From 2a32e43e43b04771a3357d3d4ccbafa7714e0114 Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Fri, 4 Oct 2024 21:21:11 -0700
Subject: [PATCH 4/5] fast_float: Add single header library for from_char
 implementation

Document the process to re-generate the file whenever new release
is made for fast_float upstream.

This would make it work with llvm libc++

Upstream-Status: Submitted [https://gitlab.gnome.org/GNOME/vte/-/issues/2823#note_2239888]
Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
 README.md         |   17 +
 src/fast_float.hh | 3869 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 3886 insertions(+)
 create mode 100644 src/fast_float.hh

diff --git a/README.md b/README.md
index a32465a9..20ed5ba2 100644
--- a/README.md
+++ b/README.md
@@ -21,6 +21,23 @@ on download.gnome.org, but please note that any tarball for releases
 after 0.60.3 were made by either the gnome release team or other
 gnome contributors, but not by a VTE maintainer.
 
+fast_float library[1] is used to provide from_chars implementation for faster
+and more portable parsing of 64 decimal strings.
+
+fast_float.hh is an amalgamation of the entire library,
+which can be regenerated by using amalgamate.py script provided by
+fast_float repository. Following command can be used to re-generate the
+header file
+
+```
+git clone https://github.com/fastfloat/fast_float
+cd fast_float
+git checkout v6.1.6
+python3 ./script/amalgamate.py --license=MIT > $VTE_SRC/src/fast_float.hh
+```
+
+[1]: https://github.com/fastfloat/fast_float
+
 Installation
 ------------
 
diff --git a/src/fast_float.hh b/src/fast_float.hh
new file mode 100644
index 00000000..e0d5dd53
--- /dev/null
+++ b/src/fast_float.hh
@@ -0,0 +1,3869 @@
+// fast_float by Daniel Lemire
+// fast_float by João Paulo Magalhaes
+//
+//
+// with contributions from Eugene Golushkov
+// with contributions from Maksim Kita
+// with contributions from Marcin Wojdyr
+// with contributions from Neal Richardson
+// with contributions from Tim Paine
+// with contributions from Fabio Pellacini
+// with contributions from Lénárd Szolnoki
+// with contributions from Jan Pharago
+// with contributions from Maya Warrier
+// with contributions from Taha Khokhar
+//
+//
+// MIT License Notice
+//
+//    MIT License
+//    
+//    Copyright (c) 2021 The fast_float authors
+//    
+//    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.
+//
+
+#ifndef FASTFLOAT_CONSTEXPR_FEATURE_DETECT_H
+#define FASTFLOAT_CONSTEXPR_FEATURE_DETECT_H
+
+#ifdef __has_include
+#if __has_include(<version>)
+#include <version>
+#endif
+#endif
+
+// Testing for https://wg21.link/N3652, adopted in C++14
+#if __cpp_constexpr >= 201304
+#define FASTFLOAT_CONSTEXPR14 constexpr
+#else
+#define FASTFLOAT_CONSTEXPR14
+#endif
+
+#if defined(__cpp_lib_bit_cast) && __cpp_lib_bit_cast >= 201806L
+#define FASTFLOAT_HAS_BIT_CAST 1
+#else
+#define FASTFLOAT_HAS_BIT_CAST 0
+#endif
+
+#if defined(__cpp_lib_is_constant_evaluated) &&                                \
+    __cpp_lib_is_constant_evaluated >= 201811L
+#define FASTFLOAT_HAS_IS_CONSTANT_EVALUATED 1
+#else
+#define FASTFLOAT_HAS_IS_CONSTANT_EVALUATED 0
+#endif
+
+// Testing for relevant C++20 constexpr library features
+#if FASTFLOAT_HAS_IS_CONSTANT_EVALUATED && FASTFLOAT_HAS_BIT_CAST &&           \
+    __cpp_lib_constexpr_algorithms >= 201806L /*For std::copy and std::fill*/
+#define FASTFLOAT_CONSTEXPR20 constexpr
+#define FASTFLOAT_IS_CONSTEXPR 1
+#else
+#define FASTFLOAT_CONSTEXPR20
+#define FASTFLOAT_IS_CONSTEXPR 0
+#endif
+
+#if __cplusplus >= 201703L || (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)
+#define FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE 0
+#else
+#define FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE 1
+#endif
+
+#endif // FASTFLOAT_CONSTEXPR_FEATURE_DETECT_H
+
+#ifndef FASTFLOAT_FLOAT_COMMON_H
+#define FASTFLOAT_FLOAT_COMMON_H
+
+#include <cfloat>
+#include <cstdint>
+#include <cassert>
+#include <cstring>
+#include <type_traits>
+#include <system_error>
+#ifdef __has_include
+#if __has_include(<stdfloat>) && (__cplusplus > 202002L || _MSVC_LANG > 202002L)
+#include <stdfloat>
+#endif
+#endif
+
+namespace fast_float {
+
+#define FASTFLOAT_JSONFMT (1 << 5)
+#define FASTFLOAT_FORTRANFMT (1 << 6)
+
+enum chars_format {
+  scientific = 1 << 0,
+  fixed = 1 << 2,
+  hex = 1 << 3,
+  no_infnan = 1 << 4,
+  // RFC 8259: https://datatracker.ietf.org/doc/html/rfc8259#section-6
+  json = FASTFLOAT_JSONFMT | fixed | scientific | no_infnan,
+  // Extension of RFC 8259 where, e.g., "inf" and "nan" are allowed.
+  json_or_infnan = FASTFLOAT_JSONFMT | fixed | scientific,
+  fortran = FASTFLOAT_FORTRANFMT | fixed | scientific,
+  general = fixed | scientific
+};
+
+template <typename UC> struct from_chars_result_t {
+  UC const *ptr;
+  std::errc ec;
+};
+using from_chars_result = from_chars_result_t<char>;
+
+template <typename UC> struct parse_options_t {
+  constexpr explicit parse_options_t(chars_format fmt = chars_format::general,
+                                     UC dot = UC('.'))
+      : format(fmt), decimal_point(dot) {}
+
+  /** Which number formats are accepted */
+  chars_format format;
+  /** The character used as decimal point */
+  UC decimal_point;
+};
+using parse_options = parse_options_t<char>;
+
+} // namespace fast_float
+
+#if FASTFLOAT_HAS_BIT_CAST
+#include <bit>
+#endif
+
+#if (defined(__x86_64) || defined(__x86_64__) || defined(_M_X64) ||            \
+     defined(__amd64) || defined(__aarch64__) || defined(_M_ARM64) ||          \
+     defined(__MINGW64__) || defined(__s390x__) ||                             \
+     (defined(__ppc64__) || defined(__PPC64__) || defined(__ppc64le__) ||      \
+      defined(__PPC64LE__)) ||                                                 \
+     defined(__loongarch64))
+#define FASTFLOAT_64BIT 1
+#elif (defined(__i386) || defined(__i386__) || defined(_M_IX86) ||             \
+       defined(__arm__) || defined(_M_ARM) || defined(__ppc__) ||              \
+       defined(__MINGW32__) || defined(__EMSCRIPTEN__))
+#define FASTFLOAT_32BIT 1
+#else
+  // Need to check incrementally, since SIZE_MAX is a size_t, avoid overflow.
+// We can never tell the register width, but the SIZE_MAX is a good
+// approximation. UINTPTR_MAX and INTPTR_MAX are optional, so avoid them for max
+// portability.
+#if SIZE_MAX == 0xffff
+#error Unknown platform (16-bit, unsupported)
+#elif SIZE_MAX == 0xffffffff
+#define FASTFLOAT_32BIT 1
+#elif SIZE_MAX == 0xffffffffffffffff
+#define FASTFLOAT_64BIT 1
+#else
+#error Unknown platform (not 32-bit, not 64-bit?)
