out, bool isinf,
+ const basic_format_specs<Char>& specs,
+ const float_specs& fspecs) {
+ auto str =
+ isinf ? (fspecs.upper ? "INF" : "inf") : (fspecs.upper ? "NAN" : "nan");
+ constexpr size_t str_size = 3;
+ auto sign = fspecs.sign;
+ auto size = str_size + (sign ? 1 : 0);
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ return write_padded(out, specs, size, [=](iterator it) {
+ if (sign) *it++ = static_cast<Char>(data::signs[sign]);
+ return copy_str<Char>(str, str + str_size, it);
+ });
+}
+
+// A decimal floating-point number significand * pow(10, exp).
+struct big_decimal_fp {
+ const char* significand;
+ int significand_size;
+ int exponent;
+};
+
+inline int get_significand_size(const big_decimal_fp& fp) {
+ return fp.significand_size;
+}
+template <typename T>
+inline int get_significand_size(const dragonbox::decimal_fp<T>& fp) {
+ return count_digits(fp.significand);
+}
+
+template <typename Char, typename OutputIt>
+inline OutputIt write_significand(OutputIt out, const char* significand,
+ int& significand_size) {
+ return copy_str<Char>(significand, significand + significand_size, out);
+}
+template <typename Char, typename OutputIt, typename UInt>
+inline OutputIt write_significand(OutputIt out, UInt significand,
+ int significand_size) {
+ return format_decimal<Char>(out, significand, significand_size).end;
+}
+
+template <typename Char, typename UInt,
+ FMT_ENABLE_IF(std::is_integral<UInt>::value)>
+inline Char* write_significand(Char* out, UInt significand,
+ int significand_size, int integral_size,
+ Char decimal_point) {
+ if (!decimal_point)
+ return format_decimal(out, significand, significand_size).end;
+ auto end = format_decimal(out + 1, significand, significand_size).end;
+ if (integral_size == 1)
+ out[0] = out[1];
+ else
+ std::copy_n(out + 1, integral_size, out);
+ out[integral_size] = decimal_point;
+ return end;
+}
+
+template <typename OutputIt, typename UInt, typename Char,
+ FMT_ENABLE_IF(!std::is_pointer<remove_cvref_t<OutputIt>>::value)>
+inline OutputIt write_significand(OutputIt out, UInt significand,
+ int significand_size, int integral_size,
+ Char decimal_point) {
+ // Buffer is large enough to hold digits (digits10 + 1) and a decimal point.
+ Char buffer[digits10<UInt>() + 2];
+ auto end = write_significand(buffer, significand, significand_size,
+ integral_size, decimal_point);
+ return detail::copy_str<Char>(buffer, end, out);
+}
+
+template <typename OutputIt, typename Char>
+inline OutputIt write_significand(OutputIt out, const char* significand,
+ int significand_size, int integral_size,
+ Char decimal_point) {
+ out = detail::copy_str<Char>(significand, significand + integral_size, out);
+ if (!decimal_point) return out;
+ *out++ = decimal_point;
+ return detail::copy_str<Char>(significand + integral_size,
+ significand + significand_size, out);
+}
+
+template <typename OutputIt, typename DecimalFP, typename Char>
+OutputIt write_float(OutputIt out, const DecimalFP& fp,
+ const basic_format_specs<Char>& specs, float_specs fspecs,
+ Char decimal_point) {
+ auto significand = fp.significand;
+ int significand_size = get_significand_size(fp);
+ static const Char zero = static_cast<Char>('0');
+ auto sign = fspecs.sign;
+ size_t size = to_unsigned(significand_size) + (sign ? 1 : 0);
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+
+ int output_exp = fp.exponent + significand_size - 1;
+ auto use_exp_format = [=]() {
+ if (fspecs.format == float_format::exp) return true;
+ if (fspecs.format != float_format::general) return false;
+ // Use the fixed notation if the exponent is in [exp_lower, exp_upper),
+ // e.g. 0.0001 instead of 1e-04. Otherwise use the exponent notation.
+ const int exp_lower = -4, exp_upper = 16;
+ return output_exp < exp_lower ||
+ output_exp >= (fspecs.precision > 0 ? fspecs.precision : exp_upper);
+ };
+ if (use_exp_format()) {
+ int num_zeros = 0;
+ if (fspecs.showpoint) {
+ num_zeros = (std::max)(fspecs.precision - significand_size, 0);
+ size += to_unsigned(num_zeros);
+ } else if (significand_size == 1) {
+ decimal_point = Char();
+ }
+ auto abs_output_exp = output_exp >= 0 ? output_exp : -output_exp;
+ int exp_digits = 2;
+ if (abs_output_exp >= 100) exp_digits = abs_output_exp >= 1000 ? 4 : 3;
+
+ size += to_unsigned((decimal_point ? 1 : 0) + 2 + exp_digits);
+ char exp_char = fspecs.upper ? 'E' : 'e';
+ auto write = [=](iterator it) {
+ if (sign) *it++ = static_cast<Char>(data::signs[sign]);
+ // Insert a decimal point after the first digit and add an exponent.
+ it = write_significand(it, significand, significand_size, 1,
+ decimal_point);
+ if (num_zeros > 0) it = std::fill_n(it, num_zeros, zero);
+ *it++ = static_cast<Char>(exp_char);
+ return write_exponent<Char>(output_exp, it);
+ };
+ return specs.width > 0 ? write_padded<align::right>(out, specs, size, write)
+ : base_iterator(out, write(reserve(out, size)));
+ }
+
+ int exp = fp.exponent + significand_size;
+ if (fp.exponent >= 0) {
+ // 1234e5 -> 123400000[.0+]
+ size += to_unsigned(fp.exponent);
+ int num_zeros = fspecs.precision - exp;
+#ifdef FMT_FUZZ
+ if (num_zeros > 5000)
+ throw std::runtime_error("fuzz mode - avoiding excessive cpu use");
+#endif
+ if (fspecs.showpoint) {
+ if (num_zeros <= 0 && fspecs.format != float_format::fixed) num_zeros = 1;
+ if (num_zeros > 0) size += to_unsigned(num_zeros);
+ }
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = static_cast<Char>(data::signs[sign]);
+ it = write_significand<Char>(it, significand, significand_size);
+ it = std::fill_n(it, fp.exponent, zero);
+ if (!fspecs.showpoint) return it;
+ *it++ = decimal_point;
+ return num_zeros > 0 ? std::fill_n(it, num_zeros, zero) : it;
+ });
+ } else if (exp > 0) {
+ // 1234e-2 -> 12.34[0+]
+ int num_zeros = fspecs.showpoint ? fspecs.precision - significand_size : 0;
+ size += 1 + to_unsigned(num_zeros > 0 ? num_zeros : 0);
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = static_cast<Char>(data::signs[sign]);
+ it = write_significand(it, significand, significand_size, exp,
+ decimal_point);
+ return num_zeros > 0 ? std::fill_n(it, num_zeros, zero) : it;
+ });
+ }
+ // 1234e-6 -> 0.001234
+ int num_zeros = -exp;
+ if (significand_size == 0 && fspecs.precision >= 0 &&
+ fspecs.precision < num_zeros) {
+ num_zeros = fspecs.precision;
+ }
+ size += 2 + to_unsigned(num_zeros);
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = static_cast<Char>(data::signs[sign]);
+ *it++ = zero;
+ if (num_zeros == 0 && significand_size == 0 && !fspecs.showpoint) return it;
+ *it++ = decimal_point;
+ it = std::fill_n(it, num_zeros, zero);
+ return write_significand<Char>(it, significand, significand_size);
+ });
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+OutputIt write(OutputIt out, T value, basic_format_specs<Char> specs,
+ locale_ref loc = {}) {
+ if (const_check(!is_supported_floating_point(value))) return out;
+ float_specs fspecs = parse_float_type_spec(specs);
+ fspecs.sign = specs.sign;
+ if (std::signbit(value)) { // value < 0 is false for NaN so use signbit.
