--- /dev/null
+/*
+ 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 <cmath> // std::signbit
+#include <cstdint> // uint32_t
+#include <cstring> // std::memcpy
+#include <initializer_list> // std::initializer_list
+#include <limits> // std::numeric_limits
+#include <memory> // std::uninitialized_copy
+#include <stdexcept> // std::runtime_error
+#include <system_error> // std::system_error
+
+#ifdef __cpp_lib_bit_cast
+# include <bit> // std::bit_cast
+#endif
+
+#include "core.h"
+
+#if defined __cpp_inline_variables && __cpp_inline_variables >= 201606L
+# define FMT_INLINE_VARIABLE inline
+#else
+# define FMT_INLINE_VARIABLE
+#endif
+
+#if FMT_HAS_CPP17_ATTRIBUTE(fallthrough)
+# define FMT_FALLTHROUGH [[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
+
+#ifndef FMT_DEPRECATED
+# if FMT_HAS_CPP14_ATTRIBUTE(deprecated) || FMT_MSC_VERSION >= 1900
+# define FMT_DEPRECATED [[deprecated]]
+# else
+# if (defined(__GNUC__) && !defined(__LCC__)) || defined(__clang__)
+# define FMT_DEPRECATED __attribute__((deprecated))
+# elif FMT_MSC_VERSION
+# define FMT_DEPRECATED __declspec(deprecated)
+# else
+# define FMT_DEPRECATED /* deprecated */
+# endif
+# endif
+#endif
+
+#ifndef FMT_NO_UNIQUE_ADDRESS
+# if FMT_CPLUSPLUS >= 202002L
+# if FMT_HAS_CPP_ATTRIBUTE(no_unique_address)
+# define FMT_NO_UNIQUE_ADDRESS [[no_unique_address]]
+// VS2019 v16.10 and later except clang-cl (https://reviews.llvm.org/D110485)
+# elif (FMT_MSC_VERSION >= 1929) && !FMT_CLANG_VERSION
+# define FMT_NO_UNIQUE_ADDRESS [[msvc::no_unique_address]]
+# endif
+# endif
+#endif
+#ifndef FMT_NO_UNIQUE_ADDRESS
+# define FMT_NO_UNIQUE_ADDRESS
+#endif
+
+// Visibility when compiled as a shared library/object.
+#if defined(FMT_LIB_EXPORT) || defined(FMT_SHARED)
+# define FMT_SO_VISIBILITY(value) FMT_VISIBILITY(value)
+#else
+# define FMT_SO_VISIBILITY(value)
+#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
+
+#ifndef FMT_THROW
+# if FMT_EXCEPTIONS
+# if FMT_MSC_VERSION || defined(__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) \
+ ::fmt::detail::assert_fail(__FILE__, __LINE__, (x).what())
+# 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_MAYBE_UNUSED
+# if FMT_HAS_CPP17_ATTRIBUTE(maybe_unused)
+# define FMT_MAYBE_UNUSED [[maybe_unused]]
+# else
+# define FMT_MAYBE_UNUSED
+# endif
+#endif
+
+#ifndef FMT_USE_USER_DEFINED_LITERALS
+// EDG based compilers (Intel, NVIDIA, Elbrus, etc), GCC and MSVC support UDLs.
+//
+// GCC before 4.9 requires a space in `operator"" _a` which is invalid in later
+// compiler versions.
+# if (FMT_HAS_FEATURE(cxx_user_literals) || FMT_GCC_VERSION >= 409 || \
+ FMT_MSC_VERSION >= 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
+
+// Defining FMT_REDUCE_INT_INSTANTIATIONS to 1, will reduce the number of
+// integer formatter template instantiations 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_MSC_VERSION
+# if FMT_HAS_BUILTIN(__builtin_clz) || FMT_GCC_VERSION || FMT_ICC_VERSION
+# define FMT_BUILTIN_CLZ(n) __builtin_clz(n)
+# endif
+# if FMT_HAS_BUILTIN(__builtin_clzll) || FMT_GCC_VERSION || FMT_ICC_VERSION
+# define FMT_BUILTIN_CLZLL(n) __builtin_clzll(n)
+# endif
+#endif
+
+// __builtin_ctz is broken in Intel Compiler Classic on Windows:
+// https://github.com/fmtlib/fmt/issues/2510.
+#ifndef __ICL
+# if FMT_HAS_BUILTIN(__builtin_ctz) || FMT_GCC_VERSION || FMT_ICC_VERSION || \
+ defined(__NVCOMPILER)
+# define FMT_BUILTIN_CTZ(n) __builtin_ctz(n)
+# endif
+# if FMT_HAS_BUILTIN(__builtin_ctzll) || FMT_GCC_VERSION || \
+ FMT_ICC_VERSION || defined(__NVCOMPILER)
+# define FMT_BUILTIN_CTZLL(n) __builtin_ctzll(n)
+# endif
+#endif
+
+#if FMT_MSC_VERSION
+# 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_VERSION && !defined(FMT_BUILTIN_CLZLL) && \
+ !defined(FMT_BUILTIN_CTZLL)
+FMT_BEGIN_NAMESPACE
+namespace detail {
+// Avoid Clang with Microsoft CodeGen's -Wunknown-pragmas warning.
+# if !defined(__clang__)
+# pragma intrinsic(_BitScanForward)
+# pragma intrinsic(_BitScanReverse)
+# if defined(_WIN64)
+# pragma intrinsic(_BitScanForward64)
+# pragma intrinsic(_BitScanReverse64)
+# endif
+# endif
+
+inline auto clz(uint32_t x) -> int {
+ 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_MSC_WARNING(suppress : 6102)
+ return 31 ^ static_cast<int>(r);
+}
+# define FMT_BUILTIN_CLZ(n) detail::clz(n)
+
+inline auto clzll(uint64_t x) -> int {
+ 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 ^ static_cast<int>(r + 32);
+ // Scan the low 32 bits.
+ _BitScanReverse(&r, static_cast<uint32_t>(x));
+# endif
+ FMT_ASSERT(x != 0, "");
+ FMT_MSC_WARNING(suppress : 6102) // Suppress a bogus static analysis warning.
+ return 63 ^ static_cast<int>(r);
+}
+# define FMT_BUILTIN_CLZLL(n) detail::clzll(n)
+
+inline auto ctz(uint32_t x) -> int {
+ unsigned long r = 0;
+ _BitScanForward(&r, x);
+ FMT_ASSERT(x != 0, "");
+ FMT_MSC_WARNING(suppress : 6102) // Suppress a bogus static analysis warning.
+ return static_cast<int>(r);
+}
+# define FMT_BUILTIN_CTZ(n) detail::ctz(n)
+
+inline auto ctzll(uint64_t x) -> int {
+ unsigned long r = 0;
+ FMT_ASSERT(x != 0, "");
+ FMT_MSC_WARNING(suppress : 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
+
+FMT_BEGIN_NAMESPACE
+namespace detail {
+
+FMT_CONSTEXPR inline void abort_fuzzing_if(bool condition) {
+ ignore_unused(condition);
+#ifdef FMT_FUZZ
+ if (condition) throw std::runtime_error("fuzzing limit reached");
+#endif
+}
+
+template <typename CharT, CharT... C> struct string_literal {
+ static constexpr CharT value[sizeof...(C)] = {C...};
+ constexpr operator basic_string_view<CharT>() const {
+ return {value, sizeof...(C)};
+ }
+};
+
+#if FMT_CPLUSPLUS < 201703L
+template <typename CharT, CharT... C>
+constexpr CharT string_literal<CharT, C...>::value[sizeof...(C)];
+#endif
+
+// Implementation of std::bit_cast for pre-C++20.
+template <typename To, typename From, FMT_ENABLE_IF(sizeof(To) == sizeof(From))>
+FMT_CONSTEXPR20 auto bit_cast(const From& from) -> To {
+#ifdef __cpp_lib_bit_cast
+ if (is_constant_evaluated()) return std::bit_cast<To>(from);
+#endif
+ auto to = To();
+ // The cast suppresses a bogus -Wclass-memaccess on GCC.
+ std::memcpy(static_cast<void*>(&to), &from, sizeof(to));
+ return to;
+}
+
+inline auto is_big_endian() -> bool {
+#ifdef _WIN32
+ return false;
+#elif defined(__BIG_ENDIAN__)
+ return true;
+#elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__)
+ return __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__;
+#else
+ struct bytes {
+ char data[sizeof(int)];
+ };
+ return bit_cast<bytes>(1).data[0] == 0;
+#endif
+}
+
+class uint128_fallback {
+ private:
+ uint64_t lo_, hi_;
+
+ public:
+ constexpr uint128_fallback(uint64_t hi, uint64_t lo) : lo_(lo), hi_(hi) {}
+ constexpr uint128_fallback(uint64_t value = 0) : lo_(value), hi_(0) {}
+
+ constexpr auto high() const noexcept -> uint64_t { return hi_; }
+ constexpr auto low() const noexcept -> uint64_t { return lo_; }
+
+ template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+ constexpr explicit operator T() const {
+ return static_cast<T>(lo_);
+ }
+
+ friend constexpr auto operator==(const uint128_fallback& lhs,
+ const uint128_fallback& rhs) -> bool {
+ return lhs.hi_ == rhs.hi_ && lhs.lo_ == rhs.lo_;
+ }
+ friend constexpr auto operator!=(const uint128_fallback& lhs,
+ const uint128_fallback& rhs) -> bool {
+ return !(lhs == rhs);
+ }
+ friend constexpr auto operator>(const uint128_fallback& lhs,
+ const uint128_fallback& rhs) -> bool {
+ return lhs.hi_ != rhs.hi_ ? lhs.hi_ > rhs.hi_ : lhs.lo_ > rhs.lo_;
+ }
+ friend constexpr auto operator|(const uint128_fallback& lhs,
+ const uint128_fallback& rhs)
+ -> uint128_fallback {
+ return {lhs.hi_ | rhs.hi_, lhs.lo_ | rhs.lo_};
+ }
+ friend constexpr auto operator&(const uint128_fallback& lhs,
+ const uint128_fallback& rhs)
+ -> uint128_fallback {
+ return {lhs.hi_ & rhs.hi_, lhs.lo_ & rhs.lo_};
+ }
+ friend constexpr auto operator~(const uint128_fallback& n)
+ -> uint128_fallback {
+ return {~n.hi_, ~n.lo_};
+ }
+ friend auto operator+(const uint128_fallback& lhs,
+ const uint128_fallback& rhs) -> uint128_fallback {
+ auto result = uint128_fallback(lhs);
+ result += rhs;
+ return result;
+ }
+ friend auto operator*(const uint128_fallback& lhs, uint32_t rhs)
+ -> uint128_fallback {
+ FMT_ASSERT(lhs.hi_ == 0, "");
+ uint64_t hi = (lhs.lo_ >> 32) * rhs;
+ uint64_t lo = (lhs.lo_ & ~uint32_t()) * rhs;
+ uint64_t new_lo = (hi << 32) + lo;
+ return {(hi >> 32) + (new_lo < lo ? 1 : 0), new_lo};
+ }
+ friend auto operator-(const uint128_fallback& lhs, uint64_t rhs)
+ -> uint128_fallback {
+ return {lhs.hi_ - (lhs.lo_ < rhs ? 1 : 0), lhs.lo_ - rhs};
+ }
+ FMT_CONSTEXPR auto operator>>(int shift) const -> uint128_fallback {
+ if (shift == 64) return {0, hi_};
+ if (shift > 64) return uint128_fallback(0, hi_) >> (shift - 64);
+ return {hi_ >> shift, (hi_ << (64 - shift)) | (lo_ >> shift)};
+ }
+ FMT_CONSTEXPR auto operator<<(int shift) const -> uint128_fallback {
+ if (shift == 64) return {lo_, 0};
+ if (shift > 64) return uint128_fallback(lo_, 0) << (shift - 64);
+ return {hi_ << shift | (lo_ >> (64 - shift)), (lo_ << shift)};
+ }
+ FMT_CONSTEXPR auto operator>>=(int shift) -> uint128_fallback& {
+ return *this = *this >> shift;
+ }
+ FMT_CONSTEXPR void operator+=(uint128_fallback n) {
+ uint64_t new_lo = lo_ + n.lo_;
+ uint64_t new_hi = hi_ + n.hi_ + (new_lo < lo_ ? 1 : 0);
+ FMT_ASSERT(new_hi >= hi_, "");
+ lo_ = new_lo;
+ hi_ = new_hi;
+ }
+ FMT_CONSTEXPR void operator&=(uint128_fallback n) {
+ lo_ &= n.lo_;
+ hi_ &= n.hi_;
+ }
+
+ FMT_CONSTEXPR20 auto operator+=(uint64_t n) noexcept -> uint128_fallback& {
+ if (is_constant_evaluated()) {
+ lo_ += n;
+ hi_ += (lo_ < n ? 1 : 0);
+ return *this;
+ }
+#if FMT_HAS_BUILTIN(__builtin_addcll) && !defined(__ibmxl__)
+ unsigned long long carry;
+ lo_ = __builtin_addcll(lo_, n, 0, &carry);
+ hi_ += carry;
+#elif FMT_HAS_BUILTIN(__builtin_ia32_addcarryx_u64) && !defined(__ibmxl__)
+ unsigned long long result;
+ auto carry = __builtin_ia32_addcarryx_u64(0, lo_, n, &result);
+ lo_ = result;
+ hi_ += carry;
+#elif defined(_MSC_VER) && defined(_M_X64)
+ auto carry = _addcarry_u64(0, lo_, n, &lo_);
+ _addcarry_u64(carry, hi_, 0, &hi_);
+#else
+ lo_ += n;
+ hi_ += (lo_ < n ? 1 : 0);
+#endif
+ return *this;
+ }
+};
+
+using uint128_t = conditional_t<FMT_USE_INT128, uint128_opt, uint128_fallback>;
+
+#ifdef UINTPTR_MAX
+using uintptr_t = ::uintptr_t;
+#else
+using uintptr_t = uint128_t;
+#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 auto max_value() -> T {
+ return (std::numeric_limits<T>::max)();
+}
+template <typename T> constexpr auto num_bits() -> int {
+ return std::numeric_limits<T>::digits;
+}
+// std::numeric_limits<T>::digits may return 0 for 128-bit ints.
+template <> constexpr auto num_bits<int128_opt>() -> int { return 128; }
+template <> constexpr auto num_bits<uint128_t>() -> int { return 128; }
+
+// A heterogeneous bit_cast used for converting 96-bit long double to uint128_t
+// and 128-bit pointers to uint128_fallback.
+template <typename To, typename From, FMT_ENABLE_IF(sizeof(To) > sizeof(From))>
+inline auto bit_cast(const From& from) -> To {
+ constexpr auto size = static_cast<int>(sizeof(From) / sizeof(unsigned));
+ struct data_t {
+ unsigned value[static_cast<unsigned>(size)];
+ } data = bit_cast<data_t>(from);
+ auto result = To();
+ if (const_check(is_big_endian())) {
+ for (int i = 0; i < size; ++i)
+ result = (result << num_bits<unsigned>()) | data.value[i];
+ } else {
+ for (int i = size - 1; i >= 0; --i)
+ result = (result << num_bits<unsigned>()) | data.value[i];
+ }
+ return result;
+}
+
+template <typename UInt>
+FMT_CONSTEXPR20 inline auto countl_zero_fallback(UInt n) -> int {
+ int lz = 0;
+ constexpr UInt msb_mask = static_cast<UInt>(1) << (num_bits<UInt>() - 1);
+ for (; (n & msb_mask) == 0; n <<= 1) lz++;
+ return lz;
+}
+
+FMT_CONSTEXPR20 inline auto countl_zero(uint32_t n) -> int {
+#ifdef FMT_BUILTIN_CLZ
+ if (!is_constant_evaluated()) return FMT_BUILTIN_CLZ(n);
+#endif
+ return countl_zero_fallback(n);
+}
+
+FMT_CONSTEXPR20 inline auto countl_zero(uint64_t n) -> int {
+#ifdef FMT_BUILTIN_CLZLL
+ if (!is_constant_evaluated()) return FMT_BUILTIN_CLZLL(n);
+#endif
+ return countl_zero_fallback(n);
+}
+
+FMT_INLINE void assume(bool condition) {
+ (void)condition;
+#if FMT_HAS_BUILTIN(__builtin_assume) && !FMT_ICC_VERSION
+ __builtin_assume(condition);
+#elif FMT_GCC_VERSION
+ if (!condition) __builtin_unreachable();
+#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 auto get_data(std::basic_string<Char>& s) -> Char* {
+ return &s[0];
+}
+template <typename Container>
+inline auto get_data(Container& c) -> typename Container::value_type* {
+ return c.data();
+}
+
+// Attempts to reserve space for n extra characters in the output range.
+// Returns a pointer to the reserved range or a reference to it.
+template <typename Container, FMT_ENABLE_IF(is_contiguous<Container>::value)>
+#if FMT_CLANG_VERSION >= 307 && !FMT_ICC_VERSION
+__attribute__((no_sanitize("undefined")))
+#endif
+inline auto
+reserve(std::back_insert_iterator<Container> it, size_t n) ->
+ typename Container::value_type* {
+ Container& c = get_container(it);
+ size_t size = c.size();
+ c.resize(size + n);
+ return get_data(c) + size;
+}
+
+template <typename T>
+inline auto reserve(buffer_appender<T> it, size_t n) -> buffer_appender<T> {
+ buffer<T>& buf = get_container(it);
+ buf.try_reserve(buf.size() + n);
+ return it;
+}
+
+template <typename Iterator>
+constexpr auto reserve(Iterator& it, size_t) -> Iterator& {
+ return it;
+}
+
+template <typename OutputIt>
+using reserve_iterator =
+ remove_reference_t<decltype(reserve(std::declval<OutputIt&>(), 0))>;
+
+template <typename T, typename OutputIt>
+constexpr auto to_pointer(OutputIt, size_t) -> T* {
+ return nullptr;
+}
+template <typename T> auto to_pointer(buffer_appender<T> it, size_t n) -> T* {
+ 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 auto base_iterator(std::back_insert_iterator<Container> it,
+ typename Container::value_type*)
+ -> std::back_insert_iterator<Container> {
+ return it;
+}
+
+template <typename Iterator>
+constexpr auto base_iterator(Iterator, Iterator it) -> Iterator {
+ return it;
+}
+
+// <algorithm> is spectacularly slow to compile in C++20 so use a simple fill_n
+// instead (#1998).
+template <typename OutputIt, typename Size, typename T>
+FMT_CONSTEXPR auto fill_n(OutputIt out, Size count, const T& value)
+ -> OutputIt {
+ for (Size i = 0; i < count; ++i) *out++ = value;
+ return out;
+}
+template <typename T, typename Size>
+FMT_CONSTEXPR20 auto fill_n(T* out, Size count, char value) -> T* {
+ if (is_constant_evaluated()) {
+ return fill_n<T*, Size, T>(out, count, value);
+ }
+ std::memset(out, value, to_unsigned(count));
+ return out + count;
+}
+
+#ifdef __cpp_char8_t
+using char8_type = char8_t;
+#else
+enum char8_type : unsigned char {};
+#endif
+
+template <typename OutChar, typename InputIt, typename OutputIt>
+FMT_CONSTEXPR FMT_NOINLINE auto copy_str_noinline(InputIt begin, InputIt end,
+ OutputIt out) -> OutputIt {
+ return copy_str<OutChar>(begin, end, out);
+}
+
+// A public domain branchless UTF-8 decoder by Christopher Wellons:
+// https://github.com/skeeto/branchless-utf8
+/* Decode the next character, c, from s, reporting errors in e.
+ *
+ * Since this is a branchless decoder, four bytes will be read from the
+ * buffer regardless of the actual length of the next character. This
+ * means the buffer _must_ have at least three bytes of zero padding
+ * following the end of the data stream.