+#endif
+#endif
+
+#if ((defined(_WIN32) || defined(_WIN64)) && !defined(__clang__)) ||           \
+    (defined(_M_ARM64) && !defined(__MINGW32__))
+#include <intrin.h>
+#endif
+
+#if defined(_MSC_VER) && !defined(__clang__)
+#define FASTFLOAT_VISUAL_STUDIO 1
+#endif
+
+#if defined __BYTE_ORDER__ && defined __ORDER_BIG_ENDIAN__
+#define FASTFLOAT_IS_BIG_ENDIAN (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
+#elif defined _WIN32
+#define FASTFLOAT_IS_BIG_ENDIAN 0
+#else
+#if defined(__APPLE__) || defined(__FreeBSD__)
+#include <machine/endian.h>
+#elif defined(sun) || defined(__sun)
+#include <sys/byteorder.h>
+#elif defined(__MVS__)
+#include <sys/endian.h>
+#else
+#ifdef __has_include
+#if __has_include(<endian.h>)
+#include <endian.h>
+#endif //__has_include(<endian.h>)
+#endif //__has_include
+#endif
+#
+#ifndef __BYTE_ORDER__
+// safe choice
+#define FASTFLOAT_IS_BIG_ENDIAN 0
+#endif
+#
+#ifndef __ORDER_LITTLE_ENDIAN__
+// safe choice
+#define FASTFLOAT_IS_BIG_ENDIAN 0
+#endif
+#
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define FASTFLOAT_IS_BIG_ENDIAN 0
+#else
+#define FASTFLOAT_IS_BIG_ENDIAN 1
+#endif
+#endif
+
+#if defined(__SSE2__) || (defined(FASTFLOAT_VISUAL_STUDIO) &&                  \
+                          (defined(_M_AMD64) || defined(_M_X64) ||             \
+                           (defined(_M_IX86_FP) && _M_IX86_FP == 2)))
+#define FASTFLOAT_SSE2 1
+#endif
+
+#if defined(__aarch64__) || defined(_M_ARM64)
+#define FASTFLOAT_NEON 1
+#endif
+
+#if defined(FASTFLOAT_SSE2) || defined(FASTFLOAT_NEON)
+#define FASTFLOAT_HAS_SIMD 1
+#endif
+
+#if defined(__GNUC__)
+// disable -Wcast-align=strict (GCC only)
+#define FASTFLOAT_SIMD_DISABLE_WARNINGS                                        \
+  _Pragma("GCC diagnostic push")                                               \
+      _Pragma("GCC diagnostic ignored \"-Wcast-align\"")
+#else
+#define FASTFLOAT_SIMD_DISABLE_WARNINGS
+#endif
+
+#if defined(__GNUC__)
+#define FASTFLOAT_SIMD_RESTORE_WARNINGS _Pragma("GCC diagnostic pop")
+#else
+#define FASTFLOAT_SIMD_RESTORE_WARNINGS
+#endif
+
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#define fastfloat_really_inline __forceinline
+#else
+#define fastfloat_really_inline inline __attribute__((always_inline))
+#endif
+
+#ifndef FASTFLOAT_ASSERT
+#define FASTFLOAT_ASSERT(x)                                                    \
+  { ((void)(x)); }
+#endif
+
+#ifndef FASTFLOAT_DEBUG_ASSERT
+#define FASTFLOAT_DEBUG_ASSERT(x)                                              \
+  { ((void)(x)); }
+#endif
+
+// rust style `try!()` macro, or `?` operator
+#define FASTFLOAT_TRY(x)                                                       \
+  {                                                                            \
+    if (!(x))                                                                  \
+      return false;                                                            \
+  }
+
+#define FASTFLOAT_ENABLE_IF(...)                                               \
+  typename std::enable_if<(__VA_ARGS__), int>::type
+
+namespace fast_float {
+
+fastfloat_really_inline constexpr bool cpp20_and_in_constexpr() {
+#if FASTFLOAT_HAS_IS_CONSTANT_EVALUATED
+  return std::is_constant_evaluated();
+#else
+  return false;
+#endif
+}
+
+template <typename T>
+fastfloat_really_inline constexpr bool is_supported_float_type() {
+  return std::is_same<T, float>::value || std::is_same<T, double>::value
+#if __STDCPP_FLOAT32_T__
+         || std::is_same<T, std::float32_t>::value
+#endif
+#if __STDCPP_FLOAT64_T__
+         || std::is_same<T, std::float64_t>::value
+#endif
+      ;
+}
+
+template <typename UC>
+fastfloat_really_inline constexpr bool is_supported_char_type() {
+  return std::is_same<UC, char>::value || std::is_same<UC, wchar_t>::value ||
+         std::is_same<UC, char16_t>::value || std::is_same<UC, char32_t>::value;
+}
+
+// Compares two ASCII strings in a case insensitive manner.
+template <typename UC>
+inline FASTFLOAT_CONSTEXPR14 bool
+fastfloat_strncasecmp(UC const *input1, UC const *input2, size_t length) {
+  char running_diff{0};
+  for (size_t i = 0; i < length; ++i) {
+    running_diff |= (char(input1[i]) ^ char(input2[i]));
+  }
+  return (running_diff == 0) || (running_diff == 32);
+}
+
+#ifndef FLT_EVAL_METHOD
+#error "FLT_EVAL_METHOD should be defined, please include cfloat."
+#endif
+
+// a pointer and a length to a contiguous block of memory
+template <typename T> struct span {
+  const T *ptr;
+  size_t length;
+  constexpr span(const T *_ptr, size_t _length) : ptr(_ptr), length(_length) {}
+  constexpr span() : ptr(nullptr), length(0) {}
+
+  constexpr size_t len() const noexcept { return length; }
+
+  FASTFLOAT_CONSTEXPR14 const T &operator[](size_t index) const noexcept {
+    FASTFLOAT_DEBUG_ASSERT(index < length);
+    return ptr[index];
+  }
+};
+
+struct value128 {
+  uint64_t low;
+  uint64_t high;
+  constexpr value128(uint64_t _low, uint64_t _high) : low(_low), high(_high) {}
+  constexpr value128() : low(0), high(0) {}
+};
+
+/* Helper C++14 constexpr generic implementation of leading_zeroes */
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 int
+leading_zeroes_generic(uint64_t input_num, int last_bit = 0) {
+  if (input_num & uint64_t(0xffffffff00000000)) {
+    input_num >>= 32;
+    last_bit |= 32;
+  }
+  if (input_num & uint64_t(0xffff0000)) {
+    input_num >>= 16;
+    last_bit |= 16;
+  }
+  if (input_num & uint64_t(0xff00)) {
+    input_num >>= 8;
+    last_bit |= 8;
+  }
+  if (input_num & uint64_t(0xf0)) {
+    input_num >>= 4;
+    last_bit |= 4;
+  }
+  if (input_num & uint64_t(0xc)) {
+    input_num >>= 2;
+    last_bit |= 2;
+  }
+  if (input_num & uint64_t(0x2)) { /* input_num >>=  1; */
+    last_bit |= 1;
+  }
+  return 63 - last_bit;
+}
+
+/* result might be undefined when input_num is zero */
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 int
+leading_zeroes(uint64_t input_num) {
+  assert(input_num > 0);
+  if (cpp20_and_in_constexpr()) {
+    return leading_zeroes_generic(input_num);
+  }
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#if defined(_M_X64) || defined(_M_ARM64)
+  unsigned long leading_zero = 0;
+  // Search the mask data from most significant bit (MSB)
+  // to least significant bit (LSB) for a set bit (1).
+  _BitScanReverse64(&leading_zero, input_num);
+  return (int)(63 - leading_zero);
+#else
+  return leading_zeroes_generic(input_num);
+#endif
+#else
+  return __builtin_clzll(input_num);
+#endif
+}
+
+// slow emulation routine for 32-bit
+fastfloat_really_inline constexpr uint64_t emulu(uint32_t x, uint32_t y) {
+  return x * (uint64_t)y;
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 uint64_t
+umul128_generic(uint64_t ab, uint64_t cd, uint64_t *hi) {
+  uint64_t ad = emulu((uint32_t)(ab >> 32), (uint32_t)cd);
+  uint64_t bd = emulu((uint32_t)ab, (uint32_t)cd);
+  uint64_t adbc = ad + emulu((uint32_t)ab, (uint32_t)(cd >> 32));
+  uint64_t adbc_carry = (uint64_t)(adbc < ad);
+  uint64_t lo = bd + (adbc << 32);
+  *hi = emulu((uint32_t)(ab >> 32), (uint32_t)(cd >> 32)) + (adbc >> 32) +
+        (adbc_carry << 32) + (uint64_t)(lo < bd);
+  return lo;
+}
+
+#ifdef FASTFLOAT_32BIT
+
+// slow emulation routine for 32-bit
+#if !defined(__MINGW64__)
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 uint64_t _umul128(uint64_t ab,
+                                                                uint64_t cd,
+                                                                uint64_t *hi) {
+  return umul128_generic(ab, cd, hi);
+}
+#endif // !__MINGW64__
+
+#endif // FASTFLOAT_32BIT
+
+// compute 64-bit a*b
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 value128
+full_multiplication(uint64_t a, uint64_t b) {
+  if (cpp20_and_in_constexpr()) {
+    value128 answer;
+    answer.low = umul128_generic(a, b, &answer.high);
+    return answer;
+  }
+  value128 answer;
+#if defined(_M_ARM64) && !defined(__MINGW32__)
+  // ARM64 has native support for 64-bit multiplications, no need to emulate
+  // But MinGW on ARM64 doesn't have native support for 64-bit multiplications
+  answer.high = __umulh(a, b);
+  answer.low = a * b;
+#elif defined(FASTFLOAT_32BIT) ||                                              \
+    (defined(_WIN64) && !defined(__clang__) && !defined(_M_ARM64))
+  answer.low = _umul128(a, b, &answer.high); // _umul128 not available on ARM64
+#elif defined(FASTFLOAT_64BIT) && defined(__SIZEOF_INT128__)
+  __uint128_t r = ((__uint128_t)a) * b;
+  answer.low = uint64_t(r);
+  answer.high = uint64_t(r >> 64);
+#else
+  answer.low = umul128_generic(a, b, &answer.high);
+#endif
+  return answer;
+}
+
+struct adjusted_mantissa {
+  uint64_t mantissa{0};
+  int32_t power2{0}; // a negative value indicates an invalid result
+  adjusted_mantissa() = default;
+  constexpr bool operator==(const adjusted_mantissa &o) const {
+    return mantissa == o.mantissa && power2 == o.power2;
+  }
+  constexpr bool operator!=(const adjusted_mantissa &o) const {
+    return mantissa != o.mantissa || power2 != o.power2;
+  }
+};
+
+// Bias so we can get the real exponent with an invalid adjusted_mantissa.
+constexpr static int32_t invalid_am_bias = -0x8000;
+
+// used for binary_format_lookup_tables<T>::max_mantissa
+constexpr uint64_t constant_55555 = 5 * 5 * 5 * 5 * 5;
+
+template <typename T, typename U = void> struct binary_format_lookup_tables;
+
+template <typename T> struct binary_format : binary_format_lookup_tables<T> {
+  using equiv_uint =
+      typename std::conditional<sizeof(T) == 4, uint32_t, uint64_t>::type;
+
+  static inline constexpr int mantissa_explicit_bits();
+  static inline constexpr int minimum_exponent();
+  static inline constexpr int infinite_power();
+  static inline constexpr int sign_index();
+  static inline constexpr int
+  min_exponent_fast_path(); // used when fegetround() == FE_TONEAREST
+  static inline constexpr int max_exponent_fast_path();
+  static inline constexpr int max_exponent_round_to_even();
+  static inline constexpr int min_exponent_round_to_even();
+  static inline constexpr uint64_t max_mantissa_fast_path(int64_t power);
+  static inline constexpr uint64_t
+  max_mantissa_fast_path(); // used when fegetround() == FE_TONEAREST
+  static inline constexpr int largest_power_of_ten();
+  static inline constexpr int smallest_power_of_ten();
+  static inline constexpr T exact_power_of_ten(int64_t power);
+  static inline constexpr size_t max_digits();
+  static inline constexpr equiv_uint exponent_mask();
+  static inline constexpr equiv_uint mantissa_mask();
+  static inline constexpr equiv_uint hidden_bit_mask();
+};
+
+template <typename U> struct binary_format_lookup_tables<double, U> {
+  static constexpr double powers_of_ten[] = {
+      1e0,  1e1,  1e2,  1e3,  1e4,  1e5,  1e6,  1e7,  1e8,  1e9,  1e10, 1e11,
+      1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19, 1e20, 1e21, 1e22};
+
+  // Largest integer value v so that (5**index * v) <= 1<<53.