+ fspecs.sign = sign::minus;
+ value = -value;
+ } else if (fspecs.sign == sign::minus) {
+ fspecs.sign = sign::none;
+ }
+
+ if (!std::isfinite(value))
+ return write_nonfinite(out, std::isinf(value), specs, fspecs);
+
+ if (specs.align == align::numeric && fspecs.sign) {
+ auto it = reserve(out, 1);
+ *it++ = static_cast<Char>(data::signs[fspecs.sign]);
+ out = base_iterator(out, it);
+ fspecs.sign = sign::none;
+ if (specs.width != 0) --specs.width;
+ }
+
+ memory_buffer buffer;
+ if (fspecs.format == float_format::hex) {
+ if (fspecs.sign) buffer.push_back(data::signs[fspecs.sign]);
+ snprintf_float(promote_float(value), specs.precision, fspecs, buffer);
+ return write_bytes(out, {buffer.data(), buffer.size()}, specs);
+ }
+ int precision = specs.precision >= 0 || !specs.type ? specs.precision : 6;
+ if (fspecs.format == float_format::exp) {
+ if (precision == max_value<int>())
+ FMT_THROW(format_error("number is too big"));
+ else
+ ++precision;
+ }
+ if (const_check(std::is_same<T, float>())) fspecs.binary32 = true;
+ fspecs.use_grisu = is_fast_float<T>();
+ int exp = format_float(promote_float(value), precision, fspecs, buffer);
+ fspecs.precision = precision;
+ Char point =
+ fspecs.locale ? decimal_point<Char>(loc) : static_cast<Char>('.');
+ auto fp = big_decimal_fp{buffer.data(), static_cast<int>(buffer.size()), exp};
+ return write_float(out, fp, specs, fspecs, point);
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_fast_float<T>::value)>
+OutputIt write(OutputIt out, T value) {
+ if (const_check(!is_supported_floating_point(value))) return out;
+
+ using floaty = conditional_t<std::is_same<T, long double>::value, double, T>;
+ using uint = typename dragonbox::float_info<floaty>::carrier_uint;
+ auto bits = bit_cast<uint>(value);
+
+ auto fspecs = float_specs();
+ auto sign_bit = bits & (uint(1) << (num_bits<uint>() - 1));
+ if (sign_bit != 0) {
+ fspecs.sign = sign::minus;
+ value = -value;
+ }
+
+ static const auto specs = basic_format_specs<Char>();
+ uint mask = exponent_mask<floaty>();
+ if ((bits & mask) == mask)
+ return write_nonfinite(out, std::isinf(value), specs, fspecs);
+
+ auto dec = dragonbox::to_decimal(static_cast<floaty>(value));
+ return write_float(out, dec, specs, fspecs, static_cast<Char>('.'));
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(std::is_floating_point<T>::value &&
+ !is_fast_float<T>::value)>
+inline OutputIt write(OutputIt out, T value) {
+ return write(out, value, basic_format_specs<Char>());
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write_char(OutputIt out, Char value,
+ const basic_format_specs<Char>& specs) {
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ return write_padded(out, specs, 1, [=](iterator it) {
+ *it++ = value;
+ return it;
+ });
+}
+
+template <typename Char, typename OutputIt, typename UIntPtr>
+OutputIt write_ptr(OutputIt out, UIntPtr value,
+ const basic_format_specs<Char>* specs) {
+ int num_digits = count_digits<4>(value);
+ auto size = to_unsigned(num_digits) + size_t(2);
+ using iterator = remove_reference_t<decltype(reserve(out, 0))>;
+ auto write = [=](iterator it) {
+ *it++ = static_cast<Char>('0');
+ *it++ = static_cast<Char>('x');
+ return format_uint<4, Char>(it, value, num_digits);
+ };
+ return specs ? write_padded<align::right>(out, *specs, size, write)
+ : base_iterator(out, write(reserve(out, size)));
+}
+
+template <typename T> struct is_integral : std::is_integral<T> {};
+template <> struct is_integral<int128_t> : std::true_type {};
+template <> struct is_integral<uint128_t> : std::true_type {};
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, monostate) {
+ FMT_ASSERT(false, "");
+ return out;
+}
+
+template <typename Char, typename OutputIt,
+ FMT_ENABLE_IF(!std::is_same<Char, char>::value)>
+OutputIt write(OutputIt out, string_view value) {
+ auto it = reserve(out, value.size());
+ it = copy_str<Char>(value.begin(), value.end(), it);
+ return base_iterator(out, it);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, basic_string_view<Char> value) {
+ auto it = reserve(out, value.size());
+ it = std::copy(value.begin(), value.end(), it);
+ return base_iterator(out, it);
+}
+
+template <typename Char>
+buffer_appender<Char> write(buffer_appender<Char> out,
+ basic_string_view<Char> value) {
+ get_container(out).append(value.begin(), value.end());
+ return out;
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_integral<T>::value &&
+ !std::is_same<T, bool>::value &&
+ !std::is_same<T, Char>::value)>
+OutputIt write(OutputIt out, T value) {
+ auto abs_value = static_cast<uint32_or_64_or_128_t<T>>(value);
+ bool negative = is_negative(value);
+ // Don't do -abs_value since it trips unsigned-integer-overflow sanitizer.
+ if (negative) abs_value = ~abs_value + 1;
+ int num_digits = count_digits(abs_value);
+ auto size = (negative ? 1 : 0) + static_cast<size_t>(num_digits);
+ auto it = reserve(out, size);
+ if (auto ptr = to_pointer<Char>(it, size)) {
+ if (negative) *ptr++ = static_cast<Char>('-');
+ format_decimal<Char>(ptr, abs_value, num_digits);
+ return out;
+ }
+ if (negative) *it++ = static_cast<Char>('-');
+ it = format_decimal<Char>(it, abs_value, num_digits).end;
+ return base_iterator(out, it);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, bool value) {
+ return write<Char>(out, string_view(value ? "true" : "false"));
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, Char value) {
+ auto it = reserve(out, 1);
+ *it++ = value;
+ return base_iterator(out, it);
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, const Char* value) {
+ if (!value) {
+ FMT_THROW(format_error("string pointer is null"));
+ } else {
+ auto length = std::char_traits<Char>::length(value);
+ out = write(out, basic_string_view<Char>(value, length));
+ }
+ return out;
+}
+
+template <typename Char, typename OutputIt>
+OutputIt write(OutputIt out, const void* value) {
+ return write_ptr<Char>(out, to_uintptr(value), nullptr);
+}
+
+template <typename Char, typename OutputIt, typename T>
+auto write(OutputIt out, const T& value) -> typename std::enable_if<
+ mapped_type_constant<T, basic_format_context<OutputIt, Char>>::value ==
+ type::custom_type,
+ OutputIt>::type {
+ using context_type = basic_format_context<OutputIt, Char>;
+ using formatter_type =
+ conditional_t<has_formatter<T, context_type>::value,
+ typename context_type::template formatter_type<T>,
+ fallback_formatter<T, Char>>;
+ context_type ctx(out, {}, {});
+ return formatter_type().format(value, ctx);
+}
+
+// An argument visitor that formats the argument and writes it via the output
+// iterator. It's a class and not a generic lambda for compatibility with C++11.
+template <typename OutputIt, typename Char> struct default_arg_formatter {
+ using context = basic_format_context<OutputIt, Char>;
+
+ OutputIt out;
+ basic_format_args<context> args;
+ locale_ref loc;
+
+ template <typename T> OutputIt operator()(T value) {
+ return write<Char>(out, value);
+ }
+
+ OutputIt operator()(typename basic_format_arg<context>::handle handle) {
+ basic_format_parse_context<Char> parse_ctx({});
+ basic_format_context<OutputIt, Char> format_ctx(out, args, loc);
+ handle.format(parse_ctx, format_ctx);
+ return format_ctx.out();
+ }
+};
+
+template <typename OutputIt, typename Char,
+ typename ErrorHandler = error_handler>
+class arg_formatter_base {
+ public:
+ using iterator = OutputIt;
+ using char_type = Char;
+ using format_specs = basic_format_specs<Char>;
+
+ private:
+ iterator out_;
+ locale_ref locale_;
+ format_specs* specs_;
+
+ // Attempts to reserve space for n extra characters in the output range.
+ // Returns a pointer to the reserved range or a reference to out_.
+ auto reserve(size_t n) -> decltype(detail::reserve(out_, n)) {
+ return detail::reserve(out_, n);
+ }
+
+ using reserve_iterator = remove_reference_t<decltype(
+ detail::reserve(std::declval<iterator&>(), 0))>;
+
+ template <typename T> void write_int(T value, const format_specs& spec) {
+ using uint_type = uint32_or_64_or_128_t<T>;
+ int_writer<iterator, Char, uint_type> w(out_, locale_, value, spec);
+ handle_int_type_spec(spec.type, w);
+ out_ = w.out;
+ }
+
+ void write(char value) {
+ auto&& it = reserve(1);
+ *it++ = value;
+ }
+
+ template <typename Ch, FMT_ENABLE_IF(std::is_same<Ch, Char>::value)>
+ void write(Ch value) {
+ out_ = detail::write<Char>(out_, value);
+ }
+
+ void write(string_view value) {
+ auto&& it = reserve(value.size());
+ it = copy_str<Char>(value.begin(), value.end(), it);
+ }
+ void write(wstring_view value) {
+ static_assert(std::is_same<Char, wchar_t>::value, "");
+ auto&& it = reserve(value.size());
+ it = std::copy(value.begin(), value.end(), it);
+ }
+
+ template <typename Ch>
+ void write(const Ch* s, size_t size, const format_specs& specs) {
+ auto width = specs.width != 0
+ ? count_code_points(basic_string_view<Ch>(s, size))
+ : 0;
+ out_ = write_padded(out_, specs, size, width, [=](reserve_iterator it) {
+ return copy_str<Char>(s, s + size, it);
+ });
+ }
+
+ template <typename Ch>
+ void write(basic_string_view<Ch> s, const format_specs& specs = {}) {
+ out_ = detail::write(out_, s, specs);
+ }
+
+ void write_pointer(const void* p) {
+ out_ = write_ptr<char_type>(out_, to_uintptr(p), specs_);
+ }
+
+ struct char_spec_handler : ErrorHandler {
+ arg_formatter_base& formatter;
+ Char value;
+
+ char_spec_handler(arg_formatter_base& f, Char val)
+ : formatter(f), value(val) {}
+
+ void on_int() {
+ // char is only formatted as int if there are specs.
+ formatter.write_int(static_cast<int>(value), *formatter.specs_);
+ }
+ void on_char() {
+ if (formatter.specs_)
+ formatter.out_ = write_char(formatter.out_, value, *formatter.specs_);
+ else
+ formatter.write(value);
+ }
+ };
+
+ struct cstring_spec_handler : error_handler {
+ arg_formatter_base& formatter;
+ const Char* value;
+
+ cstring_spec_handler(arg_formatter_base& f, const Char* val)
+ : formatter(f), value(val) {}
+
+ void on_string() { formatter.write(value); }
+ void on_pointer() { formatter.write_pointer(value); }
+ };
+
+ protected:
+ iterator out() { return out_; }
+ format_specs* specs() { return specs_; }
+
+ void write(bool value) {
+ if (specs_)
+ write(string_view(value ? "true" : "false"), *specs_);
+ else
+ out_ = detail::write<Char>(out_, value);
+ }
+
+ void write(const Char* value) {
+ if (!value) {
+ FMT_THROW(format_error("string pointer is null"));
+ } else {
+ auto length = std::char_traits<char_type>::length(value);
+ basic_string_view<char_type> sv(value, length);
+ specs_ ? write(sv, *specs_) : write(sv);
+ }
+ }
+
+ public:
+ arg_formatter_base(OutputIt out, format_specs* s, locale_ref loc)
+ : out_(out), locale_(loc), specs_(s) {}
+
+ iterator operator()(monostate) {
+ FMT_ASSERT(false, "invalid argument type");
+ return out_;
+ }
+
+ template <typename T, FMT_ENABLE_IF(is_integral<T>::value)>
+ FMT_INLINE iterator operator()(T value) {
+ if (specs_)
+ write_int(value, *specs_);
+ else
+ out_ = detail::write<Char>(out_, value);
+ return out_;
+ }
+
+ iterator operator()(Char value) {
+ handle_char_specs(specs_,
+ char_spec_handler(*this, static_cast<Char>(value)));
+ return out_;
+ }
+
+ iterator operator()(bool value) {
+ if (specs_ && specs_->type) return (*this)(value ? 1 : 0);
+ write(value != 0);
+ return out_;
+ }
+
+ template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value)>
+ iterator operator()(T value) {
+ auto specs = specs_ ? *specs_ : format_specs();
+ if (const_check(is_supported_floating_point(value)))
+ out_ = detail::write(out_, value, specs, locale_);
+ else
+ FMT_ASSERT(false, "unsupported float argument type");
+ return out_;
+ }
+
+ iterator operator()(const Char* value) {
+ if (!specs_) return write(value), out_;
+ handle_cstring_type_spec(specs_->type, cstring_spec_handler(*this, value));
+ return out_;
+ }
+
+ iterator operator()(basic_string_view<Char> value) {
+ if (specs_) {
+ check_string_type_spec(specs_->type, error_handler());
+ write(value, *specs_);
+ } else {
+ write(value);
+ }
+ return out_;
+ }
+
+ iterator operator()(const void* value) {
+ if (specs_) check_pointer_type_spec(specs_->type, error_handler());
+ write_pointer(value);
+ return out_;
+ }
+};
+
+/** The default argument formatter. */
+template <typename OutputIt, typename Char>
+class arg_formatter : public arg_formatter_base<OutputIt, Char> {
+ private:
+ using char_type = Char;
+ using base = arg_formatter_base<OutputIt, Char>;
+ using context_type = basic_format_context<OutputIt, Char>;
+
+ context_type& ctx_;
+ basic_format_parse_context<char_type>* parse_ctx_;
+ const Char* ptr_;
+
+ public:
+ using iterator = typename base::iterator;
+ using format_specs = typename base::format_specs;
+
+ /**
+ \rst
+ Constructs an argument formatter object.