+ *
+ * Errors are reported in e, which will be non-zero if the parsed
+ * character was somehow invalid: invalid byte sequence, non-canonical
+ * encoding, or a surrogate half.
+ *
+ * The function returns a pointer to the next character. When an error
+ * occurs, this pointer will be a guess that depends on the particular
+ * error, but it will always advance at least one byte.
+ */
+FMT_CONSTEXPR inline auto utf8_decode(const char* s, uint32_t* c, int* e)
+ -> const char* {
+ constexpr const int masks[] = {0x00, 0x7f, 0x1f, 0x0f, 0x07};
+ constexpr const uint32_t mins[] = {4194304, 0, 128, 2048, 65536};
+ constexpr const int shiftc[] = {0, 18, 12, 6, 0};
+ constexpr const int shifte[] = {0, 6, 4, 2, 0};
+
+ int len = "\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"
+ [static_cast<unsigned char>(*s) >> 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.
+ const char* next = s + len + !len;
+
+ using uchar = unsigned char;
+
+ // Assume a four-byte character and load four bytes. Unused bits are
+ // shifted out.
+ *c = uint32_t(uchar(s[0]) & masks[len]) << 18;
+ *c |= uint32_t(uchar(s[1]) & 0x3f) << 12;
+ *c |= uint32_t(uchar(s[2]) & 0x3f) << 6;
+ *c |= uint32_t(uchar(s[3]) & 0x3f) << 0;
+ *c >>= shiftc[len];
+
+ // Accumulate the various error conditions.
+ *e = (*c < mins[len]) << 6; // non-canonical encoding
+ *e |= ((*c >> 11) == 0x1b) << 7; // surrogate half?
+ *e |= (*c > 0x10FFFF) << 8; // out of range?
+ *e |= (uchar(s[1]) & 0xc0) >> 2;
+ *e |= (uchar(s[2]) & 0xc0) >> 4;
+ *e |= uchar(s[3]) >> 6;
+ *e ^= 0x2a; // top two bits of each tail byte correct?
+ *e >>= shifte[len];
+
+ return next;
+}
+
+constexpr FMT_INLINE_VARIABLE uint32_t invalid_code_point = ~uint32_t();
+
+// Invokes f(cp, sv) for every code point cp in s with sv being the string view
+// corresponding to the code point. cp is invalid_code_point on error.
+template <typename F>
+FMT_CONSTEXPR void for_each_codepoint(string_view s, F f) {
+ auto decode = [f](const char* buf_ptr, const char* ptr) {
+ auto cp = uint32_t();
+ auto error = 0;
+ auto end = utf8_decode(buf_ptr, &cp, &error);
+ bool result = f(error ? invalid_code_point : cp,
+ string_view(ptr, error ? 1 : to_unsigned(end - buf_ptr)));
+ return result ? (error ? buf_ptr + 1 : end) : nullptr;
+ };
+ auto p = s.data();
+ const size_t block_size = 4; // utf8_decode always reads blocks of 4 chars.
+ if (s.size() >= block_size) {
+ for (auto end = p + s.size() - block_size + 1; p < end;) {
+ p = decode(p, p);
+ if (!p) return;
+ }
+ }
+ if (auto num_chars_left = s.data() + s.size() - p) {
+ char buf[2 * block_size - 1] = {};
+ copy_str<char>(p, p + num_chars_left, buf);
+ const char* buf_ptr = buf;
+ do {
+ auto end = decode(buf_ptr, p);
+ if (!end) return;
+ p += end - buf_ptr;
+ buf_ptr = end;
+ } while (buf_ptr - buf < num_chars_left);
+ }
+}
+
+template <typename Char>
+inline auto compute_width(basic_string_view<Char> s) -> size_t {
+ return s.size();
+}
+
+// Computes approximate display width of a UTF-8 string.
+FMT_CONSTEXPR inline auto compute_width(string_view s) -> size_t {
+ size_t num_code_points = 0;
+ // It is not a lambda for compatibility with C++14.
+ struct count_code_points {
+ size_t* count;
+ FMT_CONSTEXPR auto operator()(uint32_t cp, string_view) const -> bool {
+ *count += detail::to_unsigned(
+ 1 +
+ (cp >= 0x1100 &&
+ (cp <= 0x115f || // Hangul Jamo init. consonants
+ cp == 0x2329 || // LEFT-POINTING ANGLE BRACKET
+ cp == 0x232a || // RIGHT-POINTING ANGLE BRACKET
+ // CJK ... Yi except IDEOGRAPHIC HALF FILL SPACE:
+ (cp >= 0x2e80 && cp <= 0xa4cf && cp != 0x303f) ||
+ (cp >= 0xac00 && cp <= 0xd7a3) || // Hangul Syllables
+ (cp >= 0xf900 && cp <= 0xfaff) || // CJK Compatibility Ideographs
+ (cp >= 0xfe10 && cp <= 0xfe19) || // Vertical Forms
+ (cp >= 0xfe30 && cp <= 0xfe6f) || // CJK Compatibility Forms
+ (cp >= 0xff00 && cp <= 0xff60) || // Fullwidth Forms
+ (cp >= 0xffe0 && cp <= 0xffe6) || // Fullwidth Forms
+ (cp >= 0x20000 && cp <= 0x2fffd) || // CJK
+ (cp >= 0x30000 && cp <= 0x3fffd) ||
+ // Miscellaneous Symbols and Pictographs + Emoticons:
+ (cp >= 0x1f300 && cp <= 0x1f64f) ||
+ // Supplemental Symbols and Pictographs:
+ (cp >= 0x1f900 && cp <= 0x1f9ff))));
+ return true;
+ }
+ };
+ // We could avoid branches by using utf8_decode directly.
+ for_each_codepoint(s, count_code_points{&num_code_points});
+ return num_code_points;
+}
+
+inline auto compute_width(basic_string_view<char8_type> s) -> size_t {
+ return compute_width(
+ string_view(reinterpret_cast<const char*>(s.data()), s.size()));
+}
+
+template <typename Char>
+inline auto code_point_index(basic_string_view<Char> s, size_t n) -> size_t {
+ size_t size = s.size();
+ return n < size ? n : size;
+}
+
+// Calculates the index of the nth code point in a UTF-8 string.
+inline auto code_point_index(string_view s, size_t n) -> size_t {
+ size_t result = s.size();
+ const char* begin = s.begin();
+ for_each_codepoint(s, [begin, &n, &result](uint32_t, string_view sv) {
+ if (n != 0) {
+ --n;
+ return true;
+ }
+ result = to_unsigned(sv.begin() - begin);
+ return false;
+ });
+ return result;
+}
+
+inline auto code_point_index(basic_string_view<char8_type> s, size_t n)
+ -> size_t {
+ return code_point_index(
+ string_view(reinterpret_cast<const char*>(s.data()), s.size()), n);
+}
+
+template <typename T> struct is_integral : std::is_integral<T> {};
+template <> struct is_integral<int128_opt> : std::true_type {};
+template <> struct is_integral<uint128_t> : std::true_type {};
+
+template <typename T>
+using is_signed =
+ std::integral_constant<bool, std::numeric_limits<T>::is_signed ||
+ std::is_same<T, int128_opt>::value>;
+
+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>;
+
+#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
+
+#ifndef FMT_USE_FLOAT128
+# ifdef __clang__
+// Clang emulates GCC, so it has to appear early.
+# if FMT_HAS_INCLUDE(<quadmath.h>)
+# define FMT_USE_FLOAT128 1
+# endif
+# elif defined(__GNUC__)
+// GNU C++:
+# if defined(_GLIBCXX_USE_FLOAT128) && !defined(__STRICT_ANSI__)
+# define FMT_USE_FLOAT128 1
+# endif
+# endif
+# ifndef FMT_USE_FLOAT128
+# define FMT_USE_FLOAT128 0
+# endif
+#endif
+
+#if FMT_USE_FLOAT128
+using float128 = __float128;
+#else
+using float128 = void;
+#endif
+template <typename T> using is_float128 = std::is_same<T, float128>;
+
+template <typename T>
+using is_floating_point =
+ bool_constant<std::is_floating_point<T>::value || is_float128<T>::value>;
+
+template <typename T, bool = std::is_floating_point<T>::value>
+struct is_fast_float : bool_constant<std::numeric_limits<T>::is_iec559 &&
+ sizeof(T) <= sizeof(double)> {};
+template <typename T> struct is_fast_float<T, false> : std::false_type {};
+
+template <typename T>
+using is_double_double = bool_constant<std::numeric_limits<T>::digits == 106>;
+
+#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) {
+ while (begin != end) {
+ 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, ptr_ + size_);
+ size_ += count;
+ begin += count;
+ }
+}
+
+template <typename T, typename Enable = void>
+struct is_locale : std::false_type {};
+template <typename T>
+struct is_locale<T, void_t<decltype(T::classic())>> : std::true_type {};
+} // namespace detail
+
+FMT_BEGIN_EXPORT
+
+// 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 the ``memory_buffer`` type alias for ``char`` instead.
+
+ **Example**::
+
+ auto out = fmt::memory_buffer();
+ fmt::format_to(std::back_inserter(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 to avoid generating type_info for it.
+ FMT_NO_UNIQUE_ADDRESS Allocator alloc_;
+
+ // Deallocate memory allocated by the buffer.
+ FMT_CONSTEXPR20 void deallocate() {
+ T* data = this->data();
+ if (data != store_) alloc_.deallocate(data, this->capacity());
+ }
+
+ protected:
+ FMT_CONSTEXPR20 void grow(size_t size) override {
+ detail::abort_fuzzing_if(size > 5000);
+ const size_t max_size = std::allocator_traits<Allocator>::max_size(alloc_);
+ size_t old_capacity = this->capacity();
+ size_t new_capacity = old_capacity + old_capacity / 2;
+ if (size > new_capacity)
+ new_capacity = size;
+ else if (new_capacity > max_size)
+ new_capacity = size > max_size ? size : max_size;
+ T* old_data = this->data();
+ T* new_data =
+ std::allocator_traits<Allocator>::allocate(alloc_, new_capacity);
+ // Suppress a bogus -Wstringop-overflow in gcc 13.1 (#3481).
+ detail::assume(this->size() <= new_capacity);
+ // The following code doesn't throw, so the raw pointer above doesn't leak.
+ std::uninitialized_copy_n(old_data, this->size(), new_data);
+ 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);
+ }
+
+ public:
+ using value_type = T;
+ using const_reference = const T&;
+
+ FMT_CONSTEXPR20 explicit basic_memory_buffer(
+ const Allocator& alloc = Allocator())
+ : alloc_(alloc) {
+ this->set(store_, SIZE);
+ if (detail::is_constant_evaluated()) detail::fill_n(store_, SIZE, T());
+ }
+ FMT_CONSTEXPR20 ~basic_memory_buffer() { deallocate(); }
+
+ private:
+ // Move data from other to this buffer.
+ FMT_CONSTEXPR20 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);
+ detail::copy_str<T>(other.store_, other.store_ + size, store_);
+ } else {
+ this->set(data, capacity);
+ // Set pointer to the inline array so that delete is not called
+ // when deallocating.
+ other.set(other.store_, 0);
+ other.clear();
+ }
+ this->resize(size);
+ }
+
+ public:
+ /**
+ \rst
+ Constructs a :class:`fmt::basic_memory_buffer` object moving the content
+ of the other object to it.
+ \endrst
+ */
+ FMT_CONSTEXPR20 basic_memory_buffer(basic_memory_buffer&& other) noexcept {
+ move(other);
+ }
+
+ /**
+ \rst
+ Moves the content of the other ``basic_memory_buffer`` object to this one.
+ \endrst
+ */
+ auto operator=(basic_memory_buffer&& other) noexcept -> basic_memory_buffer& {
+ FMT_ASSERT(this != &other, "");
+ deallocate();
+ move(other);
+ return *this;
+ }
+
+ // Returns a copy of the allocator associated with this buffer.
+ auto get_allocator() const -> Allocator { return alloc_; }
+
+ /**
+ Resizes the buffer to contain *count* elements. If T is a POD type new
+ elements may not be initialized.
+ */
+ FMT_CONSTEXPR20 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); }
+
+ using detail::buffer<T>::append;
+ template <typename ContiguousRange>
+ void append(const ContiguousRange& range) {
+ append(range.data(), range.data() + range.size());
+ }
+};
+
+using memory_buffer = basic_memory_buffer<char>;
+
+template <typename T, size_t SIZE, typename Allocator>
+struct is_contiguous<basic_memory_buffer<T, SIZE, Allocator>> : std::true_type {
+};
+
+FMT_END_EXPORT
+namespace detail {
+FMT_API auto write_console(int fd, string_view text) -> bool;
+FMT_API auto write_console(std::FILE* f, string_view text) -> bool;
+FMT_API void print(std::FILE*, string_view);
+} // namespace detail
+
+FMT_BEGIN_EXPORT
+
+// Suppress a misleading warning in older versions of clang.
+#if FMT_CLANG_VERSION
+# pragma clang diagnostic ignored "-Wweak-vtables"
+#endif
+
+/** An error reported from a formatting function. */
+class FMT_SO_VISIBILITY("default") format_error : public std::runtime_error {
+ public:
+ using std::runtime_error::runtime_error;
+};
+
+namespace detail_exported {
+#if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <typename Char, size_t N> struct fixed_string {
+ constexpr fixed_string(const Char (&str)[N]) {
+ detail::copy_str<Char, const Char*, Char*>(static_cast<const Char*>(str),
+ str + N, data);
+ }
+ Char data[N] = {};
+};
+#endif
+
+// Converts a compile-time string to basic_string_view.
+template <typename Char, size_t N>
+constexpr auto compile_string_to_view(const Char (&s)[N])
+ -> basic_string_view<Char> {
+ // Remove trailing NUL character if needed. Won't be present if this is used
+ // with a 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)};
+}
+template <typename Char>
+constexpr auto compile_string_to_view(detail::std_string_view<Char> s)
+ -> basic_string_view<Char> {
+ return {s.data(), s.size()};
+}
+} // namespace detail_exported
+
+class loc_value {
+ private:
+ basic_format_arg<format_context> value_;
+
+ public:
+ template <typename T, FMT_ENABLE_IF(!detail::is_float128<T>::value)>
+ loc_value(T value) : value_(detail::make_arg<format_context>(value)) {}
+
+ template <typename T, FMT_ENABLE_IF(detail::is_float128<T>::value)>
+ loc_value(T) {}
+
+ template <typename Visitor> auto visit(Visitor&& vis) -> decltype(vis(0)) {
+ return visit_format_arg(vis, value_);
+ }
+};
+
+// A locale facet that formats values in UTF-8.
+// It is parameterized on the locale to avoid the heavy <locale> include.
+template <typename Locale> class format_facet : public Locale::facet {
+ private:
+ std::string separator_;
+ std::string grouping_;
+ std::string decimal_point_;
+
+ protected:
+ virtual auto do_put(appender out, loc_value val,
+ const format_specs<>& specs) const -> bool;
+
+ public:
+ static FMT_API typename Locale::id id;
+
+ explicit format_facet(Locale& loc);
+ explicit format_facet(string_view sep = "",
+ std::initializer_list<unsigned char> g = {3},
+ std::string decimal_point = ".")
+ : separator_(sep.data(), sep.size()),
+ grouping_(g.begin(), g.end()),
+ decimal_point_(decimal_point) {}
+
+ auto put(appender out, loc_value val, const format_specs<>& specs) const
+ -> bool {
+ return do_put(out, val, specs);
+ }
+};
+
+namespace detail {
+
+// 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)>
+constexpr auto is_negative(T value) -> bool {
+ return value < 0;
+}
+template <typename T, FMT_ENABLE_IF(!is_signed<T>::value)>
+constexpr auto is_negative(T) -> bool {
+ return false;
+}
+
+template <typename T>
+FMT_CONSTEXPR auto is_supported_floating_point(T) -> bool {
+ if (std::is_same<T, float>()) return FMT_USE_FLOAT;
+ if (std::is_same<T, double>()) return FMT_USE_DOUBLE;
+ if (std::is_same<T, long double>()) return FMT_USE_LONG_DOUBLE;
+ return true;
+}
+
+// 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>>;
+template <typename T>
+using uint64_or_128_t = conditional_t<num_bits<T>() <= 64, uint64_t, uint128_t>;
+
+#define FMT_POWERS_OF_10(factor) \
+ factor * 10, (factor) * 100, (factor) * 1000, (factor) * 10000, \
+ (factor) * 100000, (factor) * 1000000, (factor) * 10000000, \
+ (factor) * 100000000, (factor) * 1000000000
+
+// Converts value in the range [0, 100) to a string.
+constexpr auto digits2(size_t value) -> const char* {
+ // GCC generates slightly better code when value is pointer-size.
+ return &"0001020304050607080910111213141516171819"
+ "2021222324252627282930313233343536373839"
+ "4041424344454647484950515253545556575859"
+ "6061626364656667686970717273747576777879"
+ "8081828384858687888990919293949596979899"[value * 2];
+}
+
+// Sign is a template parameter to workaround a bug in gcc 4.8.
+template <typename Char, typename Sign> constexpr auto sign(Sign s) -> Char {
+#if !FMT_GCC_VERSION || FMT_GCC_VERSION >= 604
+ static_assert(std::is_same<Sign, sign_t>::value, "");
+#endif
+ return static_cast<Char>("\0-+ "[s]);
+}
+
+template <typename T> FMT_CONSTEXPR auto count_digits_fallback(T n) -> int {
+ 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;
+ }
+}
+#if FMT_USE_INT128
+FMT_CONSTEXPR inline auto count_digits(uint128_opt n) -> int {
+ return count_digits_fallback(n);
+}
+#endif
+
+#ifdef FMT_BUILTIN_CLZLL
+// It is a separate function rather than a part of count_digits to workaround
+// the lack of static constexpr in constexpr functions.
+inline auto do_count_digits(uint64_t n) -> int {
+ // This has comparable performance to the version by Kendall Willets
+ // (https://github.com/fmtlib/format-benchmark/blob/master/digits10)
+ // but uses smaller tables.
+ // Maps bsr(n) to ceil(log10(pow(2, bsr(n) + 1) - 1)).
+ static constexpr uint8_t bsr2log10[] = {
+ 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};
+ auto t = bsr2log10[FMT_BUILTIN_CLZLL(n | 1) ^ 63];
+ static constexpr const uint64_t zero_or_powers_of_10[] = {
+ 0, 0, FMT_POWERS_OF_10(1U), FMT_POWERS_OF_10(1000000000ULL),
+ 10000000000000000000ULL};
+ return t - (n < zero_or_powers_of_10[t]);
+}
+#endif
+
+// Returns the number of decimal digits in n. Leading zeros are not counted
+// except for n == 0 in which case count_digits returns 1.
+FMT_CONSTEXPR20 inline auto count_digits(uint64_t n) -> int {
+#ifdef FMT_BUILTIN_CLZLL
+ if (!is_constant_evaluated()) {
+ return do_count_digits(n);
+ }
+#endif
+ return count_digits_fallback(n);
+}
+
+// Counts the number of digits in n. BITS = log2(radix).
+template <int BITS, typename UInt>
+FMT_CONSTEXPR auto count_digits(UInt n) -> int {
+#ifdef FMT_BUILTIN_CLZ
+ if (!is_constant_evaluated() && num_bits<UInt>() == 32)
+ return (FMT_BUILTIN_CLZ(static_cast<uint32_t>(n) | 1) ^ 31) / BITS + 1;
+#endif
+ // Lambda avoids unreachable code warnings from NVHPC.
+ return [](UInt m) {
+ int num_digits = 0;
+ do {
+ ++num_digits;
+ } while ((m >>= BITS) != 0);
+ return num_digits;
+ }(n);
+}
+
+#ifdef FMT_BUILTIN_CLZ
+// It is a separate function rather than a part of count_digits to workaround
+// the lack of static constexpr in constexpr functions.