+  // 0x20000000000000 == 1 << 53
+  static constexpr uint64_t max_mantissa[] = {
+      0x20000000000000,
+      0x20000000000000 / 5,
+      0x20000000000000 / (5 * 5),
+      0x20000000000000 / (5 * 5 * 5),
+      0x20000000000000 / (5 * 5 * 5 * 5),
+      0x20000000000000 / (constant_55555),
+      0x20000000000000 / (constant_55555 * 5),
+      0x20000000000000 / (constant_55555 * 5 * 5),
+      0x20000000000000 / (constant_55555 * 5 * 5 * 5),
+      0x20000000000000 / (constant_55555 * 5 * 5 * 5 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555),
+      0x20000000000000 / (constant_55555 * constant_55555 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * 5 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * 5 * 5 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555 * 5),
+      0x20000000000000 /
+          (constant_55555 * constant_55555 * constant_55555 * 5 * 5),
+      0x20000000000000 /
+          (constant_55555 * constant_55555 * constant_55555 * 5 * 5 * 5),
+      0x20000000000000 /
+          (constant_55555 * constant_55555 * constant_55555 * 5 * 5 * 5 * 5),
+      0x20000000000000 /
+          (constant_55555 * constant_55555 * constant_55555 * constant_55555),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555 *
+                          constant_55555 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555 *
+                          constant_55555 * 5 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555 *
+                          constant_55555 * 5 * 5 * 5),
+      0x20000000000000 / (constant_55555 * constant_55555 * constant_55555 *
+                          constant_55555 * 5 * 5 * 5 * 5)};
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <typename U>
+constexpr double binary_format_lookup_tables<double, U>::powers_of_ten[];
+
+template <typename U>
+constexpr uint64_t binary_format_lookup_tables<double, U>::max_mantissa[];
+
+#endif
+
+template <typename U> struct binary_format_lookup_tables<float, U> {
+  static constexpr float powers_of_ten[] = {1e0f, 1e1f, 1e2f, 1e3f, 1e4f, 1e5f,
+                                            1e6f, 1e7f, 1e8f, 1e9f, 1e10f};
+
+  // Largest integer value v so that (5**index * v) <= 1<<24.
+  // 0x1000000 == 1<<24
+  static constexpr uint64_t max_mantissa[] = {
+      0x1000000,
+      0x1000000 / 5,
+      0x1000000 / (5 * 5),
+      0x1000000 / (5 * 5 * 5),
+      0x1000000 / (5 * 5 * 5 * 5),
+      0x1000000 / (constant_55555),
+      0x1000000 / (constant_55555 * 5),
+      0x1000000 / (constant_55555 * 5 * 5),
+      0x1000000 / (constant_55555 * 5 * 5 * 5),
+      0x1000000 / (constant_55555 * 5 * 5 * 5 * 5),
+      0x1000000 / (constant_55555 * constant_55555),
+      0x1000000 / (constant_55555 * constant_55555 * 5)};
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <typename U>
+constexpr float binary_format_lookup_tables<float, U>::powers_of_ten[];
+
+template <typename U>
+constexpr uint64_t binary_format_lookup_tables<float, U>::max_mantissa[];
+
+#endif
+
+template <>
+inline constexpr int binary_format<double>::min_exponent_fast_path() {
+#if (FLT_EVAL_METHOD != 1) && (FLT_EVAL_METHOD != 0)
+  return 0;
+#else
+  return -22;
+#endif
+}
+
+template <>
+inline constexpr int binary_format<float>::min_exponent_fast_path() {
+#if (FLT_EVAL_METHOD != 1) && (FLT_EVAL_METHOD != 0)
+  return 0;
+#else
+  return -10;
+#endif
+}
+
+template <>
+inline constexpr int binary_format<double>::mantissa_explicit_bits() {
+  return 52;
+}
+template <>
+inline constexpr int binary_format<float>::mantissa_explicit_bits() {
+  return 23;
+}
+
+template <>
+inline constexpr int binary_format<double>::max_exponent_round_to_even() {
+  return 23;
+}
+
+template <>
+inline constexpr int binary_format<float>::max_exponent_round_to_even() {
+  return 10;
+}
+
+template <>
+inline constexpr int binary_format<double>::min_exponent_round_to_even() {
+  return -4;
+}
+
+template <>
+inline constexpr int binary_format<float>::min_exponent_round_to_even() {
+  return -17;
+}
+
+template <> inline constexpr int binary_format<double>::minimum_exponent() {
+  return -1023;
+}
+template <> inline constexpr int binary_format<float>::minimum_exponent() {
+  return -127;
+}
+
+template <> inline constexpr int binary_format<double>::infinite_power() {
+  return 0x7FF;
+}
+template <> inline constexpr int binary_format<float>::infinite_power() {
+  return 0xFF;
+}
+
+template <> inline constexpr int binary_format<double>::sign_index() {
+  return 63;
+}
+template <> inline constexpr int binary_format<float>::sign_index() {
+  return 31;
+}
+
+template <>
+inline constexpr int binary_format<double>::max_exponent_fast_path() {
+  return 22;
+}
+template <>
+inline constexpr int binary_format<float>::max_exponent_fast_path() {
+  return 10;
+}
+
+template <>
+inline constexpr uint64_t binary_format<double>::max_mantissa_fast_path() {
+  return uint64_t(2) << mantissa_explicit_bits();
+}
+template <>
+inline constexpr uint64_t
+binary_format<double>::max_mantissa_fast_path(int64_t power) {
+  // caller is responsible to ensure that
+  // power >= 0 && power <= 22
+  //
+  // Work around clang bug https://godbolt.org/z/zedh7rrhc
+  return (void)max_mantissa[0], max_mantissa[power];
+}
+template <>
+inline constexpr uint64_t binary_format<float>::max_mantissa_fast_path() {
+  return uint64_t(2) << mantissa_explicit_bits();
+}
+template <>
+inline constexpr uint64_t
+binary_format<float>::max_mantissa_fast_path(int64_t power) {
+  // caller is responsible to ensure that
+  // power >= 0 && power <= 10
+  //
+  // Work around clang bug https://godbolt.org/z/zedh7rrhc
+  return (void)max_mantissa[0], max_mantissa[power];
+}
+
+template <>
+inline constexpr double
+binary_format<double>::exact_power_of_ten(int64_t power) {
+  // Work around clang bug https://godbolt.org/z/zedh7rrhc
+  return (void)powers_of_ten[0], powers_of_ten[power];
+}
+template <>
+inline constexpr float binary_format<float>::exact_power_of_ten(int64_t power) {
+  // Work around clang bug https://godbolt.org/z/zedh7rrhc
+  return (void)powers_of_ten[0], powers_of_ten[power];
+}
+
+template <> inline constexpr int binary_format<double>::largest_power_of_ten() {
+  return 308;
+}
+template <> inline constexpr int binary_format<float>::largest_power_of_ten() {
+  return 38;
+}
+
+template <>
+inline constexpr int binary_format<double>::smallest_power_of_ten() {
+  return -342;
+}
+template <> inline constexpr int binary_format<float>::smallest_power_of_ten() {
+  return -64;
+}
+
+template <> inline constexpr size_t binary_format<double>::max_digits() {
+  return 769;
+}
+template <> inline constexpr size_t binary_format<float>::max_digits() {
+  return 114;
+}
+
+template <>
+inline constexpr binary_format<float>::equiv_uint
+binary_format<float>::exponent_mask() {
+  return 0x7F800000;
+}
+template <>
+inline constexpr binary_format<double>::equiv_uint
+binary_format<double>::exponent_mask() {
+  return 0x7FF0000000000000;
+}
+
+template <>
+inline constexpr binary_format<float>::equiv_uint
+binary_format<float>::mantissa_mask() {
+  return 0x007FFFFF;
+}
+template <>
+inline constexpr binary_format<double>::equiv_uint
+binary_format<double>::mantissa_mask() {
+  return 0x000FFFFFFFFFFFFF;
+}
+
+template <>
+inline constexpr binary_format<float>::equiv_uint
+binary_format<float>::hidden_bit_mask() {
+  return 0x00800000;
+}
+template <>
+inline constexpr binary_format<double>::equiv_uint
+binary_format<double>::hidden_bit_mask() {
+  return 0x0010000000000000;
+}
+
+template <typename T>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+to_float(bool negative, adjusted_mantissa am, T &value) {
+  using fastfloat_uint = typename binary_format<T>::equiv_uint;
+  fastfloat_uint word = (fastfloat_uint)am.mantissa;
+  word |= fastfloat_uint(am.power2)
+          << binary_format<T>::mantissa_explicit_bits();
+  word |= fastfloat_uint(negative) << binary_format<T>::sign_index();
+#if FASTFLOAT_HAS_BIT_CAST
+  value = std::bit_cast<T>(word);
+#else
+  ::memcpy(&value, &word, sizeof(T));
+#endif
+}
+
+#ifdef FASTFLOAT_SKIP_WHITE_SPACE // disabled by default
+template <typename = void> struct space_lut {
+  static constexpr bool value[] = {
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <typename T> constexpr bool space_lut<T>::value[];
+
+#endif
+
+inline constexpr bool is_space(uint8_t c) { return space_lut<>::value[c]; }
+#endif
+
+template <typename UC> static constexpr uint64_t int_cmp_zeros() {
+  static_assert((sizeof(UC) == 1) || (sizeof(UC) == 2) || (sizeof(UC) == 4),
+                "Unsupported character size");
+  return (sizeof(UC) == 1) ? 0x3030303030303030
+         : (sizeof(UC) == 2)
+             ? (uint64_t(UC('0')) << 48 | uint64_t(UC('0')) << 32 |
+                uint64_t(UC('0')) << 16 | UC('0'))
+             : (uint64_t(UC('0')) << 32 | UC('0'));
+}
+template <typename UC> static constexpr int int_cmp_len() {
+  return sizeof(uint64_t) / sizeof(UC);
+}
+template <typename UC> static constexpr UC const *str_const_nan() {
+  return nullptr;
+}
+template <> constexpr char const *str_const_nan<char>() { return "nan"; }
+template <> constexpr wchar_t const *str_const_nan<wchar_t>() { return L"nan"; }
+template <> constexpr char16_t const *str_const_nan<char16_t>() {
+  return u"nan";
+}
+template <> constexpr char32_t const *str_const_nan<char32_t>() {
+  return U"nan";
+}