+ *ctx* is a reference to the formatting context,
+ *specs* contains format specifier information for standard argument types.
+ \endrst
+ */
+ explicit arg_formatter(
+ context_type& ctx,
+ basic_format_parse_context<char_type>* parse_ctx = nullptr,
+ format_specs* specs = nullptr, const Char* ptr = nullptr)
+ : base(ctx.out(), specs, ctx.locale()),
+ ctx_(ctx),
+ parse_ctx_(parse_ctx),
+ ptr_(ptr) {}
+
+ using base::operator();
+
+ /** Formats an argument of a user-defined type. */
+ iterator operator()(typename basic_format_arg<context_type>::handle handle) {
+ if (ptr_) advance_to(*parse_ctx_, ptr_);
+ handle.format(*parse_ctx_, ctx_);
+ return ctx_.out();
+ }
+};
+
+template <typename Char> FMT_CONSTEXPR bool is_name_start(Char c) {
+ return ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') || '_' == c;
+}
+
+// Parses the range [begin, end) as an unsigned integer. This function assumes
+// that the range is non-empty and the first character is a digit.
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR int parse_nonnegative_int(const Char*& begin, const Char* end,
+ ErrorHandler&& eh) {
+ FMT_ASSERT(begin != end && '0' <= *begin && *begin <= '9', "");
+ unsigned value = 0;
+ // Convert to unsigned to prevent a warning.
+ constexpr unsigned max_int = max_value<int>();
+ unsigned big = max_int / 10;
+ do {
+ // Check for overflow.
+ if (value > big) {
+ value = max_int + 1;
+ break;
+ }
+ value = value * 10 + unsigned(*begin - '0');
+ ++begin;
+ } while (begin != end && '0' <= *begin && *begin <= '9');
+ if (value > max_int) eh.on_error("number is too big");
+ return static_cast<int>(value);
+}
+
+template <typename Context> class custom_formatter {
+ private:
+ using char_type = typename Context::char_type;
+
+ basic_format_parse_context<char_type>& parse_ctx_;
+ Context& ctx_;
+
+ public:
+ explicit custom_formatter(basic_format_parse_context<char_type>& parse_ctx,
+ Context& ctx)
+ : parse_ctx_(parse_ctx), ctx_(ctx) {}
+
+ void operator()(typename basic_format_arg<Context>::handle h) const {
+ h.format(parse_ctx_, ctx_);
+ }
+
+ template <typename T> void operator()(T) const {}
+};
+
+template <typename T>
+using is_integer =
+ bool_constant<is_integral<T>::value && !std::is_same<T, bool>::value &&
+ !std::is_same<T, char>::value &&
+ !std::is_same<T, wchar_t>::value>;
+
+template <typename ErrorHandler> class width_checker {
+ public:
+ explicit FMT_CONSTEXPR width_checker(ErrorHandler& eh) : handler_(eh) {}
+
+ template <typename T, FMT_ENABLE_IF(is_integer<T>::value)>
+ FMT_CONSTEXPR unsigned long long operator()(T value) {
+ if (is_negative(value)) handler_.on_error("negative width");
+ return static_cast<unsigned long long>(value);
+ }
+
+ template <typename T, FMT_ENABLE_IF(!is_integer<T>::value)>
+ FMT_CONSTEXPR unsigned long long operator()(T) {
+ handler_.on_error("width is not integer");
+ return 0;
+ }
+
+ private:
+ ErrorHandler& handler_;
+};
+
+template <typename ErrorHandler> class precision_checker {
+ public:
+ explicit FMT_CONSTEXPR precision_checker(ErrorHandler& eh) : handler_(eh) {}
+
+ template <typename T, FMT_ENABLE_IF(is_integer<T>::value)>
+ FMT_CONSTEXPR unsigned long long operator()(T value) {
+ if (is_negative(value)) handler_.on_error("negative precision");
+ return static_cast<unsigned long long>(value);
+ }
+
+ template <typename T, FMT_ENABLE_IF(!is_integer<T>::value)>
+ FMT_CONSTEXPR unsigned long long operator()(T) {
+ handler_.on_error("precision is not integer");
+ return 0;
+ }
+
+ private:
+ ErrorHandler& handler_;
+};
+
+// A format specifier handler that sets fields in basic_format_specs.
+template <typename Char> class specs_setter {
+ public:
+ explicit FMT_CONSTEXPR specs_setter(basic_format_specs<Char>& specs)
+ : specs_(specs) {}
+
+ FMT_CONSTEXPR specs_setter(const specs_setter& other)
+ : specs_(other.specs_) {}
+
+ FMT_CONSTEXPR void on_align(align_t align) { specs_.align = align; }
+ FMT_CONSTEXPR void on_fill(basic_string_view<Char> fill) {
+ specs_.fill = fill;
+ }
+ FMT_CONSTEXPR void on_plus() { specs_.sign = sign::plus; }
+ FMT_CONSTEXPR void on_minus() { specs_.sign = sign::minus; }
+ FMT_CONSTEXPR void on_space() { specs_.sign = sign::space; }
+ FMT_CONSTEXPR void on_hash() { specs_.alt = true; }
+
+ FMT_CONSTEXPR void on_zero() {
+ specs_.align = align::numeric;
+ specs_.fill[0] = Char('0');
+ }
+
+ FMT_CONSTEXPR void on_width(int width) { specs_.width = width; }
+ FMT_CONSTEXPR void on_precision(int precision) {
+ specs_.precision = precision;
+ }
+ FMT_CONSTEXPR void end_precision() {}
+
+ FMT_CONSTEXPR void on_type(Char type) {
+ specs_.type = static_cast<char>(type);
+ }
+
+ protected:
+ basic_format_specs<Char>& specs_;
+};
+
+template <typename ErrorHandler> class numeric_specs_checker {
+ public:
+ FMT_CONSTEXPR numeric_specs_checker(ErrorHandler& eh, detail::type arg_type)
+ : error_handler_(eh), arg_type_(arg_type) {}
+
+ FMT_CONSTEXPR void require_numeric_argument() {
+ if (!is_arithmetic_type(arg_type_))
+ error_handler_.on_error("format specifier requires numeric argument");
+ }
+
+ FMT_CONSTEXPR void check_sign() {
+ require_numeric_argument();
+ if (is_integral_type(arg_type_) && arg_type_ != type::int_type &&
+ arg_type_ != type::long_long_type && arg_type_ != type::char_type) {
+ error_handler_.on_error("format specifier requires signed argument");
+ }
+ }
+
+ FMT_CONSTEXPR void check_precision() {
+ if (is_integral_type(arg_type_) || arg_type_ == type::pointer_type)
+ error_handler_.on_error("precision not allowed for this argument type");
+ }
+
+ private:
+ ErrorHandler& error_handler_;
+ detail::type arg_type_;
+};
+
+// A format specifier handler that checks if specifiers are consistent with the
+// argument type.
+template <typename Handler> class specs_checker : public Handler {
+ private:
+ numeric_specs_checker<Handler> checker_;
+
+ // Suppress an MSVC warning about using this in initializer list.
+ FMT_CONSTEXPR Handler& error_handler() { return *this; }
+
+ public:
+ FMT_CONSTEXPR specs_checker(const Handler& handler, detail::type arg_type)
+ : Handler(handler), checker_(error_handler(), arg_type) {}
+
+ FMT_CONSTEXPR specs_checker(const specs_checker& other)
+ : Handler(other), checker_(error_handler(), other.arg_type_) {}
+
+ FMT_CONSTEXPR void on_align(align_t align) {
+ if (align == align::numeric) checker_.require_numeric_argument();
+ Handler::on_align(align);
+ }
+
+ FMT_CONSTEXPR void on_plus() {
+ checker_.check_sign();
+ Handler::on_plus();
+ }
+
+ FMT_CONSTEXPR void on_minus() {
+ checker_.check_sign();
+ Handler::on_minus();
+ }
+
+ FMT_CONSTEXPR void on_space() {
+ checker_.check_sign();
+ Handler::on_space();
+ }
+
+ FMT_CONSTEXPR void on_hash() {
+ checker_.require_numeric_argument();
+ Handler::on_hash();
+ }
+
+ FMT_CONSTEXPR void on_zero() {
+ checker_.require_numeric_argument();
+ Handler::on_zero();
+ }
+
+ FMT_CONSTEXPR void end_precision() { checker_.check_precision(); }
+};
+
+template <template <typename> class Handler, typename FormatArg,
+ typename ErrorHandler>
+FMT_CONSTEXPR int get_dynamic_spec(FormatArg arg, ErrorHandler eh) {
+ unsigned long long value = visit_format_arg(Handler<ErrorHandler>(eh), arg);
+ if (value > to_unsigned(max_value<int>())) eh.on_error("number is too big");
+ return static_cast<int>(value);
+}
+
+struct auto_id {};
+
+template <typename Context, typename ID>
+FMT_CONSTEXPR typename Context::format_arg get_arg(Context& ctx, ID id) {
+ auto arg = ctx.arg(id);
+ if (!arg) ctx.on_error("argument not found");
+ return arg;
+}
+
+// The standard format specifier handler with checking.