+FMT_INLINE auto do_count_digits(uint32_t n) -> int {
+// An optimization by Kendall Willets from https://bit.ly/3uOIQrB.
+// This increments the upper 32 bits (log10(T) - 1) when >= T is added.
+# define FMT_INC(T) (((sizeof(#T) - 1ull) << 32) - T)
+ static constexpr uint64_t table[] = {
+ FMT_INC(0), FMT_INC(0), FMT_INC(0), // 8
+ FMT_INC(10), FMT_INC(10), FMT_INC(10), // 64
+ FMT_INC(100), FMT_INC(100), FMT_INC(100), // 512
+ FMT_INC(1000), FMT_INC(1000), FMT_INC(1000), // 4096
+ FMT_INC(10000), FMT_INC(10000), FMT_INC(10000), // 32k
+ FMT_INC(100000), FMT_INC(100000), FMT_INC(100000), // 256k
+ FMT_INC(1000000), FMT_INC(1000000), FMT_INC(1000000), // 2048k
+ FMT_INC(10000000), FMT_INC(10000000), FMT_INC(10000000), // 16M
+ FMT_INC(100000000), FMT_INC(100000000), FMT_INC(100000000), // 128M
+ FMT_INC(1000000000), FMT_INC(1000000000), FMT_INC(1000000000), // 1024M
+ FMT_INC(1000000000), FMT_INC(1000000000) // 4B
+ };
+ auto inc = table[FMT_BUILTIN_CLZ(n | 1) ^ 31];
+ return static_cast<int>((n + inc) >> 32);
+}
+#endif
+
+// Optional version of count_digits for better performance on 32-bit platforms.
+FMT_CONSTEXPR20 inline auto count_digits(uint32_t n) -> int {
+#ifdef FMT_BUILTIN_CLZ
+ if (!is_constant_evaluated()) {
+ return do_count_digits(n);
+ }
+#endif
+ return count_digits_fallback(n);
+}
+
+template <typename Int> constexpr auto digits10() noexcept -> int {
+ return std::numeric_limits<Int>::digits10;
+}
+template <> constexpr auto digits10<int128_opt>() noexcept -> int { return 38; }
+template <> constexpr auto digits10<uint128_t>() noexcept -> int { return 38; }
+
+template <typename Char> struct thousands_sep_result {
+ std::string grouping;
+ Char thousands_sep;
+};
+
+template <typename Char>
+FMT_API auto thousands_sep_impl(locale_ref loc) -> thousands_sep_result<Char>;
+template <typename Char>
+inline auto thousands_sep(locale_ref loc) -> thousands_sep_result<Char> {
+ auto result = thousands_sep_impl<char>(loc);
+ return {result.grouping, Char(result.thousands_sep)};
+}
+template <>
+inline auto thousands_sep(locale_ref loc) -> thousands_sep_result<wchar_t> {
+ return thousands_sep_impl<wchar_t>(loc);
+}
+
+template <typename Char>
+FMT_API auto decimal_point_impl(locale_ref loc) -> Char;
+template <typename Char> inline auto decimal_point(locale_ref loc) -> Char {
+ return Char(decimal_point_impl<char>(loc));
+}
+template <> inline auto decimal_point(locale_ref loc) -> wchar_t {
+ return decimal_point_impl<wchar_t>(loc);
+}
+
+// Compares two characters for equality.
+template <typename Char> auto equal2(const Char* lhs, const char* rhs) -> bool {
+ return lhs[0] == Char(rhs[0]) && lhs[1] == Char(rhs[1]);
+}
+inline auto equal2(const char* lhs, const char* rhs) -> bool {
+ return memcmp(lhs, rhs, 2) == 0;
+}
+
+// Copies two characters from src to dst.
+template <typename Char>
+FMT_CONSTEXPR20 FMT_INLINE void copy2(Char* dst, const char* src) {
+ if (!is_constant_evaluated() && sizeof(Char) == sizeof(char)) {
+ memcpy(dst, src, 2);
+ return;
+ }
+ *dst++ = static_cast<Char>(*src++);
+ *dst = static_cast<Char>(*src);
+}
+
+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>
+FMT_CONSTEXPR20 auto format_decimal(Char* out, UInt value, int size)
+ -> format_decimal_result<Char*> {
+ 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, digits2(static_cast<size_t>(value % 100)));
+ value /= 100;
+ }
+ if (value < 10) {
+ *--out = static_cast<Char>('0' + value);
+ return {out, end};
+ }
+ out -= 2;
+ copy2(out, digits2(static_cast<size_t>(value)));
+ return {out, end};
+}
+
+template <typename Char, typename UInt, typename Iterator,
+ FMT_ENABLE_IF(!std::is_pointer<remove_cvref_t<Iterator>>::value)>
+FMT_CONSTEXPR inline auto format_decimal(Iterator out, UInt value, int size)
+ -> format_decimal_result<Iterator> {
+ // 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_noinline<Char>(buffer, end, out)};
+}
+
+template <unsigned BASE_BITS, typename Char, typename UInt>
+FMT_CONSTEXPR auto format_uint(Char* buffer, UInt value, int num_digits,
+ bool upper = false) -> Char* {
+ buffer += num_digits;
+ Char* end = buffer;
+ do {
+ const char* digits = upper ? "0123456789ABCDEF" : "0123456789abcdef";
+ unsigned digit = static_cast<unsigned>(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, typename It, typename UInt>
+FMT_CONSTEXPR inline auto format_uint(It out, UInt value, int num_digits,
+ bool upper = false) -> It {
+ 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_noinline<Char>(buffer, buffer + num_digits, out);
+}
+
+// A converter from UTF-8 to UTF-16.
+class utf8_to_utf16 {
+ private:
+ basic_memory_buffer<wchar_t> buffer_;
+
+ public:
+ FMT_API explicit utf8_to_utf16(string_view s);
+ operator basic_string_view<wchar_t>() const { return {&buffer_[0], size()}; }
+ auto size() const -> size_t { return buffer_.size() - 1; }
+ auto c_str() const -> const wchar_t* { return &buffer_[0]; }
+ auto str() const -> std::wstring { return {&buffer_[0], size()}; }
+};
+
+enum class to_utf8_error_policy { abort, replace };
+
+// A converter from UTF-16/UTF-32 (host endian) to UTF-8.
+template <typename WChar, typename Buffer = memory_buffer> class to_utf8 {
+ private:
+ Buffer buffer_;
+
+ public:
+ to_utf8() {}
+ explicit to_utf8(basic_string_view<WChar> s,
+ to_utf8_error_policy policy = to_utf8_error_policy::abort) {
+ static_assert(sizeof(WChar) == 2 || sizeof(WChar) == 4,
+ "Expect utf16 or utf32");
+ if (!convert(s, policy))
+ FMT_THROW(std::runtime_error(sizeof(WChar) == 2 ? "invalid utf16"
+ : "invalid utf32"));
+ }
+ operator string_view() const { return string_view(&buffer_[0], size()); }
+ auto size() const -> size_t { return buffer_.size() - 1; }
+ auto c_str() const -> const char* { return &buffer_[0]; }
+ auto str() const -> std::string { return std::string(&buffer_[0], size()); }
+
+ // Performs conversion returning a bool instead of throwing exception on
+ // conversion error. This method may still throw in case of memory allocation
+ // error.
+ auto convert(basic_string_view<WChar> s,
+ to_utf8_error_policy policy = to_utf8_error_policy::abort)
+ -> bool {
+ if (!convert(buffer_, s, policy)) return false;
+ buffer_.push_back(0);
+ return true;
+ }
+ static auto convert(Buffer& buf, basic_string_view<WChar> s,
+ to_utf8_error_policy policy = to_utf8_error_policy::abort)
+ -> bool {
+ for (auto p = s.begin(); p != s.end(); ++p) {
+ uint32_t c = static_cast<uint32_t>(*p);
+ if (sizeof(WChar) == 2 && c >= 0xd800 && c <= 0xdfff) {
+ // Handle a surrogate pair.
+ ++p;
+ if (p == s.end() || (c & 0xfc00) != 0xd800 || (*p & 0xfc00) != 0xdc00) {
+ if (policy == to_utf8_error_policy::abort) return false;
+ buf.append(string_view("\xEF\xBF\xBD"));
+ --p;
+ } else {
+ c = (c << 10) + static_cast<uint32_t>(*p) - 0x35fdc00;
+ }
+ } else if (c < 0x80) {
+ buf.push_back(static_cast<char>(c));
+ } else if (c < 0x800) {
+ buf.push_back(static_cast<char>(0xc0 | (c >> 6)));
+ buf.push_back(static_cast<char>(0x80 | (c & 0x3f)));
+ } else if ((c >= 0x800 && c <= 0xd7ff) || (c >= 0xe000 && c <= 0xffff)) {
+ buf.push_back(static_cast<char>(0xe0 | (c >> 12)));
+ buf.push_back(static_cast<char>(0x80 | ((c & 0xfff) >> 6)));
+ buf.push_back(static_cast<char>(0x80 | (c & 0x3f)));
+ } else if (c >= 0x10000 && c <= 0x10ffff) {
+ buf.push_back(static_cast<char>(0xf0 | (c >> 18)));
+ buf.push_back(static_cast<char>(0x80 | ((c & 0x3ffff) >> 12)));
+ buf.push_back(static_cast<char>(0x80 | ((c & 0xfff) >> 6)));
+ buf.push_back(static_cast<char>(0x80 | (c & 0x3f)));
+ } else {
+ return false;
+ }
+ }
+ return true;
+ }
+};
+
+// Computes 128-bit result of multiplication of two 64-bit unsigned integers.
+inline auto umul128(uint64_t x, uint64_t y) noexcept -> uint128_fallback {
+#if FMT_USE_INT128
+ auto p = static_cast<uint128_opt>(x) * static_cast<uint128_opt>(y);
+ return {static_cast<uint64_t>(p >> 64), static_cast<uint64_t>(p)};
+#elif defined(_MSC_VER) && defined(_M_X64)
+ auto hi = uint64_t();
+ auto lo = _umul128(x, y, &hi);
+ return {hi, lo};
+#else
+ const uint64_t mask = static_cast<uint64_t>(max_value<uint32_t>());
+
+ uint64_t a = x >> 32;
+ uint64_t b = x & mask;
+ uint64_t c = y >> 32;
+ uint64_t d = y & mask;
+
+ uint64_t ac = a * c;
+ uint64_t bc = b * c;
+ uint64_t ad = a * d;
+ uint64_t bd = b * d;
+
+ uint64_t intermediate = (bd >> 32) + (ad & mask) + (bc & mask);
+
+ return {ac + (intermediate >> 32) + (ad >> 32) + (bc >> 32),
+ (intermediate << 32) + (bd & mask)};
+#endif
+}
+
+namespace dragonbox {
+// Computes floor(log10(pow(2, e))) for e in [-2620, 2620] using the method from
+// https://fmt.dev/papers/Dragonbox.pdf#page=28, section 6.1.
+inline auto floor_log10_pow2(int e) noexcept -> int {
+ FMT_ASSERT(e <= 2620 && e >= -2620, "too large exponent");
+ static_assert((-1 >> 1) == -1, "right shift is not arithmetic");
+ return (e * 315653) >> 20;
+}
+
+inline auto floor_log2_pow10(int e) noexcept -> int {
+ FMT_ASSERT(e <= 1233 && e >= -1233, "too large exponent");
+ return (e * 1741647) >> 19;
+}
+
+// Computes upper 64 bits of multiplication of two 64-bit unsigned integers.
+inline auto umul128_upper64(uint64_t x, uint64_t y) noexcept -> uint64_t {
+#if FMT_USE_INT128
+ auto p = static_cast<uint128_opt>(x) * static_cast<uint128_opt>(y);
+ return static_cast<uint64_t>(p >> 64);
+#elif defined(_MSC_VER) && defined(_M_X64)
+ return __umulh(x, y);
+#else
+ return umul128(x, y).high();
+#endif
+}
+
+// Computes upper 128 bits of multiplication of a 64-bit unsigned integer and a
+// 128-bit unsigned integer.
+inline auto umul192_upper128(uint64_t x, uint128_fallback y) noexcept
+ -> uint128_fallback {
+ uint128_fallback r = umul128(x, y.high());
+ r += umul128_upper64(x, y.low());
+ return r;
+}
+
+FMT_API auto get_cached_power(int k) noexcept -> uint128_fallback;
+
+// Type-specific information that Dragonbox uses.
+template <typename T, typename Enable = void> struct float_info;
+
+template <> struct float_info<float> {
+ using carrier_uint = uint32_t;
+ static const int exponent_bits = 8;
+ 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 shorter_interval_tie_lower_threshold = -35;
+ static const int shorter_interval_tie_upper_threshold = -35;
+};
+
+template <> struct float_info<double> {
+ using carrier_uint = uint64_t;
+ static const int exponent_bits = 11;
+ 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 = 341;
+ static const int shorter_interval_tie_lower_threshold = -77;
+ static const int shorter_interval_tie_upper_threshold = -77;
+};
+
+// An 80- or 128-bit floating point number.
+template <typename T>
+struct float_info<T, enable_if_t<std::numeric_limits<T>::digits == 64 ||
+ std::numeric_limits<T>::digits == 113 ||
+ is_float128<T>::value>> {
+ using carrier_uint = detail::uint128_t;
+ static const int exponent_bits = 15;
+};
+
+// A double-double floating point number.
+template <typename T>
+struct float_info<T, enable_if_t<is_double_double<T>::value>> {
+ using carrier_uint = detail::uint128_t;
+};
+
+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 auto to_decimal(T x) noexcept -> decimal_fp<T>;
+} // namespace dragonbox
+
+// Returns true iff Float has the implicit bit which is not stored.
+template <typename Float> constexpr auto has_implicit_bit() -> bool {
+ // An 80-bit FP number has a 64-bit significand an no implicit bit.
+ return std::numeric_limits<Float>::digits != 64;
+}
+
+// Returns the number of significand bits stored in Float. The implicit bit is
+// not counted since it is not stored.
+template <typename Float> constexpr auto num_significand_bits() -> int {
+ // std::numeric_limits may not support __float128.
+ return is_float128<Float>() ? 112
+ : (std::numeric_limits<Float>::digits -
+ (has_implicit_bit<Float>() ? 1 : 0));
+}
+
+template <typename Float>
+constexpr auto exponent_mask() ->
+ typename dragonbox::float_info<Float>::carrier_uint {
+ using float_uint = typename dragonbox::float_info<Float>::carrier_uint;
+ return ((float_uint(1) << dragonbox::float_info<Float>::exponent_bits) - 1)
+ << num_significand_bits<Float>();
+}
+template <typename Float> constexpr auto exponent_bias() -> int {
+ // std::numeric_limits may not support __float128.
+ return is_float128<Float>() ? 16383
+ : std::numeric_limits<Float>::max_exponent - 1;
+}
+
+// Writes the exponent exp in the form "[+-]d{2,3}" to buffer.
+template <typename Char, typename It>
+FMT_CONSTEXPR auto write_exponent(int exp, It 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 = digits2(to_unsigned(exp / 100));
+ if (exp >= 1000) *it++ = static_cast<Char>(top[0]);
+ *it++ = static_cast<Char>(top[1]);
+ exp %= 100;
+ }
+ const char* d = digits2(to_unsigned(exp));
+ *it++ = static_cast<Char>(d[0]);
+ *it++ = static_cast<Char>(d[1]);
+ return it;
+}
+
+// A floating-point number f * pow(2, e) where F is an unsigned type.
+template <typename F> struct basic_fp {
+ F f;
+ int e;
+
+ static constexpr const int num_significand_bits =
+ static_cast<int>(sizeof(F) * num_bits<unsigned char>());
+
+ constexpr basic_fp() : f(0), e(0) {}
+ constexpr basic_fp(uint64_t f_val, int e_val) : f(f_val), e(e_val) {}
+
+ // Constructs fp from an IEEE754 floating-point number.
+ template <typename Float> FMT_CONSTEXPR basic_fp(Float n) { assign(n); }
+
+ // Assigns n to this and return true iff predecessor is closer than successor.
+ template <typename Float, FMT_ENABLE_IF(!is_double_double<Float>::value)>
+ FMT_CONSTEXPR auto assign(Float n) -> bool {
+ static_assert(std::numeric_limits<Float>::digits <= 113, "unsupported FP");
+ // Assume Float is in the format [sign][exponent][significand].
+ using carrier_uint = typename dragonbox::float_info<Float>::carrier_uint;
+ const auto num_float_significand_bits =
+ detail::num_significand_bits<Float>();
+ const auto implicit_bit = carrier_uint(1) << num_float_significand_bits;
+ const auto significand_mask = implicit_bit - 1;
+ auto u = bit_cast<carrier_uint>(n);
+ f = static_cast<F>(u & significand_mask);
+ auto biased_e = static_cast<int>((u & exponent_mask<Float>()) >>
+ num_float_significand_bits);
+ // The predecessor is closer if n is a normalized power of 2 (f == 0)
+ // other than the smallest normalized number (biased_e > 1).
+ auto is_predecessor_closer = f == 0 && biased_e > 1;
+ if (biased_e == 0)
+ biased_e = 1; // Subnormals use biased exponent 1 (min exponent).
+ else if (has_implicit_bit<Float>())
+ f += static_cast<F>(implicit_bit);
+ e = biased_e - exponent_bias<Float>() - num_float_significand_bits;
+ if (!has_implicit_bit<Float>()) ++e;
+ return is_predecessor_closer;
+ }
+
+ template <typename Float, FMT_ENABLE_IF(is_double_double<Float>::value)>
+ FMT_CONSTEXPR auto assign(Float n) -> bool {
+ static_assert(std::numeric_limits<double>::is_iec559, "unsupported FP");
+ return assign(static_cast<double>(n));
+ }
+};
+
+using fp = basic_fp<unsigned long long>;
+
+// Normalizes the value converted from double and multiplied by (1 << SHIFT).
+template <int SHIFT = 0, typename F>
+FMT_CONSTEXPR auto normalize(basic_fp<F> value) -> basic_fp<F> {
+ // Handle subnormals.
+ const auto implicit_bit = F(1) << num_significand_bits<double>();
+ const auto shifted_implicit_bit = implicit_bit << SHIFT;
+ while ((value.f & shifted_implicit_bit) == 0) {
+ value.f <<= 1;
+ --value.e;
+ }
+ // Subtract 1 to account for hidden bit.
+ const auto offset = basic_fp<F>::num_significand_bits -
+ num_significand_bits<double>() - SHIFT - 1;
+ value.f <<= offset;
+ value.e -= offset;
+ return value;
+}
+
+// Computes lhs * rhs / pow(2, 64) rounded to nearest with half-up tie breaking.
+FMT_CONSTEXPR inline auto multiply(uint64_t lhs, uint64_t rhs) -> uint64_t {
+#if FMT_USE_INT128
+ auto product = static_cast<__uint128_t>(lhs) * rhs;
+ auto f = static_cast<uint64_t>(product >> 64);
+ return (static_cast<uint64_t>(product) & (1ULL << 63)) != 0 ? f + 1 : f;
+#else
+ // Multiply 32-bit parts of significands.
+ uint64_t mask = (1ULL << 32) - 1;
+ uint64_t a = lhs >> 32, b = lhs & mask;
+ uint64_t c = rhs >> 32, d = rhs & mask;
+ uint64_t ac = a * c, bc = b * c, ad = a * d, bd = b * d;
+ // Compute mid 64-bit of result and round.