+template <typename UC> static constexpr UC const *str_const_inf() {
+  return nullptr;
+}
+template <> constexpr char const *str_const_inf<char>() { return "infinity"; }
+template <> constexpr wchar_t const *str_const_inf<wchar_t>() {
+  return L"infinity";
+}
+template <> constexpr char16_t const *str_const_inf<char16_t>() {
+  return u"infinity";
+}
+template <> constexpr char32_t const *str_const_inf<char32_t>() {
+  return U"infinity";
+}
+
+template <typename = void> struct int_luts {
+  static constexpr uint8_t chdigit[] = {
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   255, 255,
+      255, 255, 255, 255, 255, 10,  11,  12,  13,  14,  15,  16,  17,  18,  19,
+      20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,  32,  33,  34,
+      35,  255, 255, 255, 255, 255, 255, 10,  11,  12,  13,  14,  15,  16,  17,
+      18,  19,  20,  21,  22,  23,  24,  25,  26,  27,  28,  29,  30,  31,  32,
+      33,  34,  35,  255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      255};
+
+  static constexpr size_t maxdigits_u64[] = {
+      64, 41, 32, 28, 25, 23, 22, 21, 20, 19, 18, 18, 17, 17, 16, 16, 16, 16,
+      15, 15, 15, 15, 14, 14, 14, 14, 14, 14, 14, 13, 13, 13, 13, 13, 13};
+
+  static constexpr uint64_t min_safe_u64[] = {
+      9223372036854775808ull,  12157665459056928801ull, 4611686018427387904,
+      7450580596923828125,     4738381338321616896,     3909821048582988049,
+      9223372036854775808ull,  12157665459056928801ull, 10000000000000000000ull,
+      5559917313492231481,     2218611106740436992,     8650415919381337933,
+      2177953337809371136,     6568408355712890625,     1152921504606846976,
+      2862423051509815793,     6746640616477458432,     15181127029874798299ull,
+      1638400000000000000,     3243919932521508681,     6221821273427820544,
+      11592836324538749809ull, 876488338465357824,      1490116119384765625,
+      2481152873203736576,     4052555153018976267,     6502111422497947648,
+      10260628712958602189ull, 15943230000000000000ull, 787662783788549761,
+      1152921504606846976,     1667889514952984961,     2386420683693101056,
+      3379220508056640625,     4738381338321616896};
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <typename T> constexpr uint8_t int_luts<T>::chdigit[];
+
+template <typename T> constexpr size_t int_luts<T>::maxdigits_u64[];
+
+template <typename T> constexpr uint64_t int_luts<T>::min_safe_u64[];
+
+#endif
+
+template <typename UC>
+fastfloat_really_inline constexpr uint8_t ch_to_digit(UC c) {
+  return int_luts<>::chdigit[static_cast<unsigned char>(c)];
+}
+
+fastfloat_really_inline constexpr size_t max_digits_u64(int base) {
+  return int_luts<>::maxdigits_u64[base - 2];
+}
+
+// If a u64 is exactly max_digits_u64() in length, this is
+// the value below which it has definitely overflowed.
+fastfloat_really_inline constexpr uint64_t min_safe_u64(int base) {
+  return int_luts<>::min_safe_u64[base - 2];
+}
+
+} // namespace fast_float
+
+#endif
+
+
+#ifndef FASTFLOAT_FAST_FLOAT_H
+#define FASTFLOAT_FAST_FLOAT_H
+
+
+namespace fast_float {
+/**
+ * This function parses the character sequence [first,last) for a number. It
+ * parses floating-point numbers expecting a locale-indepent format equivalent
+ * to what is used by std::strtod in the default ("C") locale. The resulting
+ * floating-point value is the closest floating-point values (using either float
+ * or double), using the "round to even" convention for values that would
+ * otherwise fall right in-between two values. That is, we provide exact parsing
+ * according to the IEEE standard.
+ *
+ * Given a successful parse, the pointer (`ptr`) in the returned value is set to
+ * point right after the parsed number, and the `value` referenced is set to the
+ * parsed value. In case of error, the returned `ec` contains a representative
+ * error, otherwise the default (`std::errc()`) value is stored.
+ *
+ * The implementation does not throw and does not allocate memory (e.g., with
+ * `new` or `malloc`).
+ *
+ * Like the C++17 standard, the `fast_float::from_chars` functions take an
+ * optional last argument of the type `fast_float::chars_format`. It is a bitset
+ * value: we check whether `fmt & fast_float::chars_format::fixed` and `fmt &
+ * fast_float::chars_format::scientific` are set to determine whether we allow
+ * the fixed point and scientific notation respectively. The default is
+ * `fast_float::chars_format::general` which allows both `fixed` and
+ * `scientific`.
+ */
+template <typename T, typename UC = char,
+          typename = FASTFLOAT_ENABLE_IF(is_supported_float_type<T>())>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars(UC const *first, UC const *last, T &value,
+           chars_format fmt = chars_format::general) noexcept;
+
+/**
+ * Like from_chars, but accepts an `options` argument to govern number parsing.
+ */
+template <typename T, typename UC = char>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars_advanced(UC const *first, UC const *last, T &value,
+                    parse_options_t<UC> options) noexcept;
+/**
+ * from_chars for integer types.
+ */
+template <typename T, typename UC = char,
+          typename = FASTFLOAT_ENABLE_IF(!is_supported_float_type<T>())>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars(UC const *first, UC const *last, T &value, int base = 10) noexcept;
+
+} // namespace fast_float
+#endif // FASTFLOAT_FAST_FLOAT_H
+
+#ifndef FASTFLOAT_ASCII_NUMBER_H
+#define FASTFLOAT_ASCII_NUMBER_H
+
+#include <cctype>
+#include <cstdint>
+#include <cstring>
+#include <iterator>
+#include <limits>
+#include <type_traits>
+
+
+#ifdef FASTFLOAT_SSE2
+#include <emmintrin.h>
+#endif
+
+#ifdef FASTFLOAT_NEON
+#include <arm_neon.h>
+#endif
+
+namespace fast_float {
+
+template <typename UC> fastfloat_really_inline constexpr bool has_simd_opt() {
+#ifdef FASTFLOAT_HAS_SIMD
+  return std::is_same<UC, char16_t>::value;
+#else
+  return false;
+#endif
+}
+
+// Next function can be micro-optimized, but compilers are entirely
+// able to optimize it well.
+template <typename UC>
+fastfloat_really_inline constexpr bool is_integer(UC c) noexcept {
+  return !(c > UC('9') || c < UC('0'));
+}
+
+fastfloat_really_inline constexpr uint64_t byteswap(uint64_t val) {
+  return (val & 0xFF00000000000000) >> 56 | (val & 0x00FF000000000000) >> 40 |
+         (val & 0x0000FF0000000000) >> 24 | (val & 0x000000FF00000000) >> 8 |
+         (val & 0x00000000FF000000) << 8 | (val & 0x0000000000FF0000) << 24 |
+         (val & 0x000000000000FF00) << 40 | (val & 0x00000000000000FF) << 56;
+}
+
+// Read 8 UC into a u64. Truncates UC if not char.
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+read8_to_u64(const UC *chars) {
+  if (cpp20_and_in_constexpr() || !std::is_same<UC, char>::value) {
+    uint64_t val = 0;
+    for (int i = 0; i < 8; ++i) {
+      val |= uint64_t(uint8_t(*chars)) << (i * 8);
+      ++chars;
+    }
+    return val;
+  }
+  uint64_t val;
+  ::memcpy(&val, chars, sizeof(uint64_t));
+#if FASTFLOAT_IS_BIG_ENDIAN == 1
+  // Need to read as-if the number was in little-endian order.
+  val = byteswap(val);
+#endif
+  return val;
+}
+
+#ifdef FASTFLOAT_SSE2
+
+fastfloat_really_inline uint64_t simd_read8_to_u64(const __m128i data) {
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  const __m128i packed = _mm_packus_epi16(data, data);
+#ifdef FASTFLOAT_64BIT
+  return uint64_t(_mm_cvtsi128_si64(packed));
+#else
+  uint64_t value;
+  // Visual Studio + older versions of GCC don't support _mm_storeu_si64
+  _mm_storel_epi64(reinterpret_cast<__m128i *>(&value), packed);
+  return value;
+#endif
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+}
+
+fastfloat_really_inline uint64_t simd_read8_to_u64(const char16_t *chars) {
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  return simd_read8_to_u64(
+      _mm_loadu_si128(reinterpret_cast<const __m128i *>(chars)));
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+}
+
+#elif defined(FASTFLOAT_NEON)
+
+fastfloat_really_inline uint64_t simd_read8_to_u64(const uint16x8_t data) {
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  uint8x8_t utf8_packed = vmovn_u16(data);
+  return vget_lane_u64(vreinterpret_u64_u8(utf8_packed), 0);
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+}
+
+fastfloat_really_inline uint64_t simd_read8_to_u64(const char16_t *chars) {
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  return simd_read8_to_u64(
+      vld1q_u16(reinterpret_cast<const uint16_t *>(chars)));
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+}
+
+#endif // FASTFLOAT_SSE2
+
+// MSVC SFINAE is broken pre-VS2017
+#if defined(_MSC_VER) && _MSC_VER <= 1900
+template <typename UC>
+#else
+template <typename UC, FASTFLOAT_ENABLE_IF(!has_simd_opt<UC>()) = 0>
+#endif
+// dummy for compile
+uint64_t simd_read8_to_u64(UC const *) {
+  return 0;
+}
+
+// credit  @aqrit
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 uint32_t
+parse_eight_digits_unrolled(uint64_t val) {
+  const uint64_t mask = 0x000000FF000000FF;
+  const uint64_t mul1 = 0x000F424000000064; // 100 + (1000000ULL << 32)
+  const uint64_t mul2 = 0x0000271000000001; // 1 + (10000ULL << 32)
+  val -= 0x3030303030303030;
+  val = (val * 10) + (val >> 8); // val = (val * 2561) >> 8;
+  val = (((val & mask) * mul1) + (((val >> 16) & mask) * mul2)) >> 32;
+  return uint32_t(val);
+}
+
+// Call this if chars are definitely 8 digits.