+template <typename ParseContext, typename Context>
+class specs_handler : public specs_setter<typename Context::char_type> {
+ public:
+ using char_type = typename Context::char_type;
+
+ FMT_CONSTEXPR specs_handler(basic_format_specs<char_type>& specs,
+ ParseContext& parse_ctx, Context& ctx)
+ : specs_setter<char_type>(specs),
+ parse_context_(parse_ctx),
+ context_(ctx) {}
+
+ template <typename Id> FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
+ this->specs_.width = get_dynamic_spec<width_checker>(
+ get_arg(arg_id), context_.error_handler());
+ }
+
+ template <typename Id> FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
+ this->specs_.precision = get_dynamic_spec<precision_checker>(
+ get_arg(arg_id), context_.error_handler());
+ }
+
+ void on_error(const char* message) { context_.on_error(message); }
+
+ private:
+ // This is only needed for compatibility with gcc 4.4.
+ using format_arg = typename Context::format_arg;
+
+ FMT_CONSTEXPR format_arg get_arg(auto_id) {
+ return detail::get_arg(context_, parse_context_.next_arg_id());
+ }
+
+ FMT_CONSTEXPR format_arg get_arg(int arg_id) {
+ parse_context_.check_arg_id(arg_id);
+ return detail::get_arg(context_, arg_id);
+ }
+
+ FMT_CONSTEXPR format_arg get_arg(basic_string_view<char_type> arg_id) {
+ parse_context_.check_arg_id(arg_id);
+ return detail::get_arg(context_, arg_id);
+ }
+
+ ParseContext& parse_context_;
+ Context& context_;
+};
+
+enum class arg_id_kind { none, index, name };
+
+// An argument reference.
+template <typename Char> struct arg_ref {
+ FMT_CONSTEXPR arg_ref() : kind(arg_id_kind::none), val() {}
+
+ FMT_CONSTEXPR explicit arg_ref(int index)
+ : kind(arg_id_kind::index), val(index) {}
+ FMT_CONSTEXPR explicit arg_ref(basic_string_view<Char> name)
+ : kind(arg_id_kind::name), val(name) {}
+
+ FMT_CONSTEXPR arg_ref& operator=(int idx) {
+ kind = arg_id_kind::index;
+ val.index = idx;
+ return *this;
+ }
+
+ arg_id_kind kind;
+ union value {
+ FMT_CONSTEXPR value(int id = 0) : index{id} {}
+ FMT_CONSTEXPR value(basic_string_view<Char> n) : name(n) {}
+
+ int index;
+ basic_string_view<Char> name;
+ } val;
+};
+
+// Format specifiers with width and precision resolved at formatting rather
+// than parsing time to allow re-using the same parsed specifiers with
+// different sets of arguments (precompilation of format strings).
+template <typename Char>
+struct dynamic_format_specs : basic_format_specs<Char> {
+ arg_ref<Char> width_ref;
+ arg_ref<Char> precision_ref;
+};
+
+// Format spec handler that saves references to arguments representing dynamic
+// width and precision to be resolved at formatting time.
+template <typename ParseContext>
+class dynamic_specs_handler
+ : public specs_setter<typename ParseContext::char_type> {
+ public:
+ using char_type = typename ParseContext::char_type;
+
+ FMT_CONSTEXPR dynamic_specs_handler(dynamic_format_specs<char_type>& specs,
+ ParseContext& ctx)
+ : specs_setter<char_type>(specs), specs_(specs), context_(ctx) {}
+
+ FMT_CONSTEXPR dynamic_specs_handler(const dynamic_specs_handler& other)
+ : specs_setter<char_type>(other),
+ specs_(other.specs_),
+ context_(other.context_) {}
+
+ template <typename Id> FMT_CONSTEXPR void on_dynamic_width(Id arg_id) {
+ specs_.width_ref = make_arg_ref(arg_id);
+ }
+
+ template <typename Id> FMT_CONSTEXPR void on_dynamic_precision(Id arg_id) {
+ specs_.precision_ref = make_arg_ref(arg_id);
+ }
+
+ FMT_CONSTEXPR void on_error(const char* message) {
+ context_.on_error(message);
+ }
+
+ private:
+ using arg_ref_type = arg_ref<char_type>;
+
+ FMT_CONSTEXPR arg_ref_type make_arg_ref(int arg_id) {
+ context_.check_arg_id(arg_id);
+ return arg_ref_type(arg_id);
+ }
+
+ FMT_CONSTEXPR arg_ref_type make_arg_ref(auto_id) {
+ return arg_ref_type(context_.next_arg_id());
+ }
+
+ FMT_CONSTEXPR arg_ref_type make_arg_ref(basic_string_view<char_type> arg_id) {
+ context_.check_arg_id(arg_id);
+ basic_string_view<char_type> format_str(
+ context_.begin(), to_unsigned(context_.end() - context_.begin()));
+ return arg_ref_type(arg_id);
+ }
+
+ dynamic_format_specs<char_type>& specs_;
+ ParseContext& context_;
+};
+
+template <typename Char, typename IDHandler>
+FMT_CONSTEXPR const Char* parse_arg_id(const Char* begin, const Char* end,
+ IDHandler&& handler) {
+ FMT_ASSERT(begin != end, "");
+ Char c = *begin;
+ if (c == '}' || c == ':') {
+ handler();
+ return begin;
+ }
+ if (c >= '0' && c <= '9') {
+ int index = 0;
+ if (c != '0')
+ index = parse_nonnegative_int(begin, end, handler);
+ else
+ ++begin;
+ if (begin == end || (*begin != '}' && *begin != ':'))
+ handler.on_error("invalid format string");
+ else
+ handler(index);
+ return begin;
+ }
+ if (!is_name_start(c)) {
+ handler.on_error("invalid format string");
+ return begin;
+ }
+ auto it = begin;
+ do {
+ ++it;
+ } while (it != end && (is_name_start(c = *it) || ('0' <= c && c <= '9')));
+ handler(basic_string_view<Char>(begin, to_unsigned(it - begin)));
+ return it;
+}
+
+// Adapts SpecHandler to IDHandler API for dynamic width.
+template <typename SpecHandler, typename Char> struct width_adapter {
+ explicit FMT_CONSTEXPR width_adapter(SpecHandler& h) : handler(h) {}
+
+ FMT_CONSTEXPR void operator()() { handler.on_dynamic_width(auto_id()); }
+ FMT_CONSTEXPR void operator()(int id) { handler.on_dynamic_width(id); }
+ FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+ handler.on_dynamic_width(id);
+ }
+
+ FMT_CONSTEXPR void on_error(const char* message) {
+ handler.on_error(message);
+ }
+
+ SpecHandler& handler;
+};
+
+// Adapts SpecHandler to IDHandler API for dynamic precision.
+template <typename SpecHandler, typename Char> struct precision_adapter {
+ explicit FMT_CONSTEXPR precision_adapter(SpecHandler& h) : handler(h) {}
+
+ FMT_CONSTEXPR void operator()() { handler.on_dynamic_precision(auto_id()); }
+ FMT_CONSTEXPR void operator()(int id) { handler.on_dynamic_precision(id); }
+ FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+ handler.on_dynamic_precision(id);
+ }
+
+ FMT_CONSTEXPR void on_error(const char* message) {
+ handler.on_error(message);
+ }
+
+ SpecHandler& handler;
+};
+
+template <typename Char>
+FMT_CONSTEXPR int code_point_length(const Char* begin) {
+ if (const_check(sizeof(Char) != 1)) return 1;
+ constexpr char lengths[] = {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 3, 3, 4, 0};
+ int len = lengths[static_cast<unsigned char>(*begin) >> 3];
+
+ // Compute the pointer to the next character early so that the next
+ // iteration can start working on the next character. Neither Clang
+ // nor GCC figure out this reordering on their own.
+ return len + !len;
+}
+
+template <typename Char> constexpr bool is_ascii_letter(Char c) {
+ return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z');
+}
+
+// Converts a character to ASCII. Returns a number > 127 on conversion failure.
+template <typename Char, FMT_ENABLE_IF(std::is_integral<Char>::value)>
+constexpr Char to_ascii(Char value) {
+ return value;
+}
+template <typename Char, FMT_ENABLE_IF(std::is_enum<Char>::value)>
+constexpr typename std::underlying_type<Char>::type to_ascii(Char value) {
+ return value;
+}
+
+// Parses fill and alignment.
+template <typename Char, typename Handler>
+FMT_CONSTEXPR const Char* parse_align(const Char* begin, const Char* end,
+ Handler&& handler) {
+ FMT_ASSERT(begin != end, "");
+ auto align = align::none;
+ auto p = begin + code_point_length(begin);
+ if (p >= end) p = begin;
+ for (;;) {
+ switch (to_ascii(*p)) {
+ case '<':
+ align = align::left;
+ break;
+ case '>':
+ align = align::right;
+ break;
+#if FMT_DEPRECATED_NUMERIC_ALIGN
+ case '=':
+ align = align::numeric;
+ break;
+#endif
+ case '^':
+ align = align::center;
+ break;
+ }
+ if (align != align::none) {
+ if (p != begin) {
+ auto c = *begin;
+ if (c == '{')
+ return handler.on_error("invalid fill character '{'"), begin;
+ handler.on_fill(basic_string_view<Char>(begin, to_unsigned(p - begin)));
+ begin = p + 1;
+ } else
+ ++begin;
+ handler.on_align(align);
+ break;
+ } else if (p == begin) {
+ break;
+ }
+ p = begin;
+ }
+ return begin;
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR const Char* parse_width(const Char* begin, const Char* end,
+ Handler&& handler) {
+ FMT_ASSERT(begin != end, "");
+ if ('0' <= *begin && *begin <= '9') {
+ handler.on_width(parse_nonnegative_int(begin, end, handler));
+ } else if (*begin == '{') {
+ ++begin;
+ if (begin != end)
+ begin = parse_arg_id(begin, end, width_adapter<Handler, Char>(handler));
+ if (begin == end || *begin != '}')
+ return handler.on_error("invalid format string"), begin;
+ ++begin;
+ }
+ return begin;
+}
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR const Char* parse_precision(const Char* begin, const Char* end,
+ Handler&& handler) {
+ ++begin;
+ auto c = begin != end ? *begin : Char();
+ if ('0' <= c && c <= '9') {
+ handler.on_precision(parse_nonnegative_int(begin, end, handler));
+ } else if (c == '{') {
+ ++begin;
+ if (begin != end) {
+ begin =
+ parse_arg_id(begin, end, precision_adapter<Handler, Char>(handler));
+ }
+ if (begin == end || *begin++ != '}')
+ return handler.on_error("invalid format string"), begin;
+ } else {
+ return handler.on_error("missing precision specifier"), begin;
+ }
+ handler.end_precision();
+ return begin;
+}
+
+// Parses standard format specifiers and sends notifications about parsed
+// components to handler.