+ uint64_t mid = (bd >> 32) + (ad & mask) + (bc & mask) + (1U << 31);
+ return ac + (ad >> 32) + (bc >> 32) + (mid >> 32);
+#endif
+}
+
+FMT_CONSTEXPR inline auto operator*(fp x, fp y) -> fp {
+ return {multiply(x.f, y.f), x.e + y.e + 64};
+}
+
+template <typename T, bool doublish = num_bits<T>() == num_bits<double>()>
+using convert_float_result =
+ conditional_t<std::is_same<T, float>::value || doublish, double, T>;
+
+template <typename T>
+constexpr auto convert_float(T value) -> convert_float_result<T> {
+ return static_cast<convert_float_result<T>>(value);
+}
+
+template <typename OutputIt, typename Char>
+FMT_NOINLINE FMT_CONSTEXPR auto fill(OutputIt it, size_t n,
+ const fill_t<Char>& fill) -> OutputIt {
+ auto fill_size = fill.size();
+ if (fill_size == 1) return detail::fill_n(it, n, fill[0]);
+ auto data = fill.data();
+ for (size_t i = 0; i < n; ++i)
+ it = copy_str<Char>(data, 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>
+FMT_CONSTEXPR auto write_padded(OutputIt out, const format_specs<Char>& specs,
+ size_t size, size_t width, F&& f) -> OutputIt {
+ 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;
+ // Shifts are encoded as string literals because static constexpr is not
+ // supported in constexpr functions.
+ auto* shifts = align == align::left ? "\x1f\x1f\x00\x01" : "\x00\x1f\x00\x01";
+ size_t left_padding = padding >> shifts[specs.align];
+ size_t right_padding = padding - left_padding;
+ auto it = reserve(out, size + padding * specs.fill.size());
+ if (left_padding != 0) it = fill(it, left_padding, specs.fill);
+ it = f(it);
+ if (right_padding != 0) it = fill(it, right_padding, specs.fill);
+ return base_iterator(out, it);
+}
+
+template <align::type align = align::left, typename OutputIt, typename Char,
+ typename F>
+constexpr auto write_padded(OutputIt out, const format_specs<Char>& specs,
+ size_t size, F&& f) -> OutputIt {
+ return write_padded<align>(out, specs, size, size, f);
+}
+
+template <align::type align = align::left, typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write_bytes(OutputIt out, string_view bytes,
+ const format_specs<Char>& specs) -> OutputIt {
+ return write_padded<align>(
+ out, specs, bytes.size(), [bytes](reserve_iterator<OutputIt> it) {
+ const char* data = bytes.data();
+ return copy_str<Char>(data, data + bytes.size(), it);
+ });
+}
+
+template <typename Char, typename OutputIt, typename UIntPtr>
+auto write_ptr(OutputIt out, UIntPtr value, const format_specs<Char>* specs)
+ -> OutputIt {
+ int num_digits = count_digits<4>(value);
+ auto size = to_unsigned(num_digits) + size_t(2);
+ auto write = [=](reserve_iterator<OutputIt> 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)));
+}
+
+// Returns true iff the code point cp is printable.
+FMT_API auto is_printable(uint32_t cp) -> bool;
+
+inline auto needs_escape(uint32_t cp) -> bool {
+ return cp < 0x20 || cp == 0x7f || cp == '"' || cp == '\\' ||
+ !is_printable(cp);
+}
+
+template <typename Char> struct find_escape_result {
+ const Char* begin;
+ const Char* end;
+ uint32_t cp;
+};
+
+template <typename Char>
+using make_unsigned_char =
+ typename conditional_t<std::is_integral<Char>::value,
+ std::make_unsigned<Char>,
+ type_identity<uint32_t>>::type;
+
+template <typename Char>
+auto find_escape(const Char* begin, const Char* end)
+ -> find_escape_result<Char> {
+ for (; begin != end; ++begin) {
+ uint32_t cp = static_cast<make_unsigned_char<Char>>(*begin);
+ if (const_check(sizeof(Char) == 1) && cp >= 0x80) continue;
+ if (needs_escape(cp)) return {begin, begin + 1, cp};
+ }
+ return {begin, nullptr, 0};
+}
+
+inline auto find_escape(const char* begin, const char* end)
+ -> find_escape_result<char> {
+ if (!is_utf8()) return find_escape<char>(begin, end);
+ auto result = find_escape_result<char>{end, nullptr, 0};
+ for_each_codepoint(string_view(begin, to_unsigned(end - begin)),
+ [&](uint32_t cp, string_view sv) {
+ if (needs_escape(cp)) {
+ result = {sv.begin(), sv.end(), cp};
+ return false;
+ }
+ return true;
+ });
+ return result;
+}
+
+#define FMT_STRING_IMPL(s, base, explicit) \
+ [] { \
+ /* Use the hidden visibility as a workaround for a GCC bug (#1973). */ \
+ /* Use a macro-like name to avoid shadowing warnings. */ \
+ struct FMT_VISIBILITY("hidden") FMT_COMPILE_STRING : base { \
+ using char_type FMT_MAYBE_UNUSED = fmt::remove_cvref_t<decltype(s[0])>; \
+ FMT_MAYBE_UNUSED FMT_CONSTEXPR explicit \
+ operator fmt::basic_string_view<char_type>() const { \
+ return fmt::detail_exported::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::detail::compile_string, )
+
+template <size_t width, typename Char, typename OutputIt>
+auto write_codepoint(OutputIt out, char prefix, uint32_t cp) -> OutputIt {
+ *out++ = static_cast<Char>('\\');
+ *out++ = static_cast<Char>(prefix);
+ Char buf[width];
+ fill_n(buf, width, static_cast<Char>('0'));
+ format_uint<4>(buf, cp, width);
+ return copy_str<Char>(buf, buf + width, out);
+}
+
+template <typename OutputIt, typename Char>
+auto write_escaped_cp(OutputIt out, const find_escape_result<Char>& escape)
+ -> OutputIt {
+ auto c = static_cast<Char>(escape.cp);
+ switch (escape.cp) {
+ case '\n':
+ *out++ = static_cast<Char>('\\');
+ c = static_cast<Char>('n');
+ break;
+ case '\r':
+ *out++ = static_cast<Char>('\\');
+ c = static_cast<Char>('r');
+ break;
+ case '\t':
+ *out++ = static_cast<Char>('\\');
+ c = static_cast<Char>('t');
+ break;
+ case '"':
+ FMT_FALLTHROUGH;
+ case '\'':
+ FMT_FALLTHROUGH;
+ case '\\':
+ *out++ = static_cast<Char>('\\');
+ break;
+ default:
+ if (escape.cp < 0x100) {
+ return write_codepoint<2, Char>(out, 'x', escape.cp);
+ }
+ if (escape.cp < 0x10000) {
+ return write_codepoint<4, Char>(out, 'u', escape.cp);
+ }
+ if (escape.cp < 0x110000) {
+ return write_codepoint<8, Char>(out, 'U', escape.cp);
+ }
+ for (Char escape_char : basic_string_view<Char>(
+ escape.begin, to_unsigned(escape.end - escape.begin))) {
+ out = write_codepoint<2, Char>(out, 'x',
+ static_cast<uint32_t>(escape_char) & 0xFF);
+ }
+ return out;
+ }
+ *out++ = c;
+ return out;
+}
+
+template <typename Char, typename OutputIt>
+auto write_escaped_string(OutputIt out, basic_string_view<Char> str)
+ -> OutputIt {
+ *out++ = static_cast<Char>('"');
+ auto begin = str.begin(), end = str.end();
+ do {
+ auto escape = find_escape(begin, end);
+ out = copy_str<Char>(begin, escape.begin, out);
+ begin = escape.end;
+ if (!begin) break;
+ out = write_escaped_cp<OutputIt, Char>(out, escape);
+ } while (begin != end);
+ *out++ = static_cast<Char>('"');
+ return out;
+}
+
+template <typename Char, typename OutputIt>
+auto write_escaped_char(OutputIt out, Char v) -> OutputIt {
+ Char v_array[1] = {v};
+ *out++ = static_cast<Char>('\'');
+ if ((needs_escape(static_cast<uint32_t>(v)) && v != static_cast<Char>('"')) ||
+ v == static_cast<Char>('\'')) {
+ out = write_escaped_cp(out,
+ find_escape_result<Char>{v_array, v_array + 1,
+ static_cast<uint32_t>(v)});
+ } else {
+ *out++ = v;
+ }
+ *out++ = static_cast<Char>('\'');
+ return out;
+}
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write_char(OutputIt out, Char value,
+ const format_specs<Char>& specs) -> OutputIt {
+ bool is_debug = specs.type == presentation_type::debug;
+ return write_padded(out, specs, 1, [=](reserve_iterator<OutputIt> it) {
+ if (is_debug) return write_escaped_char(it, value);
+ *it++ = value;
+ return it;
+ });
+}
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out, Char value,
+ const format_specs<Char>& specs, locale_ref loc = {})
+ -> OutputIt {
+ // char is formatted as unsigned char for consistency across platforms.
+ using unsigned_type =
+ conditional_t<std::is_same<Char, char>::value, unsigned char, unsigned>;
+ return check_char_specs(specs)
+ ? write_char(out, value, specs)
+ : write(out, static_cast<unsigned_type>(value), specs, loc);
+}
+
+// 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;
+
+ FMT_CONSTEXPR write_int_data(int num_digits, unsigned prefix,
+ const format_specs<Char>& specs)
+ : size((prefix >> 24) + 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 >> 24) + 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 write_digits(it).
+// prefix contains chars in three lower bytes and the size in the fourth byte.
+template <typename OutputIt, typename Char, typename W>
+FMT_CONSTEXPR FMT_INLINE auto write_int(OutputIt out, int num_digits,
+ unsigned prefix,
+ const format_specs<Char>& specs,
+ W write_digits) -> OutputIt {
+ // Slightly faster check for specs.width == 0 && specs.precision == -1.
+ if ((specs.width | (specs.precision + 1)) == 0) {
+ auto it = reserve(out, to_unsigned(num_digits) + (prefix >> 24));
+ if (prefix != 0) {
+ for (unsigned p = prefix & 0xffffff; p != 0; p >>= 8)
+ *it++ = static_cast<Char>(p & 0xff);
+ }
+ return base_iterator(out, write_digits(it));
+ }
+ auto data = write_int_data<Char>(num_digits, prefix, specs);
+ return write_padded<align::right>(
+ out, specs, data.size, [=](reserve_iterator<OutputIt> it) {
+ for (unsigned p = prefix & 0xffffff; p != 0; p >>= 8)
+ *it++ = static_cast<Char>(p & 0xff);
+ it = detail::fill_n(it, data.padding, static_cast<Char>('0'));
+ return write_digits(it);
+ });
+}
+
+template <typename Char> class digit_grouping {
+ private:
+ std::string grouping_;
+ std::basic_string<Char> thousands_sep_;
+
+ struct next_state {
+ std::string::const_iterator group;
+ int pos;
+ };
+ auto initial_state() const -> next_state { return {grouping_.begin(), 0}; }
+
+ // Returns the next digit group separator position.
+ auto next(next_state& state) const -> int {
+ if (thousands_sep_.empty()) return max_value<int>();
+ if (state.group == grouping_.end()) return state.pos += grouping_.back();
+ if (*state.group <= 0 || *state.group == max_value<char>())
+ return max_value<int>();
+ state.pos += *state.group++;
+ return state.pos;
+ }
+
+ public:
+ explicit digit_grouping(locale_ref loc, bool localized = true) {
+ if (!localized) return;
+ auto sep = thousands_sep<Char>(loc);
+ grouping_ = sep.grouping;
+ if (sep.thousands_sep) thousands_sep_.assign(1, sep.thousands_sep);
+ }
+ digit_grouping(std::string grouping, std::basic_string<Char> sep)
+ : grouping_(std::move(grouping)), thousands_sep_(std::move(sep)) {}
+
+ auto has_separator() const -> bool { return !thousands_sep_.empty(); }
+
+ auto count_separators(int num_digits) const -> int {
+ int count = 0;
+ auto state = initial_state();
+ while (num_digits > next(state)) ++count;
+ return count;
+ }
+
+ // Applies grouping to digits and write the output to out.
+ template <typename Out, typename C>
+ auto apply(Out out, basic_string_view<C> digits) const -> Out {
+ auto num_digits = static_cast<int>(digits.size());
+ auto separators = basic_memory_buffer<int>();
+ separators.push_back(0);
+ auto state = initial_state();
+ while (int i = next(state)) {
+ if (i >= num_digits) break;
+ separators.push_back(i);
+ }
+ for (int i = 0, sep_index = static_cast<int>(separators.size() - 1);
+ i < num_digits; ++i) {
+ if (num_digits - i == separators[sep_index]) {
+ out =
+ copy_str<Char>(thousands_sep_.data(),
+ thousands_sep_.data() + thousands_sep_.size(), out);
+ --sep_index;
+ }
+ *out++ = static_cast<Char>(digits[to_unsigned(i)]);
+ }
+ return out;
+ }
+};
+
+FMT_CONSTEXPR inline void prefix_append(unsigned& prefix, unsigned value) {
+ prefix |= prefix != 0 ? value << 8 : value;
+ prefix += (1u + (value > 0xff ? 1 : 0)) << 24;
+}
+
+// Writes a decimal integer with digit grouping.
+template <typename OutputIt, typename UInt, typename Char>
+auto write_int(OutputIt out, UInt value, unsigned prefix,
+ const format_specs<Char>& specs,
+ const digit_grouping<Char>& grouping) -> OutputIt {
+ static_assert(std::is_same<uint64_or_128_t<UInt>, UInt>::value, "");
+ int num_digits = 0;
+ auto buffer = memory_buffer();
+ switch (specs.type) {
+ case presentation_type::none:
+ case presentation_type::dec: {
+ num_digits = count_digits(value);
+ format_decimal<char>(appender(buffer), value, num_digits);
+ break;
+ }
+ case presentation_type::hex_lower:
+ case presentation_type::hex_upper: {
+ bool upper = specs.type == presentation_type::hex_upper;
+ if (specs.alt)
+ prefix_append(prefix, unsigned(upper ? 'X' : 'x') << 8 | '0');
+ num_digits = count_digits<4>(value);
+ format_uint<4, char>(appender(buffer), value, num_digits, upper);
+ break;
+ }
+ case presentation_type::bin_lower:
+ case presentation_type::bin_upper: {
+ bool upper = specs.type == presentation_type::bin_upper;
+ if (specs.alt)
+ prefix_append(prefix, unsigned(upper ? 'B' : 'b') << 8 | '0');
+ num_digits = count_digits<1>(value);
+ format_uint<1, char>(appender(buffer), value, num_digits);
+ break;
+ }
+ case presentation_type::oct: {
+ num_digits = count_digits<3>(value);
+ // Octal prefix '0' is counted as a digit, so only add it if precision
+ // is not greater than the number of digits.
+ if (specs.alt && specs.precision <= num_digits && value != 0)
+ prefix_append(prefix, '0');
+ format_uint<3, char>(appender(buffer), value, num_digits);
+ break;
+ }
+ case presentation_type::chr:
+ return write_char(out, static_cast<Char>(value), specs);
+ default:
+ throw_format_error("invalid format specifier");
+ }
+
+ unsigned size = (prefix != 0 ? prefix >> 24 : 0) + to_unsigned(num_digits) +
+ to_unsigned(grouping.count_separators(num_digits));
+ return write_padded<align::right>(
+ out, specs, size, size, [&](reserve_iterator<OutputIt> it) {
+ for (unsigned p = prefix & 0xffffff; p != 0; p >>= 8)
+ *it++ = static_cast<Char>(p & 0xff);
+ return grouping.apply(it, string_view(buffer.data(), buffer.size()));
+ });
+}
+
+// Writes a localized value.
+FMT_API auto write_loc(appender out, loc_value value,
+ const format_specs<>& specs, locale_ref loc) -> bool;
+template <typename OutputIt, typename Char>
+inline auto write_loc(OutputIt, loc_value, const format_specs<Char>&,
+ locale_ref) -> bool {
+ return false;
+}
+
+template <typename UInt> struct write_int_arg {
+ UInt abs_value;
+ unsigned prefix;
+};
+
+template <typename T>
+FMT_CONSTEXPR auto make_write_int_arg(T value, sign_t sign)
+ -> write_int_arg<uint32_or_64_or_128_t<T>> {
+ auto prefix = 0u;
+ auto abs_value = static_cast<uint32_or_64_or_128_t<T>>(value);
+ if (is_negative(value)) {
+ prefix = 0x01000000 | '-';
+ abs_value = 0 - abs_value;
+ } else {
+ constexpr const unsigned prefixes[4] = {0, 0, 0x1000000u | '+',
+ 0x1000000u | ' '};
+ prefix = prefixes[sign];
+ }
+ return {abs_value, prefix};
+}
+
+template <typename Char = char> struct loc_writer {
+ buffer_appender<Char> out;
+ const format_specs<Char>& specs;
+ std::basic_string<Char> sep;
+ std::string grouping;
+ std::basic_string<Char> decimal_point;
+
+ template <typename T, FMT_ENABLE_IF(is_integer<T>::value)>
+ auto operator()(T value) -> bool {
+ auto arg = make_write_int_arg(value, specs.sign);
+ write_int(out, static_cast<uint64_or_128_t<T>>(arg.abs_value), arg.prefix,
+ specs, digit_grouping<Char>(grouping, sep));
+ return true;
+ }
+
+ template <typename T, FMT_ENABLE_IF(!is_integer<T>::value)>
+ auto operator()(T) -> bool {
+ return false;
+ }
+};
+
+template <typename Char, typename OutputIt, typename T>
+FMT_CONSTEXPR FMT_INLINE auto write_int(OutputIt out, write_int_arg<T> arg,
+ const format_specs<Char>& specs,
+ locale_ref) -> OutputIt {
+ static_assert(std::is_same<T, uint32_or_64_or_128_t<T>>::value, "");
+ auto abs_value = arg.abs_value;
+ auto prefix = arg.prefix;
+ switch (specs.type) {
+ case presentation_type::none:
+ case presentation_type::dec: {
+ auto num_digits = count_digits(abs_value);
+ return write_int(
+ out, num_digits, prefix, specs, [=](reserve_iterator<OutputIt> it) {
+ return format_decimal<Char>(it, abs_value, num_digits).end;
+ });
+ }
+ case presentation_type::hex_lower:
+ case presentation_type::hex_upper: {
+ bool upper = specs.type == presentation_type::hex_upper;
+ if (specs.alt)
+ prefix_append(prefix, unsigned(upper ? 'X' : 'x') << 8 | '0');
+ int num_digits = count_digits<4>(abs_value);
+ return write_int(
+ out, num_digits, prefix, specs, [=](reserve_iterator<OutputIt> it) {
+ return format_uint<4, Char>(it, abs_value, num_digits, upper);
+ });
+ }
+ case presentation_type::bin_lower:
+ case presentation_type::bin_upper: {
+ bool upper = specs.type == presentation_type::bin_upper;
+ if (specs.alt)
+ prefix_append(prefix, unsigned(upper ? 'B' : 'b') << 8 | '0');
+ int num_digits = count_digits<1>(abs_value);
+ return write_int(out, num_digits, prefix, specs,
+ [=](reserve_iterator<OutputIt> it) {
+ return format_uint<1, Char>(it, abs_value, num_digits);
+ });
+ }
+ case presentation_type::oct: {
+ int num_digits = count_digits<3>(abs_value);
+ // Octal prefix '0' is counted as a digit, so only add it if precision
+ // is not greater than the number of digits.
+ if (specs.alt && specs.precision <= num_digits && abs_value != 0)
+ prefix_append(prefix, '0');
+ return write_int(out, num_digits, prefix, specs,
+ [=](reserve_iterator<OutputIt> it) {
+ return format_uint<3, Char>(it, abs_value, num_digits);
+ });
+ }
+ case presentation_type::chr:
+ return write_char(out, static_cast<Char>(abs_value), specs);
+ default:
+ throw_format_error("invalid format specifier");
+ }
+ return out;
+}
+template <typename Char, typename OutputIt, typename T>
+FMT_CONSTEXPR FMT_NOINLINE auto write_int_noinline(
+ OutputIt out, write_int_arg<T> arg, const format_specs<Char>& specs,
+ locale_ref loc) -> OutputIt {
+ return write_int(out, arg, specs, loc);
+}
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_integral<T>::value &&
+ !std::is_same<T, bool>::value &&
+ std::is_same<OutputIt, buffer_appender<Char>>::value)>
+FMT_CONSTEXPR FMT_INLINE auto write(OutputIt out, T value,
+ const format_specs<Char>& specs,
+ locale_ref loc) -> OutputIt {
+ if (specs.localized && write_loc(out, value, specs, loc)) return out;
+ return write_int_noinline(out, make_write_int_arg(value, specs.sign), specs,
+ loc);
+}
+// An inlined version of write used in format string compilation.