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint32_t
+parse_eight_digits_unrolled(UC const *chars) noexcept {
+  if (cpp20_and_in_constexpr() || !has_simd_opt<UC>()) {
+    return parse_eight_digits_unrolled(read8_to_u64(chars)); // truncation okay
+  }
+  return parse_eight_digits_unrolled(simd_read8_to_u64(chars));
+}
+
+// credit @aqrit
+fastfloat_really_inline constexpr bool
+is_made_of_eight_digits_fast(uint64_t val) noexcept {
+  return !((((val + 0x4646464646464646) | (val - 0x3030303030303030)) &
+            0x8080808080808080));
+}
+
+#ifdef FASTFLOAT_HAS_SIMD
+
+// Call this if chars might not be 8 digits.
+// Using this style (instead of is_made_of_eight_digits_fast() then
+// parse_eight_digits_unrolled()) ensures we don't load SIMD registers twice.
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 bool
+simd_parse_if_eight_digits_unrolled(const char16_t *chars,
+                                    uint64_t &i) noexcept {
+  if (cpp20_and_in_constexpr()) {
+    return false;
+  }
+#ifdef FASTFLOAT_SSE2
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  const __m128i data =
+      _mm_loadu_si128(reinterpret_cast<const __m128i *>(chars));
+
+  // (x - '0') <= 9
+  // http://0x80.pl/articles/simd-parsing-int-sequences.html
+  const __m128i t0 = _mm_add_epi16(data, _mm_set1_epi16(32720));
+  const __m128i t1 = _mm_cmpgt_epi16(t0, _mm_set1_epi16(-32759));
+
+  if (_mm_movemask_epi8(t1) == 0) {
+    i = i * 100000000 + parse_eight_digits_unrolled(simd_read8_to_u64(data));
+    return true;
+  } else
+    return false;
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+#elif defined(FASTFLOAT_NEON)
+  FASTFLOAT_SIMD_DISABLE_WARNINGS
+  const uint16x8_t data = vld1q_u16(reinterpret_cast<const uint16_t *>(chars));
+
+  // (x - '0') <= 9
+  // http://0x80.pl/articles/simd-parsing-int-sequences.html
+  const uint16x8_t t0 = vsubq_u16(data, vmovq_n_u16('0'));
+  const uint16x8_t mask = vcltq_u16(t0, vmovq_n_u16('9' - '0' + 1));
+
+  if (vminvq_u16(mask) == 0xFFFF) {
+    i = i * 100000000 + parse_eight_digits_unrolled(simd_read8_to_u64(data));
+    return true;
+  } else
+    return false;
+  FASTFLOAT_SIMD_RESTORE_WARNINGS
+#else
+  (void)chars;
+  (void)i;
+  return false;
+#endif // FASTFLOAT_SSE2
+}
+
+#endif // FASTFLOAT_HAS_SIMD
+
+// MSVC SFINAE is broken pre-VS2017
+#if defined(_MSC_VER) && _MSC_VER <= 1900
+template <typename UC>
+#else
+template <typename UC, FASTFLOAT_ENABLE_IF(!has_simd_opt<UC>()) = 0>
+#endif
+// dummy for compile
+bool simd_parse_if_eight_digits_unrolled(UC const *, uint64_t &) {
+  return 0;
+}
+
+template <typename UC, FASTFLOAT_ENABLE_IF(!std::is_same<UC, char>::value) = 0>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+loop_parse_if_eight_digits(const UC *&p, const UC *const pend, uint64_t &i) {
+  if (!has_simd_opt<UC>()) {
+    return;
+  }
+  while ((std::distance(p, pend) >= 8) &&
+         simd_parse_if_eight_digits_unrolled(
+             p, i)) { // in rare cases, this will overflow, but that's ok
+    p += 8;
+  }
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+loop_parse_if_eight_digits(const char *&p, const char *const pend,
+                           uint64_t &i) {
+  // optimizes better than parse_if_eight_digits_unrolled() for UC = char.
+  while ((std::distance(p, pend) >= 8) &&
+         is_made_of_eight_digits_fast(read8_to_u64(p))) {
+    i = i * 100000000 +
+        parse_eight_digits_unrolled(read8_to_u64(
+            p)); // in rare cases, this will overflow, but that's ok
+    p += 8;
+  }
+}
+
+enum class parse_error {
+  no_error,
+  // [JSON-only] The minus sign must be followed by an integer.
+  missing_integer_after_sign,
+  // A sign must be followed by an integer or dot.
+  missing_integer_or_dot_after_sign,
+  // [JSON-only] The integer part must not have leading zeros.
+  leading_zeros_in_integer_part,
+  // [JSON-only] The integer part must have at least one digit.
+  no_digits_in_integer_part,
+  // [JSON-only] If there is a decimal point, there must be digits in the
+  // fractional part.
+  no_digits_in_fractional_part,
+  // The mantissa must have at least one digit.
+  no_digits_in_mantissa,
+  // Scientific notation requires an exponential part.
+  missing_exponential_part,
+};
+
+template <typename UC> struct parsed_number_string_t {
+  int64_t exponent{0};
+  uint64_t mantissa{0};
+  UC const *lastmatch{nullptr};
+  bool negative{false};
+  bool valid{false};
+  bool too_many_digits{false};
+  // contains the range of the significant digits
+  span<const UC> integer{};  // non-nullable
+  span<const UC> fraction{}; // nullable
+  parse_error error{parse_error::no_error};
+};
+
+using byte_span = span<const char>;
+using parsed_number_string = parsed_number_string_t<char>;
+
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 parsed_number_string_t<UC>
+report_parse_error(UC const *p, parse_error error) {
+  parsed_number_string_t<UC> answer;
+  answer.valid = false;
+  answer.lastmatch = p;
+  answer.error = error;
+  return answer;
+}
+
+// Assuming that you use no more than 19 digits, this will
+// parse an ASCII string.
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 parsed_number_string_t<UC>
+parse_number_string(UC const *p, UC const *pend,
+                    parse_options_t<UC> options) noexcept {
+  chars_format const fmt = options.format;
+  UC const decimal_point = options.decimal_point;
+
+  parsed_number_string_t<UC> answer;
+  answer.valid = false;
+  answer.too_many_digits = false;
+  answer.negative = (*p == UC('-'));
+#ifdef FASTFLOAT_ALLOWS_LEADING_PLUS // disabled by default
+  if ((*p == UC('-')) || (!(fmt & FASTFLOAT_JSONFMT) && *p == UC('+'))) {
+#else
+  if (*p == UC('-')) { // C++17 20.19.3.(7.1) explicitly forbids '+' sign here
+#endif
+    ++p;
+    if (p == pend) {
+      return report_parse_error<UC>(
+          p, parse_error::missing_integer_or_dot_after_sign);
+    }
+    if (fmt & FASTFLOAT_JSONFMT) {
+      if (!is_integer(*p)) { // a sign must be followed by an integer
+        return report_parse_error<UC>(p,
+                                      parse_error::missing_integer_after_sign);
+      }
+    } else {
+      if (!is_integer(*p) &&
+          (*p !=
+           decimal_point)) { // a sign must be followed by an integer or the dot
+        return report_parse_error<UC>(
+            p, parse_error::missing_integer_or_dot_after_sign);
+      }
+    }
+  }
+  UC const *const start_digits = p;
+
+  uint64_t i = 0; // an unsigned int avoids signed overflows (which are bad)
+
+  while ((p != pend) && is_integer(*p)) {
+    // a multiplication by 10 is cheaper than an arbitrary integer
+    // multiplication
+    i = 10 * i +
+        uint64_t(*p -
+                 UC('0')); // might overflow, we will handle the overflow later
+    ++p;
+  }
+  UC const *const end_of_integer_part = p;
+  int64_t digit_count = int64_t(end_of_integer_part - start_digits);
+  answer.integer = span<const UC>(start_digits, size_t(digit_count));
+  if (fmt & FASTFLOAT_JSONFMT) {
+    // at least 1 digit in integer part, without leading zeros
+    if (digit_count == 0) {
+      return report_parse_error<UC>(p, parse_error::no_digits_in_integer_part);
+    }
+    if ((start_digits[0] == UC('0') && digit_count > 1)) {
+      return report_parse_error<UC>(start_digits,
+                                    parse_error::leading_zeros_in_integer_part);
+    }
+  }
+
+  int64_t exponent = 0;
+  const bool has_decimal_point = (p != pend) && (*p == decimal_point);
+  if (has_decimal_point) {
+    ++p;
+    UC const *before = p;
+    // can occur at most twice without overflowing, but let it occur more, since
+    // for integers with many digits, digit parsing is the primary bottleneck.
+    loop_parse_if_eight_digits(p, pend, i);
+
+    while ((p != pend) && is_integer(*p)) {
+      uint8_t digit = uint8_t(*p - UC('0'));
+      ++p;
+      i = i * 10 + digit; // in rare cases, this will overflow, but that's ok
+    }
+    exponent = before - p;
+    answer.fraction = span<const UC>(before, size_t(p - before));
+    digit_count -= exponent;
+  }
+  if (fmt & FASTFLOAT_JSONFMT) {
+    // at least 1 digit in fractional part
+    if (has_decimal_point && exponent == 0) {
+      return report_parse_error<UC>(p,
+                                    parse_error::no_digits_in_fractional_part);
+    }
+  } else if (digit_count ==
+             0) { // we must have encountered at least one integer!