+template <typename Char, typename SpecHandler>
+FMT_CONSTEXPR const Char* parse_format_specs(const Char* begin, const Char* end,
+ SpecHandler&& handler) {
+ if (begin == end) return begin;
+
+ begin = parse_align(begin, end, handler);
+ if (begin == end) return begin;
+
+ // Parse sign.
+ switch (to_ascii(*begin)) {
+ case '+':
+ handler.on_plus();
+ ++begin;
+ break;
+ case '-':
+ handler.on_minus();
+ ++begin;
+ break;
+ case ' ':
+ handler.on_space();
+ ++begin;
+ break;
+ }
+ if (begin == end) return begin;
+
+ if (*begin == '#') {
+ handler.on_hash();
+ if (++begin == end) return begin;
+ }
+
+ // Parse zero flag.
+ if (*begin == '0') {
+ handler.on_zero();
+ if (++begin == end) return begin;
+ }
+
+ begin = parse_width(begin, end, handler);
+ if (begin == end) return begin;
+
+ // Parse precision.
+ if (*begin == '.') {
+ begin = parse_precision(begin, end, handler);
+ }
+
+ // Parse type.
+ if (begin != end && *begin != '}') handler.on_type(*begin++);
+ return begin;
+}
+
+// Return the result via the out param to workaround gcc bug 77539.
+template <bool IS_CONSTEXPR, typename T, typename Ptr = const T*>
+FMT_CONSTEXPR bool find(Ptr first, Ptr last, T value, Ptr& out) {
+ for (out = first; out != last; ++out) {
+ if (*out == value) return true;
+ }
+ return false;
+}
+
+template <>
+inline bool find<false, char>(const char* first, const char* last, char value,
+ const char*& out) {
+ out = static_cast<const char*>(
+ std::memchr(first, value, detail::to_unsigned(last - first)));
+ return out != nullptr;
+}
+
+template <typename Handler, typename Char> struct id_adapter {
+ Handler& handler;
+ int arg_id;
+
+ FMT_CONSTEXPR void operator()() { arg_id = handler.on_arg_id(); }
+ FMT_CONSTEXPR void operator()(int id) { arg_id = handler.on_arg_id(id); }
+ FMT_CONSTEXPR void operator()(basic_string_view<Char> id) {
+ arg_id = handler.on_arg_id(id);
+ }
+ FMT_CONSTEXPR void on_error(const char* message) {
+ handler.on_error(message);
+ }
+};
+
+template <typename Char, typename Handler>
+FMT_CONSTEXPR const Char* parse_replacement_field(const Char* begin,
+ const Char* end,
+ Handler&& handler) {
+ ++begin;
+ if (begin == end) return handler.on_error("invalid format string"), end;
+ if (*begin == '}') {
+ handler.on_replacement_field(handler.on_arg_id(), begin);
+ } else if (*begin == '{') {
+ handler.on_text(begin, begin + 1);
+ } else {
+ auto adapter = id_adapter<Handler, Char>{handler, 0};
+ begin = parse_arg_id(begin, end, adapter);
+ Char c = begin != end ? *begin : Char();
+ if (c == '}') {
+ handler.on_replacement_field(adapter.arg_id, begin);
+ } else if (c == ':') {
+ begin = handler.on_format_specs(adapter.arg_id, begin + 1, end);
+ if (begin == end || *begin != '}')
+ return handler.on_error("unknown format specifier"), end;
+ } else {
+ return handler.on_error("missing '}' in format string"), end;
+ }
+ }
+ return begin + 1;
+}
+
+template <bool IS_CONSTEXPR, typename Char, typename Handler>
+FMT_CONSTEXPR_DECL FMT_INLINE void parse_format_string(
+ basic_string_view<Char> format_str, Handler&& handler) {
+ auto begin = format_str.data();
+ auto end = begin + format_str.size();
+ if (end - begin < 32) {
+ // Use a simple loop instead of memchr for small strings.
+ const Char* p = begin;
+ while (p != end) {
+ auto c = *p++;
+ if (c == '{') {
+ handler.on_text(begin, p - 1);
+ begin = p = parse_replacement_field(p - 1, end, handler);
+ } else if (c == '}') {
+ if (p == end || *p != '}')
+ return handler.on_error("unmatched '}' in format string");
+ handler.on_text(begin, p);
+ begin = ++p;
+ }
+ }
+ handler.on_text(begin, end);
+ return;
+ }
+ struct writer {
+ FMT_CONSTEXPR void operator()(const Char* pbegin, const Char* pend) {
+ if (pbegin == pend) return;
+ for (;;) {
+ const Char* p = nullptr;
+ if (!find<IS_CONSTEXPR>(pbegin, pend, '}', p))
+ return handler_.on_text(pbegin, pend);
+ ++p;
+ if (p == pend || *p != '}')
+ return handler_.on_error("unmatched '}' in format string");
+ handler_.on_text(pbegin, p);
+ pbegin = p + 1;
+ }
+ }
+ Handler& handler_;
+ } write{handler};
+ while (begin != end) {
+ // Doing two passes with memchr (one for '{' and another for '}') is up to
+ // 2.5x faster than the naive one-pass implementation on big format strings.
+ const Char* p = begin;
+ if (*begin != '{' && !find<IS_CONSTEXPR>(begin + 1, end, '{', p))
+ return write(begin, end);
+ write(begin, p);
+ begin = parse_replacement_field(p, end, handler);
+ }
+}
+
+template <typename T, typename ParseContext>
+FMT_CONSTEXPR const typename ParseContext::char_type* parse_format_specs(
+ ParseContext& ctx) {
+ using char_type = typename ParseContext::char_type;
+ using context = buffer_context<char_type>;
+ using mapped_type =
+ conditional_t<detail::mapped_type_constant<T, context>::value !=
+ type::custom_type,
+ decltype(arg_mapper<context>().map(std::declval<T>())), T>;
+ auto f = conditional_t<has_formatter<mapped_type, context>::value,
+ formatter<mapped_type, char_type>,
+ detail::fallback_formatter<T, char_type>>();
+ return f.parse(ctx);
+}
+
+template <typename OutputIt, typename Char, typename Context>
+struct format_handler : detail::error_handler {
+ basic_format_parse_context<Char> parse_context;
+ Context context;
+
+ format_handler(OutputIt out, basic_string_view<Char> str,
+ basic_format_args<Context> format_args, detail::locale_ref loc)
+ : parse_context(str), context(out, format_args, loc) {}
+
+ void on_text(const Char* begin, const Char* end) {
+ auto size = to_unsigned(end - begin);
+ auto out = context.out();
+ auto&& it = reserve(out, size);
+ it = std::copy_n(begin, size, it);
+ context.advance_to(out);
+ }
+
+ int on_arg_id() { return parse_context.next_arg_id(); }
+ int on_arg_id(int id) { return parse_context.check_arg_id(id), id; }
+ int on_arg_id(basic_string_view<Char> id) {
+ int arg_id = context.arg_id(id);
+ if (arg_id < 0) on_error("argument not found");
+ return arg_id;
+ }
+
+ FMT_INLINE void on_replacement_field(int id, const Char*) {
+ auto arg = get_arg(context, id);
+ context.advance_to(visit_format_arg(
+ default_arg_formatter<OutputIt, Char>{context.out(), context.args(),
+ context.locale()},
+ arg));
+ }
+
+ const Char* on_format_specs(int id, const Char* begin, const Char* end) {
+ auto arg = get_arg(context, id);
+ if (arg.type() == type::custom_type) {
+ advance_to(parse_context, begin);
+ visit_format_arg(custom_formatter<Context>(parse_context, context), arg);
+ return parse_context.begin();
+ }
+ auto specs = basic_format_specs<Char>();
+ if (begin + 1 < end && begin[1] == '}' && is_ascii_letter(*begin)) {
+ specs.type = static_cast<char>(*begin++);
+ } else {
+ using parse_context_t = basic_format_parse_context<Char>;
+ specs_checker<specs_handler<parse_context_t, Context>> handler(
+ specs_handler<parse_context_t, Context>(specs, parse_context,
+ context),
+ arg.type());
+ begin = parse_format_specs(begin, end, handler);
+ if (begin == end || *begin != '}')
+ on_error("missing '}' in format string");
+ }
+ context.advance_to(visit_format_arg(
+ arg_formatter<OutputIt, Char>(context, &parse_context, &specs), arg));
+ return begin;
+ }
+};
+
+// A parse context with extra argument id checks. It is only used at compile
+// time because adding checks at runtime would introduce substantial overhead
+// and would be redundant since argument ids are checked when arguments are
+// retrieved anyway.