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_integral<T>::value &&
+ !std::is_same<T, bool>::value &&
+ !std::is_same<OutputIt, buffer_appender<Char>>::value)>
+FMT_CONSTEXPR FMT_INLINE auto write(OutputIt out, T value,
+ const format_specs<Char>& specs,
+ locale_ref loc) -> OutputIt {
+ if (specs.localized && write_loc(out, value, specs, loc)) return out;
+ return write_int(out, make_write_int_arg(value, specs.sign), specs, loc);
+}
+
+// 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;
+ FMT_UNCHECKED_ITERATOR(counting_iterator);
+
+ struct value_type {
+ template <typename T> FMT_CONSTEXPR void operator=(const T&) {}
+ };
+
+ FMT_CONSTEXPR counting_iterator() : count_(0) {}
+
+ FMT_CONSTEXPR auto count() const -> size_t { return count_; }
+
+ FMT_CONSTEXPR auto operator++() -> counting_iterator& {
+ ++count_;
+ return *this;
+ }
+ FMT_CONSTEXPR auto operator++(int) -> counting_iterator {
+ auto it = *this;
+ ++*this;
+ return it;
+ }
+
+ FMT_CONSTEXPR friend auto operator+(counting_iterator it, difference_type n)
+ -> counting_iterator {
+ it.count_ += static_cast<size_t>(n);
+ return it;
+ }
+
+ FMT_CONSTEXPR auto operator*() const -> value_type { return {}; }
+};
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out, basic_string_view<Char> s,
+ const format_specs<Char>& specs) -> OutputIt {
+ 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));
+ bool is_debug = specs.type == presentation_type::debug;
+ size_t width = 0;
+ if (specs.width != 0) {
+ if (is_debug)
+ width = write_escaped_string(counting_iterator{}, s).count();
+ else
+ width = compute_width(basic_string_view<Char>(data, size));
+ }
+ return write_padded(out, specs, size, width,
+ [=](reserve_iterator<OutputIt> it) {
+ if (is_debug) return write_escaped_string(it, s);
+ return copy_str<Char>(data, data + size, it);
+ });
+}
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out,
+ basic_string_view<type_identity_t<Char>> s,
+ const format_specs<Char>& specs, locale_ref)
+ -> OutputIt {
+ return write(out, s, specs);
+}
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out, const Char* s,
+ const format_specs<Char>& specs, locale_ref)
+ -> OutputIt {
+ if (specs.type == presentation_type::pointer)
+ return write_ptr<Char>(out, bit_cast<uintptr_t>(s), &specs);
+ if (!s) throw_format_error("string pointer is null");
+ return write(out, basic_string_view<Char>(s), specs, {});
+}
+
+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)>
+FMT_CONSTEXPR auto write(OutputIt out, T value) -> OutputIt {
+ 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);
+}
+
+// DEPRECATED!
+template <typename Char>
+FMT_CONSTEXPR auto parse_align(const Char* begin, const Char* end,
+ format_specs<Char>& specs) -> const Char* {
+ FMT_ASSERT(begin != end, "");
+ auto align = align::none;
+ auto p = begin + code_point_length(begin);
+ if (end - p <= 0) p = begin;
+ for (;;) {
+ switch (to_ascii(*p)) {
+ case '<':
+ align = align::left;
+ break;
+ case '>':
+ align = align::right;
+ break;
+ case '^':
+ align = align::center;
+ break;
+ }
+ if (align != align::none) {
+ if (p != begin) {
+ auto c = *begin;
+ if (c == '}') return begin;
+ if (c == '{') {
+ throw_format_error("invalid fill character '{'");
+ return begin;
+ }
+ specs.fill = {begin, to_unsigned(p - begin)};
+ begin = p + 1;
+ } else {
+ ++begin;
+ }
+ break;
+ } else if (p == begin) {
+ break;
+ }
+ p = begin;
+ }
+ specs.align = align;
+ return begin;
+}
+
+// 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 showpoint : 1;
+};
+
+template <typename Char>
+FMT_CONSTEXPR auto parse_float_type_spec(const format_specs<Char>& specs)
+ -> float_specs {
+ auto result = float_specs();
+ result.showpoint = specs.alt;
+ result.locale = specs.localized;
+ switch (specs.type) {
+ case presentation_type::none:
+ result.format = float_format::general;
+ break;
+ case presentation_type::general_upper:
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case presentation_type::general_lower:
+ result.format = float_format::general;
+ break;
+ case presentation_type::exp_upper:
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case presentation_type::exp_lower:
+ result.format = float_format::exp;
+ result.showpoint |= specs.precision != 0;
+ break;
+ case presentation_type::fixed_upper:
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case presentation_type::fixed_lower:
+ result.format = float_format::fixed;
+ result.showpoint |= specs.precision != 0;
+ break;
+ case presentation_type::hexfloat_upper:
+ result.upper = true;
+ FMT_FALLTHROUGH;
+ case presentation_type::hexfloat_lower:
+ result.format = float_format::hex;
+ break;
+ default:
+ throw_format_error("invalid format specifier");
+ break;
+ }
+ return result;
+}
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR20 auto write_nonfinite(OutputIt out, bool isnan,
+ format_specs<Char> specs,
+ const float_specs& fspecs) -> OutputIt {
+ auto str =
+ isnan ? (fspecs.upper ? "NAN" : "nan") : (fspecs.upper ? "INF" : "inf");
+ constexpr size_t str_size = 3;
+ auto sign = fspecs.sign;
+ auto size = str_size + (sign ? 1 : 0);
+ // Replace '0'-padding with space for non-finite values.
+ const bool is_zero_fill =
+ specs.fill.size() == 1 && *specs.fill.data() == static_cast<Char>('0');
+ if (is_zero_fill) specs.fill[0] = static_cast<Char>(' ');
+ return write_padded(out, specs, size, [=](reserve_iterator<OutputIt> it) {
+ if (sign) *it++ = detail::sign<Char>(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;
+};
+
+constexpr auto get_significand_size(const big_decimal_fp& f) -> int {
+ return f.significand_size;
+}
+template <typename T>
+inline auto get_significand_size(const dragonbox::decimal_fp<T>& f) -> int {
+ return count_digits(f.significand);
+}
+
+template <typename Char, typename OutputIt>
+constexpr auto write_significand(OutputIt out, const char* significand,
+ int significand_size) -> OutputIt {
+ return copy_str<Char>(significand, significand + significand_size, out);
+}
+template <typename Char, typename OutputIt, typename UInt>
+inline auto write_significand(OutputIt out, UInt significand,
+ int significand_size) -> OutputIt {
+ return format_decimal<Char>(out, significand, significand_size).end;
+}
+template <typename Char, typename OutputIt, typename T, typename Grouping>
+FMT_CONSTEXPR20 auto write_significand(OutputIt out, T significand,
+ int significand_size, int exponent,
+ const Grouping& grouping) -> OutputIt {
+ if (!grouping.has_separator()) {
+ out = write_significand<Char>(out, significand, significand_size);
+ return detail::fill_n(out, exponent, static_cast<Char>('0'));
+ }
+ auto buffer = memory_buffer();
+ write_significand<char>(appender(buffer), significand, significand_size);
+ detail::fill_n(appender(buffer), exponent, '0');
+ return grouping.apply(out, string_view(buffer.data(), buffer.size()));
+}
+
+template <typename Char, typename UInt,
+ FMT_ENABLE_IF(std::is_integral<UInt>::value)>
+inline auto write_significand(Char* out, UInt significand, int significand_size,
+ int integral_size, Char decimal_point) -> Char* {
+ if (!decimal_point)
+ return format_decimal(out, significand, significand_size).end;
+ out += significand_size + 1;
+ Char* end = out;
+ int floating_size = significand_size - integral_size;
+ for (int i = floating_size / 2; i > 0; --i) {
+ out -= 2;
+ copy2(out, digits2(static_cast<std::size_t>(significand % 100)));
+ significand /= 100;
+ }
+ if (floating_size % 2 != 0) {
+ *--out = static_cast<Char>('0' + significand % 10);
+ significand /= 10;
+ }
+ *--out = decimal_point;
+ format_decimal(out - integral_size, significand, integral_size);
+ return end;
+}
+
+template <typename OutputIt, typename UInt, typename Char,
+ FMT_ENABLE_IF(!std::is_pointer<remove_cvref_t<OutputIt>>::value)>
+inline auto write_significand(OutputIt out, UInt significand,
+ int significand_size, int integral_size,
+ Char decimal_point) -> OutputIt {
+ // 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_noinline<Char>(buffer, end, out);
+}
+
+template <typename OutputIt, typename Char>
+FMT_CONSTEXPR auto write_significand(OutputIt out, const char* significand,
+ int significand_size, int integral_size,
+ Char decimal_point) -> OutputIt {
+ out = detail::copy_str_noinline<Char>(significand,
+ significand + integral_size, out);
+ if (!decimal_point) return out;
+ *out++ = decimal_point;
+ return detail::copy_str_noinline<Char>(significand + integral_size,
+ significand + significand_size, out);
+}
+
+template <typename OutputIt, typename Char, typename T, typename Grouping>
+FMT_CONSTEXPR20 auto write_significand(OutputIt out, T significand,
+ int significand_size, int integral_size,
+ Char decimal_point,
+ const Grouping& grouping) -> OutputIt {
+ if (!grouping.has_separator()) {
+ return write_significand(out, significand, significand_size, integral_size,
+ decimal_point);
+ }
+ auto buffer = basic_memory_buffer<Char>();
+ write_significand(buffer_appender<Char>(buffer), significand,
+ significand_size, integral_size, decimal_point);
+ grouping.apply(
+ out, basic_string_view<Char>(buffer.data(), to_unsigned(integral_size)));
+ return detail::copy_str_noinline<Char>(buffer.data() + integral_size,
+ buffer.end(), out);
+}
+
+template <typename OutputIt, typename DecimalFP, typename Char,
+ typename Grouping = digit_grouping<Char>>
+FMT_CONSTEXPR20 auto do_write_float(OutputIt out, const DecimalFP& f,
+ const format_specs<Char>& specs,
+ float_specs fspecs, locale_ref loc)
+ -> OutputIt {
+ auto significand = f.significand;
+ int significand_size = get_significand_size(f);
+ const Char zero = static_cast<Char>('0');
+ auto sign = fspecs.sign;
+ size_t size = to_unsigned(significand_size) + (sign ? 1 : 0);
+ using iterator = reserve_iterator<OutputIt>;
+
+ Char decimal_point =
+ fspecs.locale ? detail::decimal_point<Char>(loc) : static_cast<Char>('.');
+
+ int output_exp = f.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 = fspecs.precision - significand_size;
+ if (num_zeros < 0) num_zeros = 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++ = detail::sign<Char>(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 = detail::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 = f.exponent + significand_size;
+ if (f.exponent >= 0) {
+ // 1234e5 -> 123400000[.0+]
+ size += to_unsigned(f.exponent);
+ int num_zeros = fspecs.precision - exp;
+ abort_fuzzing_if(num_zeros > 5000);
+ if (fspecs.showpoint) {
+ ++size;
+ if (num_zeros <= 0 && fspecs.format != float_format::fixed) num_zeros = 0;
+ if (num_zeros > 0) size += to_unsigned(num_zeros);
+ }
+ auto grouping = Grouping(loc, fspecs.locale);
+ size += to_unsigned(grouping.count_separators(exp));
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = detail::sign<Char>(sign);
+ it = write_significand<Char>(it, significand, significand_size,
+ f.exponent, grouping);
+ if (!fspecs.showpoint) return it;
+ *it++ = decimal_point;
+ return num_zeros > 0 ? detail::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);
+ auto grouping = Grouping(loc, fspecs.locale);
+ size += to_unsigned(grouping.count_separators(exp));
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = detail::sign<Char>(sign);
+ it = write_significand(it, significand, significand_size, exp,
+ decimal_point, grouping);
+ return num_zeros > 0 ? detail::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;
+ }
+ bool pointy = num_zeros != 0 || significand_size != 0 || fspecs.showpoint;
+ size += 1 + (pointy ? 1 : 0) + to_unsigned(num_zeros);
+ return write_padded<align::right>(out, specs, size, [&](iterator it) {
+ if (sign) *it++ = detail::sign<Char>(sign);
+ *it++ = zero;
+ if (!pointy) return it;
+ *it++ = decimal_point;
+ it = detail::fill_n(it, num_zeros, zero);
+ return write_significand<Char>(it, significand, significand_size);
+ });
+}
+
+template <typename Char> class fallback_digit_grouping {
+ public:
+ constexpr fallback_digit_grouping(locale_ref, bool) {}
+
+ constexpr auto has_separator() const -> bool { return false; }
+
+ constexpr auto count_separators(int) const -> int { return 0; }
+
+ template <typename Out, typename C>
+ constexpr auto apply(Out out, basic_string_view<C>) const -> Out {
+ return out;
+ }
+};
+
+template <typename OutputIt, typename DecimalFP, typename Char>
+FMT_CONSTEXPR20 auto write_float(OutputIt out, const DecimalFP& f,
+ const format_specs<Char>& specs,
+ float_specs fspecs, locale_ref loc)
+ -> OutputIt {
+ if (is_constant_evaluated()) {
+ return do_write_float<OutputIt, DecimalFP, Char,
+ fallback_digit_grouping<Char>>(out, f, specs, fspecs,
+ loc);
+ } else {
+ return do_write_float(out, f, specs, fspecs, loc);
+ }
+}
+
+template <typename T> constexpr auto isnan(T value) -> bool {
+ return !(value >= value); // std::isnan doesn't support __float128.
+}
+
+template <typename T, typename Enable = void>
+struct has_isfinite : std::false_type {};
+
+template <typename T>
+struct has_isfinite<T, enable_if_t<sizeof(std::isfinite(T())) != 0>>
+ : std::true_type {};
+
+template <typename T, FMT_ENABLE_IF(std::is_floating_point<T>::value&&
+ has_isfinite<T>::value)>
+FMT_CONSTEXPR20 auto isfinite(T value) -> bool {
+ constexpr T inf = T(std::numeric_limits<double>::infinity());
+ if (is_constant_evaluated())
+ return !detail::isnan(value) && value < inf && value > -inf;
+ return std::isfinite(value);
+}
+template <typename T, FMT_ENABLE_IF(!has_isfinite<T>::value)>
+FMT_CONSTEXPR auto isfinite(T value) -> bool {
+ T inf = T(std::numeric_limits<double>::infinity());
+ // std::isfinite doesn't support __float128.
+ return !detail::isnan(value) && value < inf && value > -inf;
+}
+
+template <typename T, FMT_ENABLE_IF(is_floating_point<T>::value)>
+FMT_INLINE FMT_CONSTEXPR bool signbit(T value) {
+ if (is_constant_evaluated()) {
+#ifdef __cpp_if_constexpr
+ if constexpr (std::numeric_limits<double>::is_iec559) {
+ auto bits = detail::bit_cast<uint64_t>(static_cast<double>(value));
+ return (bits >> (num_bits<uint64_t>() - 1)) != 0;
+ }
+#endif
+ }
+ return std::signbit(static_cast<double>(value));
+}
+
+inline FMT_CONSTEXPR20 void adjust_precision(int& precision, int exp10) {
+ // Adjust fixed precision by exponent because it is relative to decimal
+ // point.
+ if (exp10 > 0 && precision > max_value<int>() - exp10)
+ FMT_THROW(format_error("number is too big"));
+ precision += exp10;
+}
+
+class bigint {
+ private:
+ // A bigint is stored as an array of bigits (big digits), with bigit at index
+ // 0 being the least significant one.
+ using bigit = uint32_t;
+ using double_bigit = uint64_t;
+ enum { bigits_capacity = 32 };
+ basic_memory_buffer<bigit, bigits_capacity> bigits_;
+ int exp_;
+
+ FMT_CONSTEXPR20 auto operator[](int index) const -> bigit {
+ return bigits_[to_unsigned(index)];
+ }
+ FMT_CONSTEXPR20 auto operator[](int index) -> bigit& {
+ return bigits_[to_unsigned(index)];
+ }
+
+ static constexpr const int bigit_bits = num_bits<bigit>();
+
+ friend struct formatter<bigint>;
+
+ FMT_CONSTEXPR20 void subtract_bigits(int index, bigit other, bigit& borrow) {
+ auto result = static_cast<double_bigit>((*this)[index]) - other - borrow;
+ (*this)[index] = static_cast<bigit>(result);
+ borrow = static_cast<bigit>(result >> (bigit_bits * 2 - 1));
+ }
+
+ FMT_CONSTEXPR20 void remove_leading_zeros() {
+ int num_bigits = static_cast<int>(bigits_.size()) - 1;
+ while (num_bigits > 0 && (*this)[num_bigits] == 0) --num_bigits;
+ bigits_.resize(to_unsigned(num_bigits + 1));
+ }
+
+ // Computes *this -= other assuming aligned bigints and *this >= other.