+    return report_parse_error<UC>(p, parse_error::no_digits_in_mantissa);
+  }
+  int64_t exp_number = 0; // explicit exponential part
+  if (((fmt & chars_format::scientific) && (p != pend) &&
+       ((UC('e') == *p) || (UC('E') == *p))) ||
+      ((fmt & FASTFLOAT_FORTRANFMT) && (p != pend) &&
+       ((UC('+') == *p) || (UC('-') == *p) || (UC('d') == *p) ||
+        (UC('D') == *p)))) {
+    UC const *location_of_e = p;
+    if ((UC('e') == *p) || (UC('E') == *p) || (UC('d') == *p) ||
+        (UC('D') == *p)) {
+      ++p;
+    }
+    bool neg_exp = false;
+    if ((p != pend) && (UC('-') == *p)) {
+      neg_exp = true;
+      ++p;
+    } else if ((p != pend) &&
+               (UC('+') ==
+                *p)) { // '+' on exponent is allowed by C++17 20.19.3.(7.1)
+      ++p;
+    }
+    if ((p == pend) || !is_integer(*p)) {
+      if (!(fmt & chars_format::fixed)) {
+        // The exponential part is invalid for scientific notation, so it must
+        // be a trailing token for fixed notation. However, fixed notation is
+        // disabled, so report a scientific notation error.
+        return report_parse_error<UC>(p, parse_error::missing_exponential_part);
+      }
+      // Otherwise, we will be ignoring the 'e'.
+      p = location_of_e;
+    } else {
+      while ((p != pend) && is_integer(*p)) {
+        uint8_t digit = uint8_t(*p - UC('0'));
+        if (exp_number < 0x10000000) {
+          exp_number = 10 * exp_number + digit;
+        }
+        ++p;
+      }
+      if (neg_exp) {
+        exp_number = -exp_number;
+      }
+      exponent += exp_number;
+    }
+  } else {
+    // If it scientific and not fixed, we have to bail out.
+    if ((fmt & chars_format::scientific) && !(fmt & chars_format::fixed)) {
+      return report_parse_error<UC>(p, parse_error::missing_exponential_part);
+    }
+  }
+  answer.lastmatch = p;
+  answer.valid = true;
+
+  // If we frequently had to deal with long strings of digits,
+  // we could extend our code by using a 128-bit integer instead
+  // of a 64-bit integer. However, this is uncommon.
+  //
+  // We can deal with up to 19 digits.
+  if (digit_count > 19) { // this is uncommon
+    // It is possible that the integer had an overflow.
+    // We have to handle the case where we have 0.0000somenumber.
+    // We need to be mindful of the case where we only have zeroes...
+    // E.g., 0.000000000...000.
+    UC const *start = start_digits;
+    while ((start != pend) && (*start == UC('0') || *start == decimal_point)) {
+      if (*start == UC('0')) {
+        digit_count--;
+      }
+      start++;
+    }
+
+    if (digit_count > 19) {
+      answer.too_many_digits = true;
+      // Let us start again, this time, avoiding overflows.
+      // We don't need to check if is_integer, since we use the
+      // pre-tokenized spans from above.
+      i = 0;
+      p = answer.integer.ptr;
+      UC const *int_end = p + answer.integer.len();
+      const uint64_t minimal_nineteen_digit_integer{1000000000000000000};
+      while ((i < minimal_nineteen_digit_integer) && (p != int_end)) {
+        i = i * 10 + uint64_t(*p - UC('0'));
+        ++p;
+      }
+      if (i >= minimal_nineteen_digit_integer) { // We have a big integers
+        exponent = end_of_integer_part - p + exp_number;
+      } else { // We have a value with a fractional component.
+        p = answer.fraction.ptr;
+        UC const *frac_end = p + answer.fraction.len();
+        while ((i < minimal_nineteen_digit_integer) && (p != frac_end)) {
+          i = i * 10 + uint64_t(*p - UC('0'));
+          ++p;
+        }
+        exponent = answer.fraction.ptr - p + exp_number;
+      }
+      // We have now corrected both exponent and i, to a truncated value
+    }
+  }
+  answer.exponent = exponent;
+  answer.mantissa = i;
+  return answer;
+}
+
+template <typename T, typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+parse_int_string(UC const *p, UC const *pend, T &value, int base) {
+  from_chars_result_t<UC> answer;
+
+  UC const *const first = p;
+
+  bool negative = (*p == UC('-'));
+  if (!std::is_signed<T>::value && negative) {
+    answer.ec = std::errc::invalid_argument;
+    answer.ptr = first;
+    return answer;
+  }
+#ifdef FASTFLOAT_ALLOWS_LEADING_PLUS // disabled by default
+  if ((*p == UC('-')) || (*p == UC('+'))) {
+#else
+  if (*p == UC('-')) {
+#endif
+    ++p;
+  }
+
+  UC const *const start_num = p;
+
+  while (p != pend && *p == UC('0')) {
+    ++p;
+  }
+
+  const bool has_leading_zeros = p > start_num;
+
+  UC const *const start_digits = p;
+
+  uint64_t i = 0;
+  if (base == 10) {
+    loop_parse_if_eight_digits(p, pend, i); // use SIMD if possible
+  }
+  while (p != pend) {
+    uint8_t digit = ch_to_digit(*p);
+    if (digit >= base) {
+      break;
+    }
+    i = uint64_t(base) * i + digit; // might overflow, check this later
+    p++;
+  }
+
+  size_t digit_count = size_t(p - start_digits);
+
+  if (digit_count == 0) {
+    if (has_leading_zeros) {
+      value = 0;
+      answer.ec = std::errc();
+      answer.ptr = p;
+    } else {
+      answer.ec = std::errc::invalid_argument;
+      answer.ptr = first;
+    }
+    return answer;
+  }
+
+  answer.ptr = p;
+
+  // check u64 overflow
+  size_t max_digits = max_digits_u64(base);
+  if (digit_count > max_digits) {
+    answer.ec = std::errc::result_out_of_range;
+    return answer;
+  }
+  // this check can be eliminated for all other types, but they will all require
+  // a max_digits(base) equivalent
+  if (digit_count == max_digits && i < min_safe_u64(base)) {
+    answer.ec = std::errc::result_out_of_range;
+    return answer;
+  }
+
+  // check other types overflow
+  if (!std::is_same<T, uint64_t>::value) {
+    if (i > uint64_t(std::numeric_limits<T>::max()) + uint64_t(negative)) {
+      answer.ec = std::errc::result_out_of_range;
+      return answer;
+    }
+  }
+
+  if (negative) {
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#pragma warning(push)
+#pragma warning(disable : 4146)
+#endif
+    // this weird workaround is required because:
+    // - converting unsigned to signed when its value is greater than signed max
+    // is UB pre-C++23.
+    // - reinterpret_casting (~i + 1) would work, but it is not constexpr
+    // this is always optimized into a neg instruction (note: T is an integer
+    // type)
+    value = T(-std::numeric_limits<T>::max() -
+              T(i - uint64_t(std::numeric_limits<T>::max())));
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#pragma warning(pop)
+#endif
+  } else {
+    value = T(i);
+  }
+
+  answer.ec = std::errc();
+  return answer;
+}
+
+} // namespace fast_float
+
+#endif
+
+#ifndef FASTFLOAT_FAST_TABLE_H
+#define FASTFLOAT_FAST_TABLE_H
+
+#include <cstdint>
+
+namespace fast_float {
+
+/**
+ * When mapping numbers from decimal to binary,
+ * we go from w * 10^q to m * 2^p but we have
+ * 10^q = 5^q * 2^q, so effectively
+ * we are trying to match
+ * w * 2^q * 5^q to m * 2^p. Thus the powers of two
+ * are not a concern since they can be represented
+ * exactly using the binary notation, only the powers of five
+ * affect the binary significand.
+ */
+
+/**
+ * The smallest non-zero float (binary64) is 2^-1074.
+ * We take as input numbers of the form w x 10^q where w < 2^64.
+ * We have that w * 10^-343  <  2^(64-344) 5^-343 < 2^-1076.
+ * However, we have that
+ * (2^64-1) * 10^-342 =  (2^64-1) * 2^-342 * 5^-342 > 2^-1074.
+ * Thus it is possible for a number of the form w * 10^-342 where
+ * w is a 64-bit value to be a non-zero floating-point number.
+ *********
+ * Any number of form w * 10^309 where w>= 1 is going to be
+ * infinite in binary64 so we never need to worry about powers
+ * of 5 greater than 308.
+ */
+template <class unused = void> struct powers_template {
+
+  constexpr static int smallest_power_of_five =
+      binary_format<double>::smallest_power_of_ten();
+  constexpr static int largest_power_of_five =
+      binary_format<double>::largest_power_of_ten();
+  constexpr static int number_of_entries =
+      2 * (largest_power_of_five - smallest_power_of_five + 1);
+  // Powers of five from 5^-342 all the way to 5^308 rounded toward one.