+template <typename Char, typename ErrorHandler = error_handler>
+class compile_parse_context
+ : public basic_format_parse_context<Char, ErrorHandler> {
+ private:
+ int num_args_;
+ using base = basic_format_parse_context<Char, ErrorHandler>;
+
+ public:
+ explicit FMT_CONSTEXPR compile_parse_context(
+ basic_string_view<Char> format_str, int num_args = max_value<int>(),
+ ErrorHandler eh = {})
+ : base(format_str, eh), num_args_(num_args) {}
+
+ FMT_CONSTEXPR int next_arg_id() {
+ int id = base::next_arg_id();
+ if (id >= num_args_) this->on_error("argument not found");
+ return id;
+ }
+
+ FMT_CONSTEXPR void check_arg_id(int id) {
+ base::check_arg_id(id);
+ if (id >= num_args_) this->on_error("argument not found");
+ }
+ using base::check_arg_id;
+};
+
+template <typename Char, typename ErrorHandler, typename... Args>
+class format_string_checker {
+ public:
+ explicit FMT_CONSTEXPR format_string_checker(
+ basic_string_view<Char> format_str, ErrorHandler eh)
+ : context_(format_str, num_args, eh),
+ parse_funcs_{&parse_format_specs<Args, parse_context_type>...} {}
+
+ FMT_CONSTEXPR void on_text(const Char*, const Char*) {}
+
+ FMT_CONSTEXPR int on_arg_id() { return context_.next_arg_id(); }
+ FMT_CONSTEXPR int on_arg_id(int id) { return context_.check_arg_id(id), id; }
+ FMT_CONSTEXPR int on_arg_id(basic_string_view<Char>) {
+ on_error("compile-time checks don't support named arguments");
+ return 0;
+ }
+
+ FMT_CONSTEXPR void on_replacement_field(int, const Char*) {}
+
+ FMT_CONSTEXPR const Char* on_format_specs(int id, const Char* begin,
+ const Char*) {
+ advance_to(context_, begin);
+ return id < num_args ? parse_funcs_[id](context_) : begin;
+ }
+
+ FMT_CONSTEXPR void on_error(const char* message) {
+ context_.on_error(message);
+ }
+
+ private:
+ using parse_context_type = compile_parse_context<Char, ErrorHandler>;
+ enum { num_args = sizeof...(Args) };
+
+ // Format specifier parsing function.
+ using parse_func = const Char* (*)(parse_context_type&);
+
+ parse_context_type context_;
+ parse_func parse_funcs_[num_args > 0 ? num_args : 1];
+};
+
+// Converts string literals to basic_string_view.
+template <typename Char, size_t N>
+FMT_CONSTEXPR basic_string_view<Char> compile_string_to_view(
+ const Char (&s)[N]) {
+ // Remove trailing null character if needed. Won't be present if this is used
+ // with raw character array (i.e. not defined as a string).
+ return {s,
+ N - ((std::char_traits<Char>::to_int_type(s[N - 1]) == 0) ? 1 : 0)};
+}
+
+// Converts string_view to basic_string_view.
+template <typename Char>
+FMT_CONSTEXPR basic_string_view<Char> compile_string_to_view(
+ const std_string_view<Char>& s) {
+ return {s.data(), s.size()};
+}
+
+#define FMT_STRING_IMPL(s, base) \
+ [] { \
+ /* Use a macro-like name to avoid shadowing warnings. */ \
+ struct FMT_COMPILE_STRING : base { \
+ using char_type = fmt::remove_cvref_t<decltype(s[0])>; \
+ FMT_MAYBE_UNUSED FMT_CONSTEXPR \
+ operator fmt::basic_string_view<char_type>() const { \
+ return fmt::detail::compile_string_to_view<char_type>(s); \
+ } \
+ }; \
+ return FMT_COMPILE_STRING(); \
+ }()
+
+/**
+ \rst
+ Constructs a compile-time format string from a string literal *s*.
+
+ **Example**::
+
+ // A compile-time error because 'd' is an invalid specifier for strings.
+ std::string s = fmt::format(FMT_STRING("{:d}"), "foo");
+ \endrst
+ */
+#define FMT_STRING(s) FMT_STRING_IMPL(s, fmt::compile_string)
+
+template <typename... Args, typename S,
+ enable_if_t<(is_compile_string<S>::value), int>>
+void check_format_string(S format_str) {
+ FMT_CONSTEXPR_DECL auto s = to_string_view(format_str);
+ using checker = format_string_checker<typename S::char_type, error_handler,
+ remove_cvref_t<Args>...>;
+ FMT_CONSTEXPR_DECL bool invalid_format =
+ (parse_format_string<true>(s, checker(s, {})), true);
+ (void)invalid_format;
+}
+
+template <template <typename> class Handler, typename Context>
+void handle_dynamic_spec(int& value, arg_ref<typename Context::char_type> ref,
+ Context& ctx) {
+ switch (ref.kind) {
+ case arg_id_kind::none:
+ break;
+ case arg_id_kind::index:
+ value = detail::get_dynamic_spec<Handler>(ctx.arg(ref.val.index),
+ ctx.error_handler());
+ break;
+ case arg_id_kind::name:
+ value = detail::get_dynamic_spec<Handler>(ctx.arg(ref.val.name),
+ ctx.error_handler());
+ break;
+ }
+}
+
+using format_func = void (*)(detail::buffer<char>&, int, string_view);
+
+FMT_API void format_error_code(buffer<char>& out, int error_code,
+ string_view message) FMT_NOEXCEPT;
+
+FMT_API void report_error(format_func func, int error_code,
+ string_view message) FMT_NOEXCEPT;
+} // namespace detail
+
+template <typename OutputIt, typename Char>
+using arg_formatter FMT_DEPRECATED_ALIAS =
+ detail::arg_formatter<OutputIt, Char>;
+
+/**
+ An error returned by an operating system or a language runtime,
+ for example a file opening error.
+*/
+FMT_CLASS_API
+class FMT_API system_error : public std::runtime_error {
+ private:
+ void init(int err_code, string_view format_str, format_args args);
+
+ protected:
+ int error_code_;
+
+ system_error() : std::runtime_error(""), error_code_(0) {}
+
+ public:
+ /**
+ \rst
+ Constructs a :class:`fmt::system_error` object with a description
+ formatted with `fmt::format_system_error`. *message* and additional
+ arguments passed into the constructor are formatted similarly to
+ `fmt::format`.
+
+ **Example**::
+
+ // This throws a system_error with the description
+ // cannot open file 'madeup': No such file or directory
+ // or similar (system message may vary).
+ const char *filename = "madeup";
+ std::FILE *file = std::fopen(filename, "r");
+ if (!file)
+ throw fmt::system_error(errno, "cannot open file '{}'", filename);
+ \endrst
+ */
+ template <typename... Args>
+ system_error(int error_code, string_view message, const Args&... args)
+ : std::runtime_error("") {
+ init(error_code, message, make_format_args(args...));
+ }
+ system_error(const system_error&) = default;
+ system_error& operator=(const system_error&) = default;
+ system_error(system_error&&) = default;
+ system_error& operator=(system_error&&) = default;
+ ~system_error() FMT_NOEXCEPT FMT_OVERRIDE;
+
+ int error_code() const { return error_code_; }
+};
+
+/**
+ \rst
+ Formats an error returned by an operating system or a language runtime,
+ for example a file opening error, and writes it to *out* in the following
+ form:
+
+ .. parsed-literal::
+ *<message>*: *<system-message>*
+
+ where *<message>* is the passed message and *<system-message>* is
+ the system message corresponding to the error code.
+ *error_code* is a system error code as given by ``errno``.
+ If *error_code* is not a valid error code such as -1, the system message
+ may look like "Unknown error -1" and is platform-dependent.
+ \endrst
+ */
+FMT_API void format_system_error(detail::buffer<char>& out, int error_code,
+ string_view message) FMT_NOEXCEPT;
+
+// Reports a system error without throwing an exception.
+// Can be used to report errors from destructors.
+FMT_API void report_system_error(int error_code,
+ string_view message) FMT_NOEXCEPT;
+
+/** Fast integer formatter. */
+class format_int {
+ private:
+ // Buffer should be large enough to hold all digits (digits10 + 1),
+ // a sign and a null character.
+ enum { buffer_size = std::numeric_limits<unsigned long long>::digits10 + 3 };
+ mutable char buffer_[buffer_size];
+ char* str_;
+
+ template <typename UInt> char* format_unsigned(UInt value) {
+ auto n = static_cast<detail::uint32_or_64_or_128_t<UInt>>(value);
+ return detail::format_decimal(buffer_, n, buffer_size - 1).begin;
+ }
+
+ template <typename Int> char* format_signed(Int value) {
+ auto abs_value = static_cast<detail::uint32_or_64_or_128_t<Int>>(value);
+ bool negative = value < 0;
+ if (negative) abs_value = 0 - abs_value;
+ auto begin = format_unsigned(abs_value);
+ if (negative) *--begin = '-';
+ return begin;
+ }
+
+ public:
+ explicit format_int(int value) : str_(format_signed(value)) {}
+ explicit format_int(long value) : str_(format_signed(value)) {}
+ explicit format_int(long long value) : str_(format_signed(value)) {}
+ explicit format_int(unsigned value) : str_(format_unsigned(value)) {}
+ explicit format_int(unsigned long value) : str_(format_unsigned(value)) {}
+ explicit format_int(unsigned long long value)
+ : str_(format_unsigned(value)) {}
+
+ /** Returns the number of characters written to the output buffer. */
+ size_t size() const {
+ return detail::to_unsigned(buffer_ - str_ + buffer_size - 1);
+ }
+
+ /**
+ Returns a pointer to the output buffer content. No terminating null
+ character is appended.
+ */
+ const char* data() const { return str_; }
+
+ /**
+ Returns a pointer to the output buffer content with terminating null
+ character appended.
+ */
+ const char* c_str() const {
+ buffer_[buffer_size - 1] = '\0';
+ return str_;
+ }
+
+ /**
+ \rst
+ Returns the content of the output buffer as an ``std::string``.
+ \endrst
+ */
+ std::string str() const { return std::string(str_, size()); }
+};
+
+// A formatter specialization for the core types corresponding to detail::type
+// constants.
+template <typename T, typename Char>
+struct formatter<T, Char,
+ enable_if_t<detail::type_constant<T, Char>::value !=
+ detail::type::custom_type>> {
+ FMT_CONSTEXPR formatter() = default;
+
+ // Parses format specifiers stopping either at the end of the range or at the
+ // terminating '}'.