+ FMT_CONSTEXPR20 void subtract_aligned(const bigint& other) {
+ FMT_ASSERT(other.exp_ >= exp_, "unaligned bigints");
+ FMT_ASSERT(compare(*this, other) >= 0, "");
+ bigit borrow = 0;
+ int i = other.exp_ - exp_;
+ for (size_t j = 0, n = other.bigits_.size(); j != n; ++i, ++j)
+ subtract_bigits(i, other.bigits_[j], borrow);
+ while (borrow > 0) subtract_bigits(i, 0, borrow);
+ remove_leading_zeros();
+ }
+
+ FMT_CONSTEXPR20 void multiply(uint32_t value) {
+ const double_bigit wide_value = value;
+ bigit carry = 0;
+ for (size_t i = 0, n = bigits_.size(); i < n; ++i) {
+ double_bigit result = bigits_[i] * wide_value + carry;
+ bigits_[i] = static_cast<bigit>(result);
+ carry = static_cast<bigit>(result >> bigit_bits);
+ }
+ if (carry != 0) bigits_.push_back(carry);
+ }
+
+ template <typename UInt, FMT_ENABLE_IF(std::is_same<UInt, uint64_t>::value ||
+ std::is_same<UInt, uint128_t>::value)>
+ FMT_CONSTEXPR20 void multiply(UInt value) {
+ using half_uint =
+ conditional_t<std::is_same<UInt, uint128_t>::value, uint64_t, uint32_t>;
+ const int shift = num_bits<half_uint>() - bigit_bits;
+ const UInt lower = static_cast<half_uint>(value);
+ const UInt upper = value >> num_bits<half_uint>();
+ UInt carry = 0;
+ for (size_t i = 0, n = bigits_.size(); i < n; ++i) {
+ UInt result = lower * bigits_[i] + static_cast<bigit>(carry);
+ carry = (upper * bigits_[i] << shift) + (result >> bigit_bits) +
+ (carry >> bigit_bits);
+ bigits_[i] = static_cast<bigit>(result);
+ }
+ while (carry != 0) {
+ bigits_.push_back(static_cast<bigit>(carry));
+ carry >>= bigit_bits;
+ }
+ }
+
+ template <typename UInt, FMT_ENABLE_IF(std::is_same<UInt, uint64_t>::value ||
+ std::is_same<UInt, uint128_t>::value)>
+ FMT_CONSTEXPR20 void assign(UInt n) {
+ size_t num_bigits = 0;
+ do {
+ bigits_[num_bigits++] = static_cast<bigit>(n);
+ n >>= bigit_bits;
+ } while (n != 0);
+ bigits_.resize(num_bigits);
+ exp_ = 0;
+ }
+
+ public:
+ FMT_CONSTEXPR20 bigint() : exp_(0) {}
+ explicit bigint(uint64_t n) { assign(n); }
+
+ bigint(const bigint&) = delete;
+ void operator=(const bigint&) = delete;
+
+ FMT_CONSTEXPR20 void assign(const bigint& other) {
+ auto size = other.bigits_.size();
+ bigits_.resize(size);
+ auto data = other.bigits_.data();
+ copy_str<bigit>(data, data + size, bigits_.data());
+ exp_ = other.exp_;
+ }
+
+ template <typename Int> FMT_CONSTEXPR20 void operator=(Int n) {
+ FMT_ASSERT(n > 0, "");
+ assign(uint64_or_128_t<Int>(n));
+ }
+
+ FMT_CONSTEXPR20 auto num_bigits() const -> int {
+ return static_cast<int>(bigits_.size()) + exp_;
+ }
+
+ FMT_NOINLINE FMT_CONSTEXPR20 auto operator<<=(int shift) -> bigint& {
+ FMT_ASSERT(shift >= 0, "");
+ exp_ += shift / bigit_bits;
+ shift %= bigit_bits;
+ if (shift == 0) return *this;
+ bigit carry = 0;
+ for (size_t i = 0, n = bigits_.size(); i < n; ++i) {
+ bigit c = bigits_[i] >> (bigit_bits - shift);
+ bigits_[i] = (bigits_[i] << shift) + carry;
+ carry = c;
+ }
+ if (carry != 0) bigits_.push_back(carry);
+ return *this;
+ }
+
+ template <typename Int>
+ FMT_CONSTEXPR20 auto operator*=(Int value) -> bigint& {
+ FMT_ASSERT(value > 0, "");
+ multiply(uint32_or_64_or_128_t<Int>(value));
+ return *this;
+ }
+
+ friend FMT_CONSTEXPR20 auto compare(const bigint& lhs, const bigint& rhs)
+ -> int {
+ int num_lhs_bigits = lhs.num_bigits(), num_rhs_bigits = rhs.num_bigits();
+ if (num_lhs_bigits != num_rhs_bigits)
+ return num_lhs_bigits > num_rhs_bigits ? 1 : -1;
+ int i = static_cast<int>(lhs.bigits_.size()) - 1;
+ int j = static_cast<int>(rhs.bigits_.size()) - 1;
+ int end = i - j;
+ if (end < 0) end = 0;
+ for (; i >= end; --i, --j) {
+ bigit lhs_bigit = lhs[i], rhs_bigit = rhs[j];
+ if (lhs_bigit != rhs_bigit) return lhs_bigit > rhs_bigit ? 1 : -1;
+ }
+ if (i != j) return i > j ? 1 : -1;
+ return 0;
+ }
+
+ // Returns compare(lhs1 + lhs2, rhs).
+ friend FMT_CONSTEXPR20 auto add_compare(const bigint& lhs1,
+ const bigint& lhs2, const bigint& rhs)
+ -> int {
+ auto minimum = [](int a, int b) { return a < b ? a : b; };
+ auto maximum = [](int a, int b) { return a > b ? a : b; };
+ int max_lhs_bigits = maximum(lhs1.num_bigits(), lhs2.num_bigits());
+ int num_rhs_bigits = rhs.num_bigits();
+ if (max_lhs_bigits + 1 < num_rhs_bigits) return -1;
+ if (max_lhs_bigits > num_rhs_bigits) return 1;
+ auto get_bigit = [](const bigint& n, int i) -> bigit {
+ return i >= n.exp_ && i < n.num_bigits() ? n[i - n.exp_] : 0;
+ };
+ double_bigit borrow = 0;
+ int min_exp = minimum(minimum(lhs1.exp_, lhs2.exp_), rhs.exp_);
+ for (int i = num_rhs_bigits - 1; i >= min_exp; --i) {
+ double_bigit sum =
+ static_cast<double_bigit>(get_bigit(lhs1, i)) + get_bigit(lhs2, i);
+ bigit rhs_bigit = get_bigit(rhs, i);
+ if (sum > rhs_bigit + borrow) return 1;
+ borrow = rhs_bigit + borrow - sum;
+ if (borrow > 1) return -1;
+ borrow <<= bigit_bits;
+ }
+ return borrow != 0 ? -1 : 0;
+ }
+
+ // Assigns pow(10, exp) to this bigint.
+ FMT_CONSTEXPR20 void assign_pow10(int exp) {
+ FMT_ASSERT(exp >= 0, "");
+ if (exp == 0) return *this = 1;
+ // Find the top bit.
+ int bitmask = 1;
+ while (exp >= bitmask) bitmask <<= 1;
+ bitmask >>= 1;
+ // pow(10, exp) = pow(5, exp) * pow(2, exp). First compute pow(5, exp) by
+ // repeated squaring and multiplication.
+ *this = 5;
+ bitmask >>= 1;
+ while (bitmask != 0) {
+ square();
+ if ((exp & bitmask) != 0) *this *= 5;
+ bitmask >>= 1;
+ }
+ *this <<= exp; // Multiply by pow(2, exp) by shifting.
+ }
+
+ FMT_CONSTEXPR20 void square() {
+ int num_bigits = static_cast<int>(bigits_.size());
+ int num_result_bigits = 2 * num_bigits;
+ basic_memory_buffer<bigit, bigits_capacity> n(std::move(bigits_));
+ bigits_.resize(to_unsigned(num_result_bigits));
+ auto sum = uint128_t();
+ for (int bigit_index = 0; bigit_index < num_bigits; ++bigit_index) {
+ // Compute bigit at position bigit_index of the result by adding
+ // cross-product terms n[i] * n[j] such that i + j == bigit_index.
+ for (int i = 0, j = bigit_index; j >= 0; ++i, --j) {
+ // Most terms are multiplied twice which can be optimized in the future.
+ sum += static_cast<double_bigit>(n[i]) * n[j];
+ }
+ (*this)[bigit_index] = static_cast<bigit>(sum);
+ sum >>= num_bits<bigit>(); // Compute the carry.
+ }
+ // Do the same for the top half.
+ for (int bigit_index = num_bigits; bigit_index < num_result_bigits;
+ ++bigit_index) {
+ for (int j = num_bigits - 1, i = bigit_index - j; i < num_bigits;)
+ sum += static_cast<double_bigit>(n[i++]) * n[j--];
+ (*this)[bigit_index] = static_cast<bigit>(sum);
+ sum >>= num_bits<bigit>();
+ }
+ remove_leading_zeros();
+ exp_ *= 2;
+ }
+
+ // If this bigint has a bigger exponent than other, adds trailing zero to make
+ // exponents equal. This simplifies some operations such as subtraction.
+ FMT_CONSTEXPR20 void align(const bigint& other) {
+ int exp_difference = exp_ - other.exp_;
+ if (exp_difference <= 0) return;
+ int num_bigits = static_cast<int>(bigits_.size());
+ bigits_.resize(to_unsigned(num_bigits + exp_difference));
+ for (int i = num_bigits - 1, j = i + exp_difference; i >= 0; --i, --j)
+ bigits_[j] = bigits_[i];
+ std::uninitialized_fill_n(bigits_.data(), exp_difference, 0u);
+ exp_ -= exp_difference;
+ }
+
+ // Divides this bignum by divisor, assigning the remainder to this and
+ // returning the quotient.
+ FMT_CONSTEXPR20 auto divmod_assign(const bigint& divisor) -> int {
+ FMT_ASSERT(this != &divisor, "");
+ if (compare(*this, divisor) < 0) return 0;
+ FMT_ASSERT(divisor.bigits_[divisor.bigits_.size() - 1u] != 0, "");
+ align(divisor);
+ int quotient = 0;
+ do {
+ subtract_aligned(divisor);
+ ++quotient;
+ } while (compare(*this, divisor) >= 0);
+ return quotient;
+ }
+};
+
+// format_dragon flags.
+enum dragon {
+ predecessor_closer = 1,
+ fixup = 2, // Run fixup to correct exp10 which can be off by one.
+ fixed = 4,
+};
+
+// Formats a floating-point number using a variation of the Fixed-Precision
+// Positive Floating-Point Printout ((FPP)^2) algorithm by Steele & White:
+// https://fmt.dev/papers/p372-steele.pdf.
+FMT_CONSTEXPR20 inline void format_dragon(basic_fp<uint128_t> value,
+ unsigned flags, int num_digits,
+ buffer<char>& buf, int& exp10) {
+ bigint numerator; // 2 * R in (FPP)^2.
+ bigint denominator; // 2 * S in (FPP)^2.
+ // lower and upper are differences between value and corresponding boundaries.
+ bigint lower; // (M^- in (FPP)^2).
+ bigint upper_store; // upper's value if different from lower.
+ bigint* upper = nullptr; // (M^+ in (FPP)^2).
+ // Shift numerator and denominator by an extra bit or two (if lower boundary
+ // is closer) to make lower and upper integers. This eliminates multiplication
+ // by 2 during later computations.
+ bool is_predecessor_closer = (flags & dragon::predecessor_closer) != 0;
+ int shift = is_predecessor_closer ? 2 : 1;
+ if (value.e >= 0) {
+ numerator = value.f;
+ numerator <<= value.e + shift;
+ lower = 1;
+ lower <<= value.e;
+ if (is_predecessor_closer) {
+ upper_store = 1;
+ upper_store <<= value.e + 1;
+ upper = &upper_store;
+ }
+ denominator.assign_pow10(exp10);
+ denominator <<= shift;
+ } else if (exp10 < 0) {
+ numerator.assign_pow10(-exp10);
+ lower.assign(numerator);
+ if (is_predecessor_closer) {
+ upper_store.assign(numerator);
+ upper_store <<= 1;
+ upper = &upper_store;
+ }
+ numerator *= value.f;
+ numerator <<= shift;
+ denominator = 1;
+ denominator <<= shift - value.e;
+ } else {
+ numerator = value.f;
+ numerator <<= shift;
+ denominator.assign_pow10(exp10);
+ denominator <<= shift - value.e;
+ lower = 1;
+ if (is_predecessor_closer) {
+ upper_store = 1ULL << 1;
+ upper = &upper_store;
+ }
+ }
+ int even = static_cast<int>((value.f & 1) == 0);
+ if (!upper) upper = &lower;
+ bool shortest = num_digits < 0;
+ if ((flags & dragon::fixup) != 0) {
+ if (add_compare(numerator, *upper, denominator) + even <= 0) {
+ --exp10;
+ numerator *= 10;
+ if (num_digits < 0) {
+ lower *= 10;
+ if (upper != &lower) *upper *= 10;
+ }
+ }
+ if ((flags & dragon::fixed) != 0) adjust_precision(num_digits, exp10 + 1);
+ }
+ // Invariant: value == (numerator / denominator) * pow(10, exp10).
+ if (shortest) {
+ // Generate the shortest representation.
+ num_digits = 0;
+ char* data = buf.data();
+ for (;;) {
+ int digit = numerator.divmod_assign(denominator);
+ bool low = compare(numerator, lower) - even < 0; // numerator <[=] lower.
+ // numerator + upper >[=] pow10:
+ bool high = add_compare(numerator, *upper, denominator) + even > 0;
+ data[num_digits++] = static_cast<char>('0' + digit);
+ if (low || high) {
+ if (!low) {
+ ++data[num_digits - 1];
+ } else if (high) {
+ int result = add_compare(numerator, numerator, denominator);
+ // Round half to even.
+ if (result > 0 || (result == 0 && (digit % 2) != 0))
+ ++data[num_digits - 1];
+ }
+ buf.try_resize(to_unsigned(num_digits));
+ exp10 -= num_digits - 1;
+ return;
+ }
+ numerator *= 10;
+ lower *= 10;
+ if (upper != &lower) *upper *= 10;
+ }
+ }
+ // Generate the given number of digits.
+ exp10 -= num_digits - 1;
+ if (num_digits <= 0) {
+ denominator *= 10;
+ auto digit = add_compare(numerator, numerator, denominator) > 0 ? '1' : '0';
+ buf.push_back(digit);
+ return;
+ }
+ buf.try_resize(to_unsigned(num_digits));
+ for (int i = 0; i < num_digits - 1; ++i) {
+ int digit = numerator.divmod_assign(denominator);
+ buf[i] = static_cast<char>('0' + digit);
+ numerator *= 10;
+ }
+ int digit = numerator.divmod_assign(denominator);
+ auto result = add_compare(numerator, numerator, denominator);
+ if (result > 0 || (result == 0 && (digit % 2) != 0)) {
+ if (digit == 9) {
+ const auto overflow = '0' + 10;
+ buf[num_digits - 1] = overflow;
+ // Propagate the carry.
+ for (int i = num_digits - 1; i > 0 && buf[i] == overflow; --i) {
+ buf[i] = '0';
+ ++buf[i - 1];
+ }
+ if (buf[0] == overflow) {
+ buf[0] = '1';
+ if ((flags & dragon::fixed) != 0)
+ buf.push_back('0');
+ else
+ ++exp10;
+ }
+ return;
+ }
+ ++digit;
+ }
+ buf[num_digits - 1] = static_cast<char>('0' + digit);
+}
+
+// Formats a floating-point number using the hexfloat format.
+template <typename Float, FMT_ENABLE_IF(!is_double_double<Float>::value)>
+FMT_CONSTEXPR20 void format_hexfloat(Float value, int precision,
+ float_specs specs, buffer<char>& buf) {
+ // float is passed as double to reduce the number of instantiations and to
+ // simplify implementation.
+ static_assert(!std::is_same<Float, float>::value, "");
+
+ using info = dragonbox::float_info<Float>;
+
+ // Assume Float is in the format [sign][exponent][significand].
+ using carrier_uint = typename info::carrier_uint;
+
+ constexpr auto num_float_significand_bits =
+ detail::num_significand_bits<Float>();
+
+ basic_fp<carrier_uint> f(value);
+ f.e += num_float_significand_bits;
+ if (!has_implicit_bit<Float>()) --f.e;
+
+ constexpr auto num_fraction_bits =
+ num_float_significand_bits + (has_implicit_bit<Float>() ? 1 : 0);
+ constexpr auto num_xdigits = (num_fraction_bits + 3) / 4;
+
+ constexpr auto leading_shift = ((num_xdigits - 1) * 4);
+ const auto leading_mask = carrier_uint(0xF) << leading_shift;
+ const auto leading_xdigit =
+ static_cast<uint32_t>((f.f & leading_mask) >> leading_shift);
+ if (leading_xdigit > 1) f.e -= (32 - countl_zero(leading_xdigit) - 1);
+
+ int print_xdigits = num_xdigits - 1;
+ if (precision >= 0 && print_xdigits > precision) {
+ const int shift = ((print_xdigits - precision - 1) * 4);
+ const auto mask = carrier_uint(0xF) << shift;
+ const auto v = static_cast<uint32_t>((f.f & mask) >> shift);
+
+ if (v >= 8) {
+ const auto inc = carrier_uint(1) << (shift + 4);
+ f.f += inc;
+ f.f &= ~(inc - 1);
+ }
+
+ // Check long double overflow
+ if (!has_implicit_bit<Float>()) {
+ const auto implicit_bit = carrier_uint(1) << num_float_significand_bits;
+ if ((f.f & implicit_bit) == implicit_bit) {
+ f.f >>= 4;
+ f.e += 4;
+ }
+ }
+
+ print_xdigits = precision;
+ }
+
+ char xdigits[num_bits<carrier_uint>() / 4];
+ detail::fill_n(xdigits, sizeof(xdigits), '0');
+ format_uint<4>(xdigits, f.f, num_xdigits, specs.upper);
+
+ // Remove zero tail
+ while (print_xdigits > 0 && xdigits[print_xdigits] == '0') --print_xdigits;
+
+ buf.push_back('0');
+ buf.push_back(specs.upper ? 'X' : 'x');
+ buf.push_back(xdigits[0]);
+ if (specs.showpoint || print_xdigits > 0 || print_xdigits < precision)
+ buf.push_back('.');
+ buf.append(xdigits + 1, xdigits + 1 + print_xdigits);
+ for (; print_xdigits < precision; ++print_xdigits) buf.push_back('0');
+
+ buf.push_back(specs.upper ? 'P' : 'p');
+
+ uint32_t abs_e;
+ if (f.e < 0) {
+ buf.push_back('-');
+ abs_e = static_cast<uint32_t>(-f.e);
+ } else {
+ buf.push_back('+');
+ abs_e = static_cast<uint32_t>(f.e);
+ }
+ format_decimal<char>(appender(buf), abs_e, detail::count_digits(abs_e));
+}
+
+template <typename Float, FMT_ENABLE_IF(is_double_double<Float>::value)>
+FMT_CONSTEXPR20 void format_hexfloat(Float value, int precision,
+ float_specs specs, buffer<char>& buf) {
+ format_hexfloat(static_cast<double>(value), precision, specs, buf);
+}
+
+constexpr auto fractional_part_rounding_thresholds(int index) -> uint32_t {
+ // For checking rounding thresholds.
+ // The kth entry is chosen to be the smallest integer such that the
+ // upper 32-bits of 10^(k+1) times it is strictly bigger than 5 * 10^k.
+ // It is equal to ceil(2^31 + 2^32/10^(k + 1)).
+ // These are stored in a string literal because we cannot have static arrays
+ // in constexpr functions and non-static ones are poorly optimized.
+ return U"\x9999999a\x828f5c29\x80418938\x80068db9\x8000a7c6\x800010c7"
+ U"\x800001ae\x8000002b"[index];
+}
+
+template <typename Float>
+FMT_CONSTEXPR20 auto format_float(Float value, int precision, float_specs specs,
+ buffer<char>& buf) -> int {
+ // float is passed as double to reduce the number of instantiations.
+ static_assert(!std::is_same<Float, float>::value, "");
+ FMT_ASSERT(value >= 0, "value is negative");
+ auto converted_value = convert_float(value);
+
+ const bool fixed = specs.format == float_format::fixed;
+ if (value <= 0) { // <= instead of == to silence a warning.
+ if (precision <= 0 || !fixed) {
+ buf.push_back('0');
+ return 0;
+ }
+ buf.try_resize(to_unsigned(precision));
+ fill_n(buf.data(), precision, '0');
+ return -precision;
+ }
+
+ int exp = 0;
+ bool use_dragon = true;
+ unsigned dragon_flags = 0;
+ if (!is_fast_float<Float>() || is_constant_evaluated()) {
+ const auto inv_log2_10 = 0.3010299956639812; // 1 / log2(10)
+ using info = dragonbox::float_info<decltype(converted_value)>;
+ const auto f = basic_fp<typename info::carrier_uint>(converted_value);
+ // Compute exp, an approximate power of 10, such that
+ // 10^(exp - 1) <= value < 10^exp or 10^exp <= value < 10^(exp + 1).
+ // This is based on log10(value) == log2(value) / log2(10) and approximation
+ // of log2(value) by e + num_fraction_bits idea from double-conversion.
+ auto e = (f.e + count_digits<1>(f.f) - 1) * inv_log2_10 - 1e-10;
+ exp = static_cast<int>(e);
+ if (e > exp) ++exp; // Compute ceil.
+ dragon_flags = dragon::fixup;
+ } else if (precision < 0) {
+ // Use Dragonbox for the shortest format.
+ if (specs.binary32) {
+ auto dec = dragonbox::to_decimal(static_cast<float>(value));
+ write<char>(buffer_appender<char>(buf), dec.significand);
+ return dec.exponent;
+ }
+ auto dec = dragonbox::to_decimal(static_cast<double>(value));
+ write<char>(buffer_appender<char>(buf), dec.significand);
+ return dec.exponent;
+ } else {
+ // Extract significand bits and exponent bits.