+  constexpr static uint64_t power_of_five_128[number_of_entries] = {
+      0xeef453d6923bd65a, 0x113faa2906a13b3f,
+      0x9558b4661b6565f8, 0x4ac7ca59a424c507,
+      0xbaaee17fa23ebf76, 0x5d79bcf00d2df649,
+      0xe95a99df8ace6f53, 0xf4d82c2c107973dc,
+      0x91d8a02bb6c10594, 0x79071b9b8a4be869,
+      0xb64ec836a47146f9, 0x9748e2826cdee284,
+      0xe3e27a444d8d98b7, 0xfd1b1b2308169b25,
+      0x8e6d8c6ab0787f72, 0xfe30f0f5e50e20f7,
+      0xb208ef855c969f4f, 0xbdbd2d335e51a935,
+      0xde8b2b66b3bc4723, 0xad2c788035e61382,
+      0x8b16fb203055ac76, 0x4c3bcb5021afcc31,
+      0xaddcb9e83c6b1793, 0xdf4abe242a1bbf3d,
+      0xd953e8624b85dd78, 0xd71d6dad34a2af0d,
+      0x87d4713d6f33aa6b, 0x8672648c40e5ad68,
+      0xa9c98d8ccb009506, 0x680efdaf511f18c2,
+      0xd43bf0effdc0ba48, 0x212bd1b2566def2,
+      0x84a57695fe98746d, 0x14bb630f7604b57,
+      0xa5ced43b7e3e9188, 0x419ea3bd35385e2d,
+      0xcf42894a5dce35ea, 0x52064cac828675b9,
+      0x818995ce7aa0e1b2, 0x7343efebd1940993,
+      0xa1ebfb4219491a1f, 0x1014ebe6c5f90bf8,
+      0xca66fa129f9b60a6, 0xd41a26e077774ef6,
+      0xfd00b897478238d0, 0x8920b098955522b4,
+      0x9e20735e8cb16382, 0x55b46e5f5d5535b0,
+      0xc5a890362fddbc62, 0xeb2189f734aa831d,
+      0xf712b443bbd52b7b, 0xa5e9ec7501d523e4,
+      0x9a6bb0aa55653b2d, 0x47b233c92125366e,
+      0xc1069cd4eabe89f8, 0x999ec0bb696e840a,
+      0xf148440a256e2c76, 0xc00670ea43ca250d,
+      0x96cd2a865764dbca, 0x380406926a5e5728,
+      0xbc807527ed3e12bc, 0xc605083704f5ecf2,
+      0xeba09271e88d976b, 0xf7864a44c633682e,
+      0x93445b8731587ea3, 0x7ab3ee6afbe0211d,
+      0xb8157268fdae9e4c, 0x5960ea05bad82964,
+      0xe61acf033d1a45df, 0x6fb92487298e33bd,
+      0x8fd0c16206306bab, 0xa5d3b6d479f8e056,
+      0xb3c4f1ba87bc8696, 0x8f48a4899877186c,
+      0xe0b62e2929aba83c, 0x331acdabfe94de87,
+      0x8c71dcd9ba0b4925, 0x9ff0c08b7f1d0b14,
+      0xaf8e5410288e1b6f, 0x7ecf0ae5ee44dd9,
+      0xdb71e91432b1a24a, 0xc9e82cd9f69d6150,
+      0x892731ac9faf056e, 0xbe311c083a225cd2,
+      0xab70fe17c79ac6ca, 0x6dbd630a48aaf406,
+      0xd64d3d9db981787d, 0x92cbbccdad5b108,
+      0x85f0468293f0eb4e, 0x25bbf56008c58ea5,
+      0xa76c582338ed2621, 0xaf2af2b80af6f24e,
+      0xd1476e2c07286faa, 0x1af5af660db4aee1,
+      0x82cca4db847945ca, 0x50d98d9fc890ed4d,
+      0xa37fce126597973c, 0xe50ff107bab528a0,
+      0xcc5fc196fefd7d0c, 0x1e53ed49a96272c8,
+      0xff77b1fcbebcdc4f, 0x25e8e89c13bb0f7a,
+      0x9faacf3df73609b1, 0x77b191618c54e9ac,
+      0xc795830d75038c1d, 0xd59df5b9ef6a2417,
+      0xf97ae3d0d2446f25, 0x4b0573286b44ad1d,
+      0x9becce62836ac577, 0x4ee367f9430aec32,
+      0xc2e801fb244576d5, 0x229c41f793cda73f,
+      0xf3a20279ed56d48a, 0x6b43527578c1110f,
+      0x9845418c345644d6, 0x830a13896b78aaa9,
+      0xbe5691ef416bd60c, 0x23cc986bc656d553,
+      0xedec366b11c6cb8f, 0x2cbfbe86b7ec8aa8,
+      0x94b3a202eb1c3f39, 0x7bf7d71432f3d6a9,
+      0xb9e08a83a5e34f07, 0xdaf5ccd93fb0cc53,
+      0xe858ad248f5c22c9, 0xd1b3400f8f9cff68,
+      0x91376c36d99995be, 0x23100809b9c21fa1,
+      0xb58547448ffffb2d, 0xabd40a0c2832a78a,
+      0xe2e69915b3fff9f9, 0x16c90c8f323f516c,
+      0x8dd01fad907ffc3b, 0xae3da7d97f6792e3,
+      0xb1442798f49ffb4a, 0x99cd11cfdf41779c,
+      0xdd95317f31c7fa1d, 0x40405643d711d583,
+      0x8a7d3eef7f1cfc52, 0x482835ea666b2572,
+      0xad1c8eab5ee43b66, 0xda3243650005eecf,
+      0xd863b256369d4a40, 0x90bed43e40076a82,
+      0x873e4f75e2224e68, 0x5a7744a6e804a291,
+      0xa90de3535aaae202, 0x711515d0a205cb36,
+      0xd3515c2831559a83, 0xd5a5b44ca873e03,
+      0x8412d9991ed58091, 0xe858790afe9486c2,
+      0xa5178fff668ae0b6, 0x626e974dbe39a872,
+      0xce5d73ff402d98e3, 0xfb0a3d212dc8128f,
+      0x80fa687f881c7f8e, 0x7ce66634bc9d0b99,
+      0xa139029f6a239f72, 0x1c1fffc1ebc44e80,
+      0xc987434744ac874e, 0xa327ffb266b56220,
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+      0x8000000000000000, 0x0,
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+      0xb5e620f480000000, 0x0,
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+      0x813f3978f8940984, 0x4000000000000000,
+      0xa18f07d736b90be5, 0x5000000000000000,
+      0xc9f2c9cd04674ede, 0xa400000000000000,
+      0xfc6f7c4045812296, 0x4d00000000000000,
+      0x9dc5ada82b70b59d, 0xf020000000000000,
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+      0xf684df56c3e01bc6, 0xc732000000000000,
+      0x9a130b963a6c115c, 0x3c7f400000000000,
+      0xc097ce7bc90715b3, 0x4b9f100000000000,
+      0xf0bdc21abb48db20, 0x1e86d40000000000,
+      0x96769950b50d88f4, 0x1314448000000000,
+      0xbc143fa4e250eb31, 0x17d955a000000000,
+      0xeb194f8e1ae525fd, 0x5dcfab0800000000,
+      0x92efd1b8d0cf37be, 0x5aa1cae500000000,
+      0xb7abc627050305ad, 0xf14a3d9e40000000,
+      0xe596b7b0c643c719, 0x6d9ccd05d0000000,
+      0x8f7e32ce7bea5c6f, 0xe4820023a2000000,
+      0xb35dbf821ae4f38b, 0xdda2802c8a800000,
+      0xe0352f62a19e306e, 0xd50b2037ad200000,
+      0x8c213d9da502de45, 0x4526f422cc340000,
+      0xaf298d050e4395d6, 0x9670b12b7f410000,
+      0xdaf3f04651d47b4c, 0x3c0cdd765f114000,
+      0x88d8762bf324cd0f, 0xa5880a69fb6ac800,
+      0xab0e93b6efee0053, 0x8eea0d047a457a00,
+      0xd5d238a4abe98068, 0x72a4904598d6d880,
+      0x85a36366eb71f041, 0x47a6da2b7f864750,
+      0xa70c3c40a64e6c51, 0x999090b65f67d924,
+      0xd0cf4b50cfe20765, 0xfff4b4e3f741cf6d,
+      0x82818f1281ed449f, 0xbff8f10e7a8921a4,
+      0xa321f2d7226895c7, 0xaff72d52192b6a0d,
+      0xcbea6f8ceb02bb39, 0x9bf4f8a69f764490,
+      0xfee50b7025c36a08, 0x2f236d04753d5b4,
+      0x9f4f2726179a2245, 0x1d762422c946590,
+      0xc722f0ef9d80aad6, 0x424d3ad2b7b97ef5,
+      0xf8ebad2b84e0d58b, 0xd2e0898765a7deb2,
+      0x9b934c3b330c8577, 0x63cc55f49f88eb2f,
+      0xc2781f49ffcfa6d5, 0x3cbf6b71c76b25fb,
+      0xf316271c7fc3908a, 0x8bef464e3945ef7a,
+      0x97edd871cfda3a56, 0x97758bf0e3cbb5ac,
+      0xbde94e8e43d0c8ec, 0x3d52eeed1cbea317,
+      0xed63a231d4c4fb27, 0x4ca7aaa863ee4bdd,
+      0x945e455f24fb1cf8, 0x8fe8caa93e74ef6a,
+      0xb975d6b6ee39e436, 0xb3e2fd538e122b44,
+      0xe7d34c64a9c85d44, 0x60dbbca87196b616,
+      0x90e40fbeea1d3a4a, 0xbc8955e946fe31cd,
+      0xb51d13aea4a488dd, 0x6babab6398bdbe41,
+      0xe264589a4dcdab14, 0xc696963c7eed2dd1,
+      0x8d7eb76070a08aec, 0xfc1e1de5cf543ca2,
+      0xb0de65388cc8ada8, 0x3b25a55f43294bcb,
+      0xdd15fe86affad912, 0x49ef0eb713f39ebe,
+      0x8a2dbf142dfcc7ab, 0x6e3569326c784337,
+      0xacb92ed9397bf996, 0x49c2c37f07965404,
+      0xd7e77a8f87daf7fb, 0xdc33745ec97be906,
+      0x86f0ac99b4e8dafd, 0x69a028bb3ded71a3,
+      0xa8acd7c0222311bc, 0xc40832ea0d68ce0c,
+      0xd2d80db02aabd62b, 0xf50a3fa490c30190,
+      0x83c7088e1aab65db, 0x792667c6da79e0fa,
+      0xa4b8cab1a1563f52, 0x577001b891185938,
+      0xcde6fd5e09abcf26, 0xed4c0226b55e6f86,
+      0x80b05e5ac60b6178, 0x544f8158315b05b4,
+      0xa0dc75f1778e39d6, 0x696361ae3db1c721,
+      0xc913936dd571c84c, 0x3bc3a19cd1e38e9,
+      0xfb5878494ace3a5f, 0x4ab48a04065c723,
+      0x9d174b2dcec0e47b, 0x62eb0d64283f9c76,
+      0xc45d1df942711d9a, 0x3ba5d0bd324f8394,
+      0xf5746577930d6500, 0xca8f44ec7ee36479,
+      0x9968bf6abbe85f20, 0x7e998b13cf4e1ecb,
+      0xbfc2ef456ae276e8, 0x9e3fedd8c321a67e,
+      0xefb3ab16c59b14a2, 0xc5cfe94ef3ea101e,
+      0x95d04aee3b80ece5, 0xbba1f1d158724a12,
+      0xbb445da9ca61281f, 0x2a8a6e45ae8edc97,
+      0xea1575143cf97226, 0xf52d09d71a3293bd,
+      0x924d692ca61be758, 0x593c2626705f9c56,
+      0xb6e0c377cfa2e12e, 0x6f8b2fb00c77836c,
+      0xe498f455c38b997a, 0xb6dfb9c0f956447,
+      0x8edf98b59a373fec, 0x4724bd4189bd5eac,
+      0xb2977ee300c50fe7, 0x58edec91ec2cb657,
+      0xdf3d5e9bc0f653e1, 0x2f2967b66737e3ed,
+      0x8b865b215899f46c, 0xbd79e0d20082ee74,
+      0xae67f1e9aec07187, 0xecd8590680a3aa11,
+      0xda01ee641a708de9, 0xe80e6f4820cc9495,
+      0x884134fe908658b2, 0x3109058d147fdcdd,
+      0xaa51823e34a7eede, 0xbd4b46f0599fd415,
+      0xd4e5e2cdc1d1ea96, 0x6c9e18ac7007c91a,
+      0x850fadc09923329e, 0x3e2cf6bc604ddb0,
+      0xa6539930bf6bff45, 0x84db8346b786151c,
+      0xcfe87f7cef46ff16, 0xe612641865679a63,
+      0x81f14fae158c5f6e, 0x4fcb7e8f3f60c07e,
+      0xa26da3999aef7749, 0xe3be5e330f38f09d,
+      0xcb090c8001ab551c, 0x5cadf5bfd3072cc5,
+      0xfdcb4fa002162a63, 0x73d9732fc7c8f7f6,
+      0x9e9f11c4014dda7e, 0x2867e7fddcdd9afa,
+      0xc646d63501a1511d, 0xb281e1fd541501b8,
+      0xf7d88bc24209a565, 0x1f225a7ca91a4226,
+      0x9ae757596946075f, 0x3375788de9b06958,
+      0xc1a12d2fc3978937, 0x52d6b1641c83ae,
+      0xf209787bb47d6b84, 0xc0678c5dbd23a49a,
+      0x9745eb4d50ce6332, 0xf840b7ba963646e0,
+      0xbd176620a501fbff, 0xb650e5a93bc3d898,
+      0xec5d3fa8ce427aff, 0xa3e51f138ab4cebe,
+      0x93ba47c980e98cdf, 0xc66f336c36b10137,
+      0xb8a8d9bbe123f017, 0xb80b0047445d4184,
+      0xe6d3102ad96cec1d, 0xa60dc059157491e5,
+      0x9043ea1ac7e41392, 0x87c89837ad68db2f,
+      0xb454e4a179dd1877, 0x29babe4598c311fb,
+      0xe16a1dc9d8545e94, 0xf4296dd6fef3d67a,
+      0x8ce2529e2734bb1d, 0x1899e4a65f58660c,
+      0xb01ae745b101e9e4, 0x5ec05dcff72e7f8f,
+      0xdc21a1171d42645d, 0x76707543f4fa1f73,
+      0x899504ae72497eba, 0x6a06494a791c53a8,
+      0xabfa45da0edbde69, 0x487db9d17636892,
+      0xd6f8d7509292d603, 0x45a9d2845d3c42b6,
+      0x865b86925b9bc5c2, 0xb8a2392ba45a9b2,
+      0xa7f26836f282b732, 0x8e6cac7768d7141e,
+      0xd1ef0244af2364ff, 0x3207d795430cd926,
+      0x8335616aed761f1f, 0x7f44e6bd49e807b8,
+      0xa402b9c5a8d3a6e7, 0x5f16206c9c6209a6,
+      0xcd036837130890a1, 0x36dba887c37a8c0f,
+      0x802221226be55a64, 0xc2494954da2c9789,
+      0xa02aa96b06deb0fd, 0xf2db9baa10b7bd6c,
+      0xc83553c5c8965d3d, 0x6f92829494e5acc7,
+      0xfa42a8b73abbf48c, 0xcb772339ba1f17f9,
+      0x9c69a97284b578d7, 0xff2a760414536efb,
+      0xc38413cf25e2d70d, 0xfef5138519684aba,
+      0xf46518c2ef5b8cd1, 0x7eb258665fc25d69,
+      0x98bf2f79d5993802, 0xef2f773ffbd97a61,
+      0xbeeefb584aff8603, 0xaafb550ffacfd8fa,
+      0xeeaaba2e5dbf6784, 0x95ba2a53f983cf38,
+      0x952ab45cfa97a0b2, 0xdd945a747bf26183,
+      0xba756174393d88df, 0x94f971119aeef9e4,
+      0xe912b9d1478ceb17, 0x7a37cd5601aab85d,
+      0x91abb422ccb812ee, 0xac62e055c10ab33a,
+      0xb616a12b7fe617aa, 0x577b986b314d6009,
+      0xe39c49765fdf9d94, 0xed5a7e85fda0b80b,
+      0x8e41ade9fbebc27d, 0x14588f13be847307,
+      0xb1d219647ae6b31c, 0x596eb2d8ae258fc8,
+      0xde469fbd99a05fe3, 0x6fca5f8ed9aef3bb,
+      0x8aec23d680043bee, 0x25de7bb9480d5854,
+      0xada72ccc20054ae9, 0xaf561aa79a10ae6a,
+      0xd910f7ff28069da4, 0x1b2ba1518094da04,
+      0x87aa9aff79042286, 0x90fb44d2f05d0842,
+      0xa99541bf57452b28, 0x353a1607ac744a53,
+      0xd3fa922f2d1675f2, 0x42889b8997915ce8,
+      0x847c9b5d7c2e09b7, 0x69956135febada11,
+      0xa59bc234db398c25, 0x43fab9837e699095,
+      0xcf02b2c21207ef2e, 0x94f967e45e03f4bb,
+      0x8161afb94b44f57d, 0x1d1be0eebac278f5,
+      0xa1ba1ba79e1632dc, 0x6462d92a69731732,
+      0xca28a291859bbf93, 0x7d7b8f7503cfdcfe,
+      0xfcb2cb35e702af78, 0x5cda735244c3d43e,
+      0x9defbf01b061adab, 0x3a0888136afa64a7,
+      0xc56baec21c7a1916, 0x88aaa1845b8fdd0,
+      0xf6c69a72a3989f5b, 0x8aad549e57273d45,
+      0x9a3c2087a63f6399, 0x36ac54e2f678864b,
+      0xc0cb28a98fcf3c7f, 0x84576a1bb416a7dd,
+      0xf0fdf2d3f3c30b9f, 0x656d44a2a11c51d5,
+      0x969eb7c47859e743, 0x9f644ae5a4b1b325,
+      0xbc4665b596706114, 0x873d5d9f0dde1fee,
+      0xeb57ff22fc0c7959, 0xa90cb506d155a7ea,
+      0x9316ff75dd87cbd8, 0x9a7f12442d588f2,
+      0xb7dcbf5354e9bece, 0xc11ed6d538aeb2f,
+      0xe5d3ef282a242e81, 0x8f1668c8a86da5fa,
+      0x8fa475791a569d10, 0xf96e017d694487bc,
+      0xb38d92d760ec4455, 0x37c981dcc395a9ac,
+      0xe070f78d3927556a, 0x85bbe253f47b1417,
+      0x8c469ab843b89562, 0x93956d7478ccec8e,
+      0xaf58416654a6babb, 0x387ac8d1970027b2,
+      0xdb2e51bfe9d0696a, 0x6997b05fcc0319e,
+      0x88fcf317f22241e2, 0x441fece3bdf81f03,
+      0xab3c2fddeeaad25a, 0xd527e81cad7626c3,
+      0xd60b3bd56a5586f1, 0x8a71e223d8d3b074,
+      0x85c7056562757456, 0xf6872d5667844e49,
+      0xa738c6bebb12d16c, 0xb428f8ac016561db,
+      0xd106f86e69d785c7, 0xe13336d701beba52,
+      0x82a45b450226b39c, 0xecc0024661173473,
+      0xa34d721642b06084, 0x27f002d7f95d0190,
+      0xcc20ce9bd35c78a5, 0x31ec038df7b441f4,
+      0xff290242c83396ce, 0x7e67047175a15271,
+      0x9f79a169bd203e41, 0xf0062c6e984d386,
+      0xc75809c42c684dd1, 0x52c07b78a3e60868,
+      0xf92e0c3537826145, 0xa7709a56ccdf8a82,
+      0x9bbcc7a142b17ccb, 0x88a66076400bb691,
+      0xc2abf989935ddbfe, 0x6acff893d00ea435,
+      0xf356f7ebf83552fe, 0x583f6b8c4124d43,
+      0x98165af37b2153de, 0xc3727a337a8b704a,
+      0xbe1bf1b059e9a8d6, 0x744f18c0592e4c5c,
+      0xeda2ee1c7064130c, 0x1162def06f79df73,
+      0x9485d4d1c63e8be7, 0x8addcb5645ac2ba8,
+      0xb9a74a0637ce2ee1, 0x6d953e2bd7173692,
+      0xe8111c87c5c1ba99, 0xc8fa8db6ccdd0437,
+      0x910ab1d4db9914a0, 0x1d9c9892400a22a2,
+      0xb54d5e4a127f59c8, 0x2503beb6d00cab4b,
+      0xe2a0b5dc971f303a, 0x2e44ae64840fd61d,
+      0x8da471a9de737e24, 0