+ template <typename ParseContext>
+ FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+ using handler_type = detail::dynamic_specs_handler<ParseContext>;
+ auto type = detail::type_constant<T, Char>::value;
+ detail::specs_checker<handler_type> handler(handler_type(specs_, ctx),
+ type);
+ auto it = parse_format_specs(ctx.begin(), ctx.end(), handler);
+ auto eh = ctx.error_handler();
+ switch (type) {
+ case detail::type::none_type:
+ FMT_ASSERT(false, "invalid argument type");
+ break;
+ case detail::type::int_type:
+ case detail::type::uint_type:
+ case detail::type::long_long_type:
+ case detail::type::ulong_long_type:
+ case detail::type::int128_type:
+ case detail::type::uint128_type:
+ case detail::type::bool_type:
+ handle_int_type_spec(specs_.type,
+ detail::int_type_checker<decltype(eh)>(eh));
+ break;
+ case detail::type::char_type:
+ handle_char_specs(
+ &specs_, detail::char_specs_checker<decltype(eh)>(specs_.type, eh));
+ break;
+ case detail::type::float_type:
+ if (detail::const_check(FMT_USE_FLOAT))
+ detail::parse_float_type_spec(specs_, eh);
+ else
+ FMT_ASSERT(false, "float support disabled");
+ break;
+ case detail::type::double_type:
+ if (detail::const_check(FMT_USE_DOUBLE))
+ detail::parse_float_type_spec(specs_, eh);
+ else
+ FMT_ASSERT(false, "double support disabled");
+ break;
+ case detail::type::long_double_type:
+ if (detail::const_check(FMT_USE_LONG_DOUBLE))
+ detail::parse_float_type_spec(specs_, eh);
+ else
+ FMT_ASSERT(false, "long double support disabled");
+ break;
+ case detail::type::cstring_type:
+ detail::handle_cstring_type_spec(
+ specs_.type, detail::cstring_type_checker<decltype(eh)>(eh));
+ break;
+ case detail::type::string_type:
+ detail::check_string_type_spec(specs_.type, eh);
+ break;
+ case detail::type::pointer_type:
+ detail::check_pointer_type_spec(specs_.type, eh);
+ break;
+ case detail::type::custom_type:
+ // Custom format specifiers should be checked in parse functions of
+ // formatter specializations.
+ break;
+ }
+ return it;
+ }
+
+ template <typename FormatContext>
+ auto format(const T& val, FormatContext& ctx) -> decltype(ctx.out()) {
+ detail::handle_dynamic_spec<detail::width_checker>(specs_.width,
+ specs_.width_ref, ctx);
+ detail::handle_dynamic_spec<detail::precision_checker>(
+ specs_.precision, specs_.precision_ref, ctx);
+ using af = detail::arg_formatter<typename FormatContext::iterator,
+ typename FormatContext::char_type>;
+ return visit_format_arg(af(ctx, nullptr, &specs_),
+ detail::make_arg<FormatContext>(val));
+ }
+
+ private:
+ detail::dynamic_format_specs<Char> specs_;
+};
+
+#define FMT_FORMAT_AS(Type, Base) \
+ template <typename Char> \
+ struct formatter<Type, Char> : formatter<Base, Char> { \
+ template <typename FormatContext> \
+ auto format(Type const& val, FormatContext& ctx) -> decltype(ctx.out()) { \
+ return formatter<Base, Char>::format(val, ctx); \
+ } \
+ }
+
+FMT_FORMAT_AS(signed char, int);
+FMT_FORMAT_AS(unsigned char, unsigned);
+FMT_FORMAT_AS(short, int);
+FMT_FORMAT_AS(unsigned short, unsigned);
+FMT_FORMAT_AS(long, long long);
+FMT_FORMAT_AS(unsigned long, unsigned long long);
+FMT_FORMAT_AS(Char*, const Char*);
+FMT_FORMAT_AS(std::basic_string<Char>, basic_string_view<Char>);
+FMT_FORMAT_AS(std::nullptr_t, const void*);
+FMT_FORMAT_AS(detail::std_string_view<Char>, basic_string_view<Char>);
+
+template <typename Char>
+struct formatter<void*, Char> : formatter<const void*, Char> {
+ template <typename FormatContext>
+ auto format(void* val, FormatContext& ctx) -> decltype(ctx.out()) {
+ return formatter<const void*, Char>::format(val, ctx);
+ }
+};
+
+template <typename Char, size_t N>
+struct formatter<Char[N], Char> : formatter<basic_string_view<Char>, Char> {
+ template <typename FormatContext>
+ auto format(const Char* val, FormatContext& ctx) -> decltype(ctx.out()) {
+ return formatter<basic_string_view<Char>, Char>::format(val, ctx);
+ }
+};
+
+// A formatter for types known only at run time such as variant alternatives.
+//
+// Usage:
+// using variant = std::variant<int, std::string>;
+// template <>
+// struct formatter<variant>: dynamic_formatter<> {
+// auto format(const variant& v, format_context& ctx) {
+// return visit([&](const auto& val) {
+// return dynamic_formatter<>::format(val, ctx);
+// }, v);
+// }
+// };
+template <typename Char = char> class dynamic_formatter {
+ private:
+ struct null_handler : detail::error_handler {
+ void on_align(align_t) {}
+ void on_plus() {}
+ void on_minus() {}
+ void on_space() {}
+ void on_hash() {}
+ };
+
+ public:
+ template <typename ParseContext>
+ auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+ format_str_ = ctx.begin();
+ // Checks are deferred to formatting time when the argument type is known.
+ detail::dynamic_specs_handler<ParseContext> handler(specs_, ctx);
+ return parse_format_specs(ctx.begin(), ctx.end(), handler);
+ }
+
+ template <typename T, typename FormatContext>
+ auto format(const T& val, FormatContext& ctx) -> decltype(ctx.out()) {
+ handle_specs(ctx);
+ detail::specs_checker<null_handler> checker(
+ null_handler(), detail::mapped_type_constant<T, FormatContext>::value);
+ checker.on_align(specs_.align);
+ switch (specs_.sign) {
+ case sign::none:
+ break;
+ case sign::plus:
+ checker.on_plus();
+ break;
+ case sign::minus:
+ checker.on_minus();
+ break;
+ case sign::space:
+ checker.on_space();
+ break;
+ }
+ if (specs_.alt) checker.on_hash();
+ if (specs_.precision >= 0) checker.end_precision();
+ using af = detail::arg_formatter<typename FormatContext::iterator,
+ typename FormatContext::char_type>;
+ visit_format_arg(af(ctx, nullptr, &specs_),
+ detail::make_arg<FormatContext>(val));
+ return ctx.out();
+ }
+
+ private:
+ template <typename Context> void handle_specs(Context& ctx) {
+ detail::handle_dynamic_spec<detail::width_checker>(specs_.width,
+ specs_.width_ref, ctx);
+ detail::handle_dynamic_spec<detail::precision_checker>(
+ specs_.precision, specs_.precision_ref, ctx);
+ }
+
+ detail::dynamic_format_specs<Char> specs_;
+ const Char* format_str_;
+};
+
+template <typename Char, typename ErrorHandler>
+FMT_CONSTEXPR void advance_to(
+ basic_format_parse_context<Char, ErrorHandler>& ctx, const Char* p) {
+ ctx.advance_to(ctx.begin() + (p - &*ctx.begin()));
+}
+
+/**
+ \rst
+ Converts ``p`` to ``const void*`` for pointer formatting.
+
+ **Example**::
+
+ auto s = fmt::format("{}", fmt::ptr(p));
+ \endrst
+ */
+template <typename T> inline const void* ptr(const T* p) { return p; }
+template <typename T> inline const void* ptr(const std::unique_ptr<T>& p) {
+ return p.get();
+}
+template <typename T> inline const void* ptr(const std::shared_ptr<T>& p) {
+ return p.get();
+}
+
+class bytes {
+ private:
+ string_view data_;
+ friend struct formatter<bytes>;
+
+ public:
+ explicit bytes(string_view data) : data_(data) {}
+};
+
+template <> struct formatter<bytes> {
+ private:
+ detail::dynamic_format_specs<char> specs_;
+
+ public:
+ template <typename ParseContext>
+ FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
+ using handler_type = detail::dynamic_specs_handler<ParseContext>;
+ detail::specs_checker<handler_type> handler(handler_type(specs_, ctx),
+ detail::type::string_type);
+ auto it = parse_format_specs(ctx.begin(), ctx.end(), handler);
+ detail::check_string_type_spec(specs_.type, ctx.error_handler());
+ return it;
+ }
+
+ template <typename FormatContext>
+ auto format(bytes b, FormatContext& ctx) -> decltype(ctx.out()) {
+ detail::handle_dynamic_spec<detail::width_checker>(specs_.width,
+ specs_.width_ref, ctx);
+ detail::handle_dynamic_spec<detail::precision_checker>(
+ specs_.precision, specs_.precision_ref, ctx);
+ return detail::write_bytes(ctx.out(), b.data_, specs_);
+ }
+};
+
+template <typename It, typename Sentinel, typename Char>
+struct arg_join : detail::view {
+ It begin;
+ Sentinel end;
+ basic_string_view<Char> sep;
+
+ arg_join(It b, Sentinel e, basic_string_view<Char> s)
+ : begin(b), end(e), sep(s) {}
+};
+
+template <typename It, typename Sentinel, typename Char>
+struct formatter<arg_join<It, Sentinel, Char>, Char>
+ : formatter<typename std::iterator_traits<It>::value_type, Char> {
+ template <typename FormatContext>
+ auto format(const arg_join<It, Sentinel, Char>& value, FormatContext& ctx)
+ -> decltype(ctx.out()) {
+ using base = formatter<typename std::iterator_traits<It>::value_type, Char>;
+ auto it = value.begin;
+ auto out = ctx.out();
+ if (it != value.end) {
+ out = base::format(*it++, ctx);
+ while (it != value.end) {
+ out = std::copy(value.sep.begin(), value.sep.end(), out);
+ ctx.advance_to(out);
+ out = base::format(*it++, ctx);
+ }
+ }
+ return out;
+ }
+};
+
+/**
+ Returns an object that formats the iterator range `[begin, end)` with elements
+ separated by `sep`.
+ */
+template <typename It, typename Sentinel>
+arg_join<It, Sentinel, char> join(It begin, Sentinel end, string_view sep) {
+ return {begin, end, sep};
+}
+
+template <typename It, typename Sentinel>
+arg_join<It, Sentinel, wchar_t> join(It begin, Sentinel end, wstring_view sep) {
+ return {begin, end, sep};
+}
+
+/**
+ \rst
+ Returns an object that formats `range` with elements separated by `sep`.