+ using info = dragonbox::float_info<double>;
+ auto br = bit_cast<uint64_t>(static_cast<double>(value));
+
+ const uint64_t significand_mask =
+ (static_cast<uint64_t>(1) << num_significand_bits<double>()) - 1;
+ uint64_t significand = (br & significand_mask);
+ int exponent = static_cast<int>((br & exponent_mask<double>()) >>
+ num_significand_bits<double>());
+
+ if (exponent != 0) { // Check if normal.
+ exponent -= exponent_bias<double>() + num_significand_bits<double>();
+ significand |=
+ (static_cast<uint64_t>(1) << num_significand_bits<double>());
+ significand <<= 1;
+ } else {
+ // Normalize subnormal inputs.
+ FMT_ASSERT(significand != 0, "zeros should not appear here");
+ int shift = countl_zero(significand);
+ FMT_ASSERT(shift >= num_bits<uint64_t>() - num_significand_bits<double>(),
+ "");
+ shift -= (num_bits<uint64_t>() - num_significand_bits<double>() - 2);
+ exponent = (std::numeric_limits<double>::min_exponent -
+ num_significand_bits<double>()) -
+ shift;
+ significand <<= shift;
+ }
+
+ // Compute the first several nonzero decimal significand digits.
+ // We call the number we get the first segment.
+ const int k = info::kappa - dragonbox::floor_log10_pow2(exponent);
+ exp = -k;
+ const int beta = exponent + dragonbox::floor_log2_pow10(k);
+ uint64_t first_segment;
+ bool has_more_segments;
+ int digits_in_the_first_segment;
+ {
+ const auto r = dragonbox::umul192_upper128(
+ significand << beta, dragonbox::get_cached_power(k));
+ first_segment = r.high();
+ has_more_segments = r.low() != 0;
+
+ // The first segment can have 18 ~ 19 digits.
+ if (first_segment >= 1000000000000000000ULL) {
+ digits_in_the_first_segment = 19;
+ } else {
+ // When it is of 18-digits, we align it to 19-digits by adding a bogus
+ // zero at the end.
+ digits_in_the_first_segment = 18;
+ first_segment *= 10;
+ }
+ }
+
+ // Compute the actual number of decimal digits to print.
+ if (fixed) adjust_precision(precision, exp + digits_in_the_first_segment);
+
+ // Use Dragon4 only when there might be not enough digits in the first
+ // segment.
+ if (digits_in_the_first_segment > precision) {
+ use_dragon = false;
+
+ if (precision <= 0) {
+ exp += digits_in_the_first_segment;
+
+ if (precision < 0) {
+ // Nothing to do, since all we have are just leading zeros.
+ buf.try_resize(0);
+ } else {
+ // We may need to round-up.
+ buf.try_resize(1);
+ if ((first_segment | static_cast<uint64_t>(has_more_segments)) >
+ 5000000000000000000ULL) {
+ buf[0] = '1';
+ } else {
+ buf[0] = '0';
+ }
+ }
+ } // precision <= 0
+ else {
+ exp += digits_in_the_first_segment - precision;
+
+ // When precision > 0, we divide the first segment into three
+ // subsegments, each with 9, 9, and 0 ~ 1 digits so that each fits
+ // in 32-bits which usually allows faster calculation than in
+ // 64-bits. Since some compiler (e.g. MSVC) doesn't know how to optimize
+ // division-by-constant for large 64-bit divisors, we do it here
+ // manually. The magic number 7922816251426433760 below is equal to
+ // ceil(2^(64+32) / 10^10).
+ const uint32_t first_subsegment = static_cast<uint32_t>(
+ dragonbox::umul128_upper64(first_segment, 7922816251426433760ULL) >>
+ 32);
+ const uint64_t second_third_subsegments =
+ first_segment - first_subsegment * 10000000000ULL;
+
+ uint64_t prod;
+ uint32_t digits;
+ bool should_round_up;
+ int number_of_digits_to_print = precision > 9 ? 9 : precision;
+
+ // Print a 9-digits subsegment, either the first or the second.
+ auto print_subsegment = [&](uint32_t subsegment, char* buffer) {
+ int number_of_digits_printed = 0;
+
+ // If we want to print an odd number of digits from the subsegment,
+ if ((number_of_digits_to_print & 1) != 0) {
+ // Convert to 64-bit fixed-point fractional form with 1-digit
+ // integer part. The magic number 720575941 is a good enough
+ // approximation of 2^(32 + 24) / 10^8; see
+ // https://jk-jeon.github.io/posts/2022/12/fixed-precision-formatting/#fixed-length-case
+ // for details.
+ prod = ((subsegment * static_cast<uint64_t>(720575941)) >> 24) + 1;
+ digits = static_cast<uint32_t>(prod >> 32);
+ *buffer = static_cast<char>('0' + digits);
+ number_of_digits_printed++;
+ }
+ // If we want to print an even number of digits from the
+ // first_subsegment,
+ else {
+ // Convert to 64-bit fixed-point fractional form with 2-digits
+ // integer part. The magic number 450359963 is a good enough
+ // approximation of 2^(32 + 20) / 10^7; see
+ // https://jk-jeon.github.io/posts/2022/12/fixed-precision-formatting/#fixed-length-case
+ // for details.
+ prod = ((subsegment * static_cast<uint64_t>(450359963)) >> 20) + 1;
+ digits = static_cast<uint32_t>(prod >> 32);
+ copy2(buffer, digits2(digits));
+ number_of_digits_printed += 2;
+ }
+
+ // Print all digit pairs.
+ while (number_of_digits_printed < number_of_digits_to_print) {
+ prod = static_cast<uint32_t>(prod) * static_cast<uint64_t>(100);
+ digits = static_cast<uint32_t>(prod >> 32);
+ copy2(buffer + number_of_digits_printed, digits2(digits));
+ number_of_digits_printed += 2;
+ }
+ };
+
+ // Print first subsegment.
+ print_subsegment(first_subsegment, buf.data());
+
+ // Perform rounding if the first subsegment is the last subsegment to
+ // print.
+ if (precision <= 9) {
+ // Rounding inside the subsegment.
+ // We round-up if:
+ // - either the fractional part is strictly larger than 1/2, or
+ // - the fractional part is exactly 1/2 and the last digit is odd.
+ // We rely on the following observations:
+ // - If fractional_part >= threshold, then the fractional part is
+ // strictly larger than 1/2.
+ // - If the MSB of fractional_part is set, then the fractional part
+ // must be at least 1/2.
+ // - When the MSB of fractional_part is set, either
+ // second_third_subsegments being nonzero or has_more_segments
+ // being true means there are further digits not printed, so the
+ // fractional part is strictly larger than 1/2.
+ if (precision < 9) {
+ uint32_t fractional_part = static_cast<uint32_t>(prod);
+ should_round_up =
+ fractional_part >= fractional_part_rounding_thresholds(
+ 8 - number_of_digits_to_print) ||
+ ((fractional_part >> 31) &
+ ((digits & 1) | (second_third_subsegments != 0) |
+ has_more_segments)) != 0;
+ }
+ // Rounding at the subsegment boundary.
+ // In this case, the fractional part is at least 1/2 if and only if
+ // second_third_subsegments >= 5000000000ULL, and is strictly larger
+ // than 1/2 if we further have either second_third_subsegments >
+ // 5000000000ULL or has_more_segments == true.
+ else {
+ should_round_up = second_third_subsegments > 5000000000ULL ||
+ (second_third_subsegments == 5000000000ULL &&
+ ((digits & 1) != 0 || has_more_segments));
+ }
+ }
+ // Otherwise, print the second subsegment.
+ else {
+ // Compilers are not aware of how to leverage the maximum value of
+ // second_third_subsegments to find out a better magic number which
+ // allows us to eliminate an additional shift. 1844674407370955162 =
+ // ceil(2^64/10) < ceil(2^64*(10^9/(10^10 - 1))).
+ const uint32_t second_subsegment =
+ static_cast<uint32_t>(dragonbox::umul128_upper64(
+ second_third_subsegments, 1844674407370955162ULL));
+ const uint32_t third_subsegment =
+ static_cast<uint32_t>(second_third_subsegments) -
+ second_subsegment * 10;
+
+ number_of_digits_to_print = precision - 9;
+ print_subsegment(second_subsegment, buf.data() + 9);
+
+ // Rounding inside the subsegment.
+ if (precision < 18) {
+ // The condition third_subsegment != 0 implies that the segment was
+ // of 19 digits, so in this case the third segment should be
+ // consisting of a genuine digit from the input.
+ uint32_t fractional_part = static_cast<uint32_t>(prod);
+ should_round_up =
+ fractional_part >= fractional_part_rounding_thresholds(
+ 8 - number_of_digits_to_print) ||
+ ((fractional_part >> 31) &
+ ((digits & 1) | (third_subsegment != 0) |
+ has_more_segments)) != 0;
+ }
+ // Rounding at the subsegment boundary.
+ else {
+ // In this case, the segment must be of 19 digits, thus
+ // the third subsegment should be consisting of a genuine digit from
+ // the input.
+ should_round_up = third_subsegment > 5 ||
+ (third_subsegment == 5 &&
+ ((digits & 1) != 0 || has_more_segments));
+ }
+ }
+
+ // Round-up if necessary.
+ if (should_round_up) {
+ ++buf[precision - 1];
+ for (int i = precision - 1; i > 0 && buf[i] > '9'; --i) {
+ buf[i] = '0';
+ ++buf[i - 1];
+ }
+ if (buf[0] > '9') {
+ buf[0] = '1';
+ if (fixed)
+ buf[precision++] = '0';
+ else
+ ++exp;
+ }
+ }
+ buf.try_resize(to_unsigned(precision));
+ }
+ } // if (digits_in_the_first_segment > precision)
+ else {
+ // Adjust the exponent for its use in Dragon4.
+ exp += digits_in_the_first_segment - 1;
+ }
+ }
+ if (use_dragon) {
+ auto f = basic_fp<uint128_t>();
+ bool is_predecessor_closer = specs.binary32
+ ? f.assign(static_cast<float>(value))
+ : f.assign(converted_value);
+ if (is_predecessor_closer) dragon_flags |= dragon::predecessor_closer;
+ if (fixed) dragon_flags |= dragon::fixed;
+ // Limit precision to the maximum possible number of significant digits in
+ // an IEEE754 double because we don't need to generate zeros.
+ const int max_double_digits = 767;
+ if (precision > max_double_digits) precision = max_double_digits;
+ format_dragon(f, dragon_flags, precision, buf, exp);
+ }
+ if (!fixed && !specs.showpoint) {
+ // Remove trailing zeros.
+ auto num_digits = buf.size();
+ while (num_digits > 0 && buf[num_digits - 1] == '0') {
+ --num_digits;
+ ++exp;
+ }
+ buf.try_resize(num_digits);
+ }
+ return exp;
+}
+template <typename Char, typename OutputIt, typename T>
+FMT_CONSTEXPR20 auto write_float(OutputIt out, T value,
+ format_specs<Char> specs, locale_ref loc)
+ -> OutputIt {
+ float_specs fspecs = parse_float_type_spec(specs);
+ fspecs.sign = specs.sign;
+ if (detail::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 (!detail::isfinite(value))
+ return write_nonfinite(out, detail::isnan(value), specs, fspecs);
+
+ if (specs.align == align::numeric && fspecs.sign) {
+ auto it = reserve(out, 1);
+ *it++ = detail::sign<Char>(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(detail::sign<char>(fspecs.sign));
+ format_hexfloat(convert_float(value), specs.precision, fspecs, buffer);
+ return write_bytes<align::right>(out, {buffer.data(), buffer.size()},
+ specs);
+ }
+ int precision = specs.precision >= 0 || specs.type == presentation_type::none
+ ? specs.precision
+ : 6;
+ if (fspecs.format == float_format::exp) {
+ if (precision == max_value<int>())
+ throw_format_error("number is too big");
+ else
+ ++precision;
+ } else if (fspecs.format != float_format::fixed && precision == 0) {
+ precision = 1;
+ }
+ if (const_check(std::is_same<T, float>())) fspecs.binary32 = true;
+ int exp = format_float(convert_float(value), precision, fspecs, buffer);
+ fspecs.precision = precision;
+ auto f = big_decimal_fp{buffer.data(), static_cast<int>(buffer.size()), exp};
+ return write_float(out, f, specs, fspecs, loc);
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_floating_point<T>::value)>
+FMT_CONSTEXPR20 auto write(OutputIt out, T value, format_specs<Char> specs,
+ locale_ref loc = {}) -> OutputIt {
+ if (const_check(!is_supported_floating_point(value))) return out;
+ return specs.localized && write_loc(out, value, specs, loc)
+ ? out
+ : write_float(out, value, specs, loc);
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_fast_float<T>::value)>
+FMT_CONSTEXPR20 auto write(OutputIt out, T value) -> OutputIt {
+ if (is_constant_evaluated()) return write(out, value, format_specs<Char>());
+ if (const_check(!is_supported_floating_point(value))) return out;
+
+ auto fspecs = float_specs();
+ if (detail::signbit(value)) {
+ fspecs.sign = sign::minus;
+ value = -value;
+ }
+
+ constexpr auto specs = format_specs<Char>();
+ using floaty = conditional_t<std::is_same<T, long double>::value, double, T>;
+ using floaty_uint = typename dragonbox::float_info<floaty>::carrier_uint;
+ floaty_uint mask = exponent_mask<floaty>();
+ if ((bit_cast<floaty_uint>(value) & mask) == mask)
+ return write_nonfinite(out, std::isnan(value), specs, fspecs);
+
+ auto dec = dragonbox::to_decimal(static_cast<floaty>(value));
+ return write_float(out, dec, specs, fspecs, {});
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_floating_point<T>::value &&
+ !is_fast_float<T>::value)>
+inline auto write(OutputIt out, T value) -> OutputIt {
+ return write(out, value, format_specs<Char>());
+}
+
+template <typename Char, typename OutputIt>
+auto write(OutputIt out, monostate, format_specs<Char> = {}, locale_ref = {})
+ -> OutputIt {
+ FMT_ASSERT(false, "");
+ return out;
+}
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out, basic_string_view<Char> value)
+ -> OutputIt {
+ auto it = reserve(out, value.size());
+ it = copy_str_noinline<Char>(value.begin(), value.end(), it);
+ return base_iterator(out, it);
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(is_string<T>::value)>
+constexpr auto write(OutputIt out, const T& value) -> OutputIt {
+ return write<Char>(out, to_string_view(value));
+}
+
+// FMT_ENABLE_IF() condition separated to workaround an MSVC bug.
+template <
+ typename Char, typename OutputIt, typename T,
+ bool check =
+ std::is_enum<T>::value && !std::is_same<T, Char>::value &&
+ mapped_type_constant<T, basic_format_context<OutputIt, Char>>::value !=
+ type::custom_type,
+ FMT_ENABLE_IF(check)>
+FMT_CONSTEXPR auto write(OutputIt out, T value) -> OutputIt {
+ return write<Char>(out, static_cast<underlying_t<T>>(value));
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(std::is_same<T, bool>::value)>
+FMT_CONSTEXPR auto write(OutputIt out, T value,
+ const format_specs<Char>& specs = {}, locale_ref = {})
+ -> OutputIt {
+ return specs.type != presentation_type::none &&
+ specs.type != presentation_type::string
+ ? write(out, value ? 1 : 0, specs, {})
+ : write_bytes(out, value ? "true" : "false", specs);
+}
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR auto write(OutputIt out, Char value) -> OutputIt {
+ auto it = reserve(out, 1);
+ *it++ = value;
+ return base_iterator(out, it);
+}
+
+template <typename Char, typename OutputIt>
+FMT_CONSTEXPR_CHAR_TRAITS auto write(OutputIt out, const Char* value)
+ -> OutputIt {
+ if (value) return write(out, basic_string_view<Char>(value));
+ throw_format_error("string pointer is null");
+ return out;
+}
+
+template <typename Char, typename OutputIt, typename T,
+ FMT_ENABLE_IF(std::is_same<T, void>::value)>
+auto write(OutputIt out, const T* value, const format_specs<Char>& specs = {},
+ locale_ref = {}) -> OutputIt {
+ return write_ptr<Char>(out, bit_cast<uintptr_t>(value), &specs);
+}
+
+// A write overload that handles implicit conversions.
+template <typename Char, typename OutputIt, typename T,
+ typename Context = basic_format_context<OutputIt, Char>>
+FMT_CONSTEXPR auto write(OutputIt out, const T& value) -> enable_if_t<
+ std::is_class<T>::value && !is_string<T>::value &&
+ !is_floating_point<T>::value && !std::is_same<T, Char>::value &&
+ !std::is_same<T, remove_cvref_t<decltype(arg_mapper<Context>().map(
+ value))>>::value,
+ OutputIt> {
+ return write<Char>(out, arg_mapper<Context>().map(value));
+}
+
+template <typename Char, typename OutputIt, typename T,
+ typename Context = basic_format_context<OutputIt, Char>>
+FMT_CONSTEXPR auto write(OutputIt out, const T& value)
+ -> enable_if_t<mapped_type_constant<T, Context>::value == type::custom_type,
+ OutputIt> {
+ auto formatter = typename Context::template formatter_type<T>();
+ auto parse_ctx = typename Context::parse_context_type({});
+ formatter.parse(parse_ctx);
+ auto ctx = Context(out, {}, {});
+ return formatter.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 Char> struct default_arg_formatter {
+ using iterator = buffer_appender<Char>;
+ using context = buffer_context<Char>;
+
+ iterator out;
+ basic_format_args<context> args;
+ locale_ref loc;
+
+ template <typename T> auto operator()(T value) -> iterator {
+ return write<Char>(out, value);
+ }
+ auto operator()(typename basic_format_arg<context>::handle h) -> iterator {
+ basic_format_parse_context<Char> parse_ctx({});
+ context format_ctx(out, args, loc);
+ h.format(parse_ctx, format_ctx);
+ return format_ctx.out();
+ }
+};
+
+template <typename Char> struct arg_formatter {
+ using iterator = buffer_appender<Char>;
+ using context = buffer_context<Char>;
+
+ iterator out;
+ const format_specs<Char>& specs;
+ locale_ref locale;
+
+ template <typename T>
+ FMT_CONSTEXPR FMT_INLINE auto operator()(T value) -> iterator {
+ return detail::write(out, value, specs, locale);
+ }
+ auto operator()(typename basic_format_arg<context>::handle) -> iterator {
+ // User-defined types are handled separately because they require access
+ // to the parse context.
+ return out;
+ }
+};
+
+struct width_checker {
+ template <typename T, FMT_ENABLE_IF(is_integer<T>::value)>
+ FMT_CONSTEXPR auto operator()(T value) -> unsigned long long {
+ if (is_negative(value)) throw_format_error("negative width");
+ return static_cast<unsigned long long>(value);
+ }
+
+ template <typename T, FMT_ENABLE_IF(!is_integer<T>::value)>
+ FMT_CONSTEXPR auto operator()(T) -> unsigned long long {
+ throw_format_error("width is not integer");
+ return 0;
+ }
+};
+
+struct precision_checker {
+ template <typename T, FMT_ENABLE_IF(is_integer<T>::value)>
+ FMT_CONSTEXPR auto operator()(T value) -> unsigned long long {
+ if (is_negative(value)) throw_format_error("negative precision");
+ return static_cast<unsigned long long>(value);
+ }
+
+ template <typename T, FMT_ENABLE_IF(!is_integer<T>::value)>
+ FMT_CONSTEXPR auto operator()(T) -> unsigned long long {
+ throw_format_error("precision is not integer");
+ return 0;
+ }
+};
+
+template <typename Handler, typename FormatArg>
+FMT_CONSTEXPR auto get_dynamic_spec(FormatArg arg) -> int {
+ unsigned long long value = visit_format_arg(Handler(), arg);
+ if (value > to_unsigned(max_value<int>()))
+ throw_format_error("number is too big");
+ return static_cast<int>(value);
+}
+
+template <typename Context, typename ID>
+FMT_CONSTEXPR auto get_arg(Context& ctx, ID id) -> decltype(ctx.arg(id)) {
+ auto arg = ctx.arg(id);
+ if (!arg) ctx.on_error("argument not found");
+ return arg;
+}
+
+template <typename Handler, typename Context>
+FMT_CONSTEXPR 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>(get_arg(ctx, ref.val.index));
+ break;
+ case arg_id_kind::name:
+ value = detail::get_dynamic_spec<Handler>(get_arg(ctx, ref.val.name));
+ break;
+ }
+}
+
+#if FMT_USE_USER_DEFINED_LITERALS
+# if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <typename T, typename Char, size_t N,
+ fmt::detail_exported::fixed_string<Char, N> Str>
+struct statically_named_arg : view {
+ static constexpr auto name = Str.data;
+
+ const T& value;
+ statically_named_arg(const T& v) : value(v) {}
+};
+
+template <typename T, typename Char, size_t N,
+ fmt::detail_exported::fixed_string<Char, N> Str>
+struct is_named_arg<statically_named_arg<T, Char, N, Str>> : std::true_type {};
+
+template <typename T, typename Char, size_t N,
+ fmt::detail_exported::fixed_string<Char, N> Str>
+struct is_statically_named_arg<statically_named_arg<T, Char, N, Str>>
+ : std::true_type {};
+
+template <typename Char, size_t N,
+ fmt::detail_exported::fixed_string<Char, N> Str>
+struct udl_arg {
+ template <typename T> auto operator=(T&& value) const {
+ return statically_named_arg<T, Char, N, Str>(std::forward<T>(value));
+ }
+};
+# else
+template <typename Char> struct udl_arg {
+ const Char* str;
+
+ template <typename T> auto operator=(T&& value) const -> named_arg<Char, T> {
+ return {str, std::forward<T>(value)};
+ }
+};
+# endif
+#endif // FMT_USE_USER_DEFINED_LITERALS
+
+template <typename Locale, typename Char>
+auto vformat(const Locale& loc, basic_string_view<Char> fmt,
+ basic_format_args<buffer_context<type_identity_t<Char>>> args)
+ -> std::basic_string<Char> {
+ auto buf = basic_memory_buffer<Char>();
+ detail::vformat_to(buf, fmt, args, detail::locale_ref(loc));
+ return {buf.data(), buf.size()};
+}
+
+using format_func = void (*)(detail::buffer<char>&, int, const char*);
+
+FMT_API void format_error_code(buffer<char>& out, int error_code,
+ string_view message) noexcept;
+
+FMT_API void report_error(format_func func, int error_code,
+ const char* message) noexcept;
+} // namespace detail
+
+FMT_API auto vsystem_error(int error_code, string_view format_str,
+ format_args args) -> std::system_error;
+
+/**
+ \rst
+ Constructs :class:`std::system_error` with a message formatted with
+ ``fmt::format(fmt, args...)``.
+ *error_code* is a system error code as given by ``errno``.
+
+ **Example**::
+
+ // This throws std::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... T>
+auto system_error(int error_code, format_string<T...> fmt, T&&... args)
+ -> std::system_error {
+ return vsystem_error(error_code, fmt, fmt::make_format_args(args...));
+}
+
+/**
+ \rst
+ Formats an error message for an error returned by an operating system or a
+ language runtime, for example a file opening error, and writes it to *out*.
+ The format is the same as the one used by ``std::system_error(ec, message)``
+ where ``ec`` is ``std::error_code(error_code, std::generic_category()})``.
+ It is implementation-defined but normally looks like:
+
+ .. 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``.
+ \endrst
+ */
+FMT_API void format_system_error(detail::buffer<char>& out, int error_code,
+ const char* message) 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, const char* message) 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> auto format_unsigned(UInt value) -> char* {
+ 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> auto format_signed(Int value) -> char* {
+ 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. */
+ auto size() const -> size_t {
+ return detail::to_unsigned(buffer_ - str_ + buffer_size - 1);
+ }
+
+ /**
+ Returns a pointer to the output buffer content. No terminating null
+ character is appended.
+ */
+ auto data() const -> const char* { return str_; }
+
+ /**
+ Returns a pointer to the output buffer content with terminating null
+ character appended.
+ */
+ auto c_str() const -> const char* {
+ buffer_[buffer_size - 1] = '\0';
+ return str_;
+ }
+
+ /**
+ \rst
+ Returns the content of the output buffer as an ``std::string``.
+ \endrst
+ */
+ auto str() const -> std::string { return std::string(str_, size()); }
+};
+
+template <typename T, typename Char>
+struct formatter<T, Char, enable_if_t<detail::has_format_as<T>::value>>
+ : formatter<detail::format_as_t<T>, Char> {
+ template <typename FormatContext>
+ auto format(const T& value, FormatContext& ctx) const -> decltype(ctx.out()) {
+ using base = formatter<detail::format_as_t<T>, Char>;
+ return base::format(format_as(value), ctx);
+ }
+};
+
+#define FMT_FORMAT_AS(Type, Base) \
+ template <typename Char> \
+ struct formatter<Type, Char> : formatter<Base, Char> {}
+
+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, detail::long_type);
+FMT_FORMAT_AS(unsigned long, detail::ulong_type);
+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>);
+FMT_FORMAT_AS(void*, const void*);
+
+template <typename Char, size_t N>
+struct formatter<Char[N], Char> : formatter<basic_string_view<Char>, Char> {};
+
+/**
+ \rst
+ Converts ``p`` to ``const void*`` for pointer formatting.
+
+ **Example**::
+
+ auto s = fmt::format("{}", fmt::ptr(p));
+ \endrst
+ */
+template <typename T> auto ptr(T p) -> const void* {
+ static_assert(std::is_pointer<T>::value, "");
+ return detail::bit_cast<const void*>(p);
+}
+template <typename T, typename Deleter>
+auto ptr(const std::unique_ptr<T, Deleter>& p) -> const void* {
+ return p.get();
+}
+template <typename T> auto ptr(const std::shared_ptr<T>& p) -> const void* {
+ return p.get();
+}
+
+/**
+ \rst
+ Converts ``e`` to the underlying type.
+
+ **Example**::
+
+ enum class color { red, green, blue };
+ auto s = fmt::format("{}", fmt::underlying(color::red));
+ \endrst
+ */
+template <typename Enum>
+constexpr auto underlying(Enum e) noexcept -> underlying_t<Enum> {
+ return static_cast<underlying_t<Enum>>(e);
+}
+
+namespace enums {
+template <typename Enum, FMT_ENABLE_IF(std::is_enum<Enum>::value)>
+constexpr auto format_as(Enum e) noexcept -> underlying_t<Enum> {
+ return static_cast<underlying_t<Enum>>(e);
+}
+} // namespace enums
+
+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<> specs_;
+
+ public:
+ template <typename ParseContext>
+ FMT_CONSTEXPR auto parse(ParseContext& ctx) -> const char* {
+ return parse_format_specs(ctx.begin(), ctx.end(), specs_, ctx,
+ detail::type::string_type);
+ }
+
+ 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_);
+ }
+};
+
+// group_digits_view is not derived from view because it copies the argument.
+template <typename T> struct group_digits_view {
+ T value;
+};
+
+/**
+ \rst
+ Returns a view that formats an integer value using ',' as a locale-independent
+ thousands separator.
+
+ **Example**::
+
+ fmt::print("{}", fmt::group_digits(12345));
+ // Output: "12,345"
+ \endrst
+ */
+template <typename T> auto group_digits(T value) -> group_digits_view<T> {
+ return {value};
+}
+
+template <typename T> struct formatter<group_digits_view<T>> : formatter<T> {
+ private:
+ detail::dynamic_format_specs<> specs_;
+
+ public:
+ template <typename ParseContext>
+ FMT_CONSTEXPR auto parse(ParseContext& ctx) -> const char* {
+ return parse_format_specs(ctx.begin(), ctx.end(), specs_, ctx,
+ detail::type::int_type);
+ }
+
+ template <typename FormatContext>
+ auto format(group_digits_view<T> t, 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_int(
+ ctx.out(), static_cast<detail::uint64_or_128_t<T>>(t.value), 0, specs_,
+ detail::digit_grouping<char>("\3", ","));
+ }
+};
+
+template <typename T> struct nested_view {
+ const formatter<T>* fmt;
+ const T* value;
+};
+
+template <typename T> struct formatter<nested_view<T>> {
+ FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> const char* {
+ return ctx.begin();
+ }
+ auto format(nested_view<T> view, format_context& ctx) const
+ -> decltype(ctx.out()) {
+ return view.fmt->format(*view.value, ctx);
+ }
+};
+
+template <typename T> struct nested_formatter {
+ private:
+ int width_;
+ detail::fill_t<char> fill_;
+ align_t align_ : 4;
+ formatter<T> formatter_;
+
+ public:
+ constexpr nested_formatter() : width_(0), align_(align_t::none) {}
+
+ FMT_CONSTEXPR auto parse(format_parse_context& ctx) -> const char* {
+ auto specs = detail::dynamic_format_specs<char>();
+ auto it = parse_format_specs(ctx.begin(), ctx.end(), specs, ctx,
+ detail::type::none_type);
+ width_ = specs.width;
+ fill_ = specs.fill;
+ align_ = specs.align;
+ ctx.advance_to(it);
+ return formatter_.parse(ctx);
+ }
+
+ template <typename F>
+ auto write_padded(format_context& ctx, F write) const -> decltype(ctx.out()) {
+ if (width_ == 0) return write(ctx.out());
+ auto buf = memory_buffer();
+ write(std::back_inserter(buf));
+ auto specs = format_specs<>();
+ specs.width = width_;
+ specs.fill = fill_;
+ specs.align = align_;
+ return detail::write(ctx.out(), string_view(buf.data(), buf.size()), specs);
+ }
+
+ auto nested(const T& value) const -> nested_view<T> {
+ return nested_view<T>{&formatter_, &value};
+ }
+};
+
+// DEPRECATED! join_view will be moved to ranges.h.
+template <typename It, typename Sentinel, typename Char = char>
+struct join_view : detail::view {
+ It begin;
+ Sentinel end;
+ basic_string_view<Char> sep;
+
+ join_view(It b, Sentinel e, basic_string_view<Char> s)
+ : begin(b), end(e), sep(s) {}
+};
+
+template <typename It, typename Sentinel, typename Char>
+struct formatter<join_view<It, Sentinel, Char>, Char> {
+ private:
+ using value_type =
+#ifdef __cpp_lib_ranges
+ std::iter_value_t<It>;
+#else
+ typename std::iterator_traits<It>::value_type;
+#endif
+ formatter<remove_cvref_t<value_type>, Char> value_formatter_;
+
+ public:
+ template <typename ParseContext>
+ FMT_CONSTEXPR auto parse(ParseContext& ctx) -> const Char* {
+ return value_formatter_.parse(ctx);
+ }
+
+ template <typename FormatContext>
+ auto format(const join_view<It, Sentinel, Char>& value,
+ FormatContext& ctx) const -> decltype(ctx.out()) {
+ auto it = value.begin;
+ auto out = ctx.out();
+ if (it != value.end) {
+ out = value_formatter_.format(*it, ctx);
+ ++it;
+ while (it != value.end) {
+ out = detail::copy_str<Char>(value.sep.begin(), value.sep.end(), out);
+ ctx.advance_to(out);
+ out = value_formatter_.format(*it, ctx);
+ ++it;
+ }
+ }
+ return out;
+ }
+};
+
+/**
+ Returns a view that formats the iterator range `[begin, end)` with elements
+ separated by `sep`.
+ */
+template <typename It, typename Sentinel>
+auto join(It begin, Sentinel end, string_view sep) -> join_view<It, Sentinel> {
+ return {begin, end, sep};
+}
+
+/**
+ \rst
+ Returns a view 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>
+auto join(Range&& range, string_view sep)
+ -> join_view<detail::iterator_t<Range>, detail::sentinel_t<Range>> {
+ 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 &&
+ !detail::has_format_as<T>::value)>
+inline auto to_string(const T& value) -> std::string {
+ auto buffer = memory_buffer();
+ detail::write<char>(appender(buffer), value);
+ return {buffer.data(), buffer.size()};
+}
+
+template <typename T, FMT_ENABLE_IF(std::is_integral<T>::value)>
+FMT_NODISCARD inline auto to_string(T value) -> std::string {
+ // 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));
+}
+
+template <typename Char, size_t SIZE>
+FMT_NODISCARD auto to_string(const basic_memory_buffer<Char, SIZE>& buf)
+ -> std::basic_string<Char> {
+ auto size = buf.size();
+ detail::assume(size < std::basic_string<Char>().max_size());
+ return std::basic_string<Char>(buf.data(), size);
+}
+
+template <typename T, FMT_ENABLE_IF(!std::is_integral<T>::value &&
+ detail::has_format_as<T>::value)>
+inline auto to_string(const T& value) -> std::string {
+ return to_string(format_as(value));
+}
+
+FMT_END_EXPORT
+
+namespace detail {
+
+template <typename Char>
+void vformat_to(buffer<Char>& buf, basic_string_view<Char> fmt,
+ typename vformat_args<Char>::type args, locale_ref loc) {
+ auto out = buffer_appender<Char>(buf);
+ if (fmt.size() == 2 && equal2(fmt.data(), "{}")) {
+ auto arg = args.get(0);
+ if (!arg) throw_format_error("argument not found");
+ visit_format_arg(default_arg_formatter<Char>{out, args, loc}, arg);
+ return;
+ }
+
+ struct format_handler : error_handler {
+ basic_format_parse_context<Char> parse_context;
+ buffer_context<Char> context;
+
+ format_handler(buffer_appender<Char> p_out, basic_string_view<Char> str,
+ basic_format_args<buffer_context<Char>> p_args,
+ locale_ref p_loc)
+ : parse_context(str), context(p_out, p_args, p_loc) {}
+
+ void on_text(const Char* begin, const Char* end) {
+ auto text = basic_string_view<Char>(begin, to_unsigned(end - begin));
+ context.advance_to(write<Char>(context.out(), text));
+ }
+
+ FMT_CONSTEXPR auto on_arg_id() -> int {
+ return parse_context.next_arg_id();
+ }
+ FMT_CONSTEXPR auto on_arg_id(int id) -> int {
+ return parse_context.check_arg_id(id), id;
+ }
+ FMT_CONSTEXPR auto on_arg_id(basic_string_view<Char> id) -> int {
+ int arg_id = context.arg_id(id);
+ if (arg_id < 0) throw_format_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<Char>{context.out(), context.args(),
+ context.locale()},
+ arg));
+ }
+
+ auto on_format_specs(int id, const Char* begin, const Char* end)
+ -> const Char* {
+ auto arg = get_arg(context, id);
+ // Not using a visitor for custom types gives better codegen.
+ if (arg.format_custom(begin, parse_context, context))
+ return parse_context.begin();
+ auto specs = detail::dynamic_format_specs<Char>();
+ begin = parse_format_specs(begin, end, specs, parse_context, arg.type());
+ detail::handle_dynamic_spec<detail::width_checker>(
+ specs.width, specs.width_ref, context);
+ detail::handle_dynamic_spec<detail::precision_checker>(
+ specs.precision, specs.precision_ref, context);
+ if (begin == end || *begin != '}')
+ throw_format_error("missing '}' in format string");
+ auto f = arg_formatter<Char>{context.out(), specs, context.locale()};
+ context.advance_to(visit_format_arg(f, arg));
+ return begin;
+ }
+ };
+ detail::parse_format_string<false>(fmt, format_handler(out, fmt, args, loc));
+}
+
+FMT_BEGIN_EXPORT
+
+#ifndef FMT_HEADER_ONLY
+extern template FMT_API void vformat_to(buffer<char>&, string_view,
+ typename vformat_args<>::type,
+ locale_ref);
+extern template FMT_API auto thousands_sep_impl<char>(locale_ref)
+ -> thousands_sep_result<char>;
+extern template FMT_API auto thousands_sep_impl<wchar_t>(locale_ref)
+ -> thousands_sep_result<wchar_t>;
+extern template FMT_API auto decimal_point_impl(locale_ref) -> char;
+extern template FMT_API auto decimal_point_impl(locale_ref) -> wchar_t;
+#endif // FMT_HEADER_ONLY
+
+} // namespace detail
+
+#if FMT_USE_USER_DEFINED_LITERALS
+inline namespace literals {
+/**
+ \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
+ */
+# if FMT_USE_NONTYPE_TEMPLATE_ARGS
+template <detail_exported::fixed_string Str> constexpr auto operator""_a() {
+ using char_t = remove_cvref_t<decltype(Str.data[0])>;
+ return detail::udl_arg<char_t, sizeof(Str.data) / sizeof(char_t), Str>();
+}
+# else
+constexpr auto operator""_a(const char* s, size_t) -> detail::udl_arg<char> {
+ return {s};
+}
+# endif
+} // namespace literals
+#endif // FMT_USE_USER_DEFINED_LITERALS
+
+template <typename Locale, FMT_ENABLE_IF(detail::is_locale<Locale>::value)>
+inline auto vformat(const Locale& loc, string_view fmt, format_args args)
+ -> std::string {
+ return detail::vformat(loc, fmt, args);
+}
+
+template <typename Locale, typename... T,
+ FMT_ENABLE_IF(detail::is_locale<Locale>::value)>
+inline auto format(const Locale& loc, format_string<T...> fmt, T&&... args)
+ -> std::string {
+ return fmt::vformat(loc, string_view(fmt), fmt::make_format_args(args...));
+}
+
+template <typename OutputIt, typename Locale,
+ FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value&&
+ detail::is_locale<Locale>::value)>
+auto vformat_to(OutputIt out, const Locale& loc, string_view fmt,
+ format_args args) -> OutputIt {
+ using detail::get_buffer;
+ auto&& buf = get_buffer<char>(out);
+ detail::vformat_to(buf, fmt, args, detail::locale_ref(loc));
+ return detail::get_iterator(buf, out);
+}
+
+template <typename OutputIt, typename Locale, typename... T,
+ FMT_ENABLE_IF(detail::is_output_iterator<OutputIt, char>::value&&
+ detail::is_locale<Locale>::value)>
+FMT_INLINE auto format_to(OutputIt out, const Locale& loc,
+ format_string<T...> fmt, T&&... args) -> OutputIt {
+ return vformat_to(out, loc, fmt, fmt::make_format_args(args...));
+}
+
+template <typename Locale, typename... T,
+ FMT_ENABLE_IF(detail::is_locale<Locale>::value)>
+FMT_NODISCARD FMT_INLINE auto formatted_size(const Locale& loc,
+ format_string<T...> fmt,
+ T&&... args) -> size_t {
+ auto buf = detail::counting_buffer<>();
+ detail::vformat_to<char>(buf, fmt, fmt::make_format_args(args...),
+ detail::locale_ref(loc));
+ return buf.count();
+}
+
+FMT_END_EXPORT
+
+template <typename T, typename Char>
+template <typename FormatContext>
+FMT_CONSTEXPR FMT_INLINE auto
+formatter<T, Char,
+ enable_if_t<detail::type_constant<T, Char>::value !=
+ detail::type::custom_type>>::format(const T& val,
+ FormatContext& ctx)
+ const -> decltype(ctx.out()) {
+ if (specs_.width_ref.kind == detail::arg_id_kind::none &&
+ specs_.precision_ref.kind == detail::arg_id_kind::none) {
+ return detail::write<Char>(ctx.out(), val, specs_, ctx.locale());
+ }
+ auto specs = specs_;
+ 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<Char>(ctx.out(), val, specs, ctx.locale());
+}
+
+FMT_END_NAMESPACE
+
+#ifdef FMT_HEADER_ONLY
+# define FMT_FUNC inline
+# include "format-inl.h"
+#else
+# define FMT_FUNC
+#endif
+
+#endif // FMT_FORMAT_H_
projects / factor.git / blobdiff