+
+ **Example**::
+
+ std::vector<int> v = {1, 2, 3};
+ fmt::print("{}", fmt::join(v, ", "));
+ // Output: "1, 2, 3"
+
+ ``fmt::join`` applies passed format specifiers to the range elements::
+
+ fmt::print("{:02}", fmt::join(v, ", "));
+ // Output: "01, 02, 03"
+ \endrst
+ */
+template <typename Range>
+arg_join<detail::iterator_t<Range>, detail::sentinel_t<Range>, char> join(
+ Range&& range, string_view sep) {
+ return join(std::begin(range), std::end(range), sep);
+}
+
+template <typename Range>
+arg_join<detail::iterator_t<Range>, detail::sentinel_t<Range>, wchar_t> join(
+ Range&& range, wstring_view sep) {
+ return join(std::begin(range), std::end(range), sep);
+}
+
+/**
+ \rst
+ Converts *value* to ``std::string`` using the default format for type *T*.
+
+ **Example**::
+
+ #include <fmt/format.h>
+
+ std::string answer = fmt::to_string(42);
+ \endrst
+ */
+template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value)>
+inline std::string to_string(const T& value) {
+ std::string result;
+ detail::write<char>(std::back_inserter(result), value);
+ return result;
+}
+
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+inline std::string to_string(T value) {
+ // The buffer should be large enough to store the number including the sign or
+ // "false" for bool.
+ constexpr int max_size = detail::digits10<T>() + 2;
+ char buffer[max_size > 5 ? static_cast<unsigned>(max_size) : 5];
+ char* begin = buffer;
+ return std::string(begin, detail::write<char>(begin, value));
+}
+
+/**
+ Converts *value* to ``std::wstring`` using the default format for type *T*.
+ */
+template <typename T> inline std::wstring to_wstring(const T& value) {
+ return format(L"{}", value);
+}
+
+template <typename Char, size_t SIZE>
+std::basic_string<Char> to_string(const basic_memory_buffer<Char, SIZE>& buf) {
+ auto size = buf.size();
+ detail::assume(size < std::basic_string<Char>().max_size());
+ return std::basic_string<Char>(buf.data(), size);
+}
+
+template <typename Char>
+void detail::vformat_to(
+ detail::buffer<Char>& buf, basic_string_view<Char> format_str,
+ basic_format_args<buffer_context<type_identity_t<Char>>> args,
+ detail::locale_ref loc) {
+ using iterator = typename buffer_context<Char>::iterator;
+ auto out = buffer_appender<Char>(buf);
+ if (format_str.size() == 2 && equal2(format_str.data(), "{}")) {
+ auto arg = args.get(0);
+ if (!arg) error_handler().on_error("argument not found");
+ visit_format_arg(default_arg_formatter<iterator, Char>{out, args, loc},
+ arg);
+ return;
+ }
+ format_handler<iterator, Char, buffer_context<Char>> h(out, format_str, args,
+ loc);
+ parse_format_string<false>(format_str, h);
+}
+
+#ifndef FMT_HEADER_ONLY
+extern template void detail::vformat_to(detail::buffer<char>&, string_view,
+ basic_format_args<format_context>,
+ detail::locale_ref);
+namespace detail {
+
+extern template FMT_API std::string grouping_impl<char>(locale_ref loc);
+extern template FMT_API std::string grouping_impl<wchar_t>(locale_ref loc);
+extern template FMT_API char thousands_sep_impl<char>(locale_ref loc);
+extern template FMT_API wchar_t thousands_sep_impl<wchar_t>(locale_ref loc);
+extern template FMT_API char decimal_point_impl(locale_ref loc);
+extern template FMT_API wchar_t decimal_point_impl(locale_ref loc);
+extern template int format_float<double>(double value, int precision,
+ float_specs specs, buffer<char>& buf);
+extern template int format_float<long double>(long double value, int precision,
+ float_specs specs,
+ buffer<char>& buf);
+int snprintf_float(float value, int precision, float_specs specs,
+ buffer<char>& buf) = delete;
+extern template int snprintf_float<double>(double value, int precision,
+ float_specs specs,
+ buffer<char>& buf);
+extern template int snprintf_float<long double>(long double value,
+ int precision,
+ float_specs specs,
+ buffer<char>& buf);
+} // namespace detail
+#endif
+
+template <typename S, typename Char = char_t<S>,
+ FMT_ENABLE_IF(detail::is_string<S>::value)>
+inline void vformat_to(
+ detail::buffer<Char>& buf, const S& format_str,
+ basic_format_args<FMT_BUFFER_CONTEXT(type_identity_t<Char>)> args) {
+ return detail::vformat_to(buf, to_string_view(format_str), args);
+}
+
+template <typename S, typename... Args, size_t SIZE = inline_buffer_size,
+ typename Char = enable_if_t<detail::is_string<S>::value, char_t<S>>>
+inline typename buffer_context<Char>::iterator format_to(
+ basic_memory_buffer<Char, SIZE>& buf, const S& format_str, Args&&... args) {
+ const auto& vargs = fmt::make_args_checked<Args...>(format_str, args...);
+ detail::vformat_to(buf, to_string_view(format_str), vargs);
+ return detail::buffer_appender<Char>(buf);
+}
+
+template <typename OutputIt, typename Char = char>
+using format_context_t = basic_format_context<OutputIt, Char>;
+
+template <typename OutputIt, typename Char = char>
+using format_args_t = basic_format_args<format_context_t<OutputIt, Char>>;
+
+template <typename OutputIt, typename Char = typename OutputIt::value_type>
+using format_to_n_context FMT_DEPRECATED_ALIAS = buffer_context<Char>;
+
+template <typename OutputIt, typename Char = typename OutputIt::value_type>
+using format_to_n_args FMT_DEPRECATED_ALIAS =
+ basic_format_args<buffer_context<Char>>;
+
+template <typename OutputIt, typename Char, typename... Args>
+FMT_DEPRECATED format_arg_store<buffer_context<Char>, Args...>
+make_format_to_n_args(const Args&... args) {
+ return format_arg_store<buffer_context<Char>, Args...>(args...);
+}
+
+template <typename Char, enable_if_t<(!std::is_same<Char, char>::value), int>>
+std::basic_string<Char> detail::vformat(
+ basic_string_view<Char> format_str,
+ basic_format_args<buffer_context<type_identity_t<Char>>> args) {
+ basic_memory_buffer<Char> buffer;
+ detail::vformat_to(buffer, format_str, args);
+ return to_string(buffer);
+}
+
+template <typename Char, FMT_ENABLE_IF(std::is_same<Char, wchar_t>::value)>
+void vprint(std::FILE* f, basic_string_view<Char> format_str,
+ wformat_args args) {
+ wmemory_buffer buffer;
+ detail::vformat_to(buffer, format_str, args);
+ buffer.push_back(L'\0');
+ if (std::fputws(buffer.data(), f) == -1)
+ FMT_THROW(system_error(errno, "cannot write to file"));
+}
+
+template <typename Char, FMT_ENABLE_IF(std::is_same<Char, wchar_t>::value)>
+void vprint(basic_string_view<Char> format_str, wformat_args args) {
+ vprint(stdout, format_str, args);
+}
+
+#if FMT_USE_USER_DEFINED_LITERALS
+namespace detail {
+
+# if FMT_USE_UDL_TEMPLATE
+template <typename Char, Char... CHARS> class udl_formatter {
+ public:
+ template <typename... Args>
+ std::basic_string<Char> operator()(Args&&... args) const {
+ static FMT_CONSTEXPR_DECL Char s[] = {CHARS..., '\0'};
+ return format(FMT_STRING(s), std::forward<Args>(args)...);
+ }
+};
+# else
+template <typename Char> struct udl_formatter {
+ basic_string_view<Char> str;
+
+ template <typename... Args>
+ std::basic_string<Char> operator()(Args&&... args) const {
+ return format(str, std::forward<Args>(args)...);
+ }
+};
+# endif // FMT_USE_UDL_TEMPLATE
+
+template <typename Char> struct udl_arg {
+ const Char* str;
+
+ template <typename T> named_arg<Char, T> operator=(T&& value) const {
+ return {str, std::forward<T>(value)};
+ }
+};
+} // namespace detail
+
+inline namespace literals {
+# if FMT_USE_UDL_TEMPLATE
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wpedantic"
+# if FMT_CLANG_VERSION
+# pragma GCC diagnostic ignored "-Wgnu-string-literal-operator-template"
+# endif
+template <typename Char, Char... CHARS>
+FMT_CONSTEXPR detail::udl_formatter<Char, CHARS...> operator""_format() {
+ return {};
+}
+# pragma GCC diagnostic pop
+# else
+/**
+ \rst
+ User-defined literal equivalent of :func:`fmt::format`.
+
+ **Example**::
+
+ using namespace fmt::literals;
+ std::string message = "The answer is {}"_format(42);
+ \endrst
+ */
+FMT_CONSTEXPR detail::udl_formatter<char> operator"" _format(const char* s,
+ size_t n) {
+ return {{s, n}};
+}
+FMT_CONSTEXPR detail::udl_formatter<wchar_t> operator"" _format(
+ const wchar_t* s, size_t n) {
+ return {{s, n}};
+}
+# endif // FMT_USE_UDL_TEMPLATE
+
+/**
+ \rst
+ User-defined literal equivalent of :func:`fmt::arg`.
+
+ **Example**::
+
+ using namespace fmt::literals;
+ fmt::print("Elapsed time: {s:.2f} seconds", "s"_a=1.23);
+ \endrst
+ */
+FMT_CONSTEXPR detail::udl_arg<char> operator"" _a(const char* s, size_t) {
+ return {s};
+}
+FMT_CONSTEXPR detail::udl_arg<wchar_t> operator"" _a(const wchar_t* s, size_t) {
+ return {s};
+}
+} // namespace literals
+#endif // FMT_USE_USER_DEFINED_LITERALS
+FMT_END_NAMESPACE
+
+#ifdef FMT_HEADER_ONLY
+# define FMT_FUNC inline
+# include "format-inl.h"
+#else
+# define FMT_FUNC
+#endif
+
+#endif // FMT_FORMAT_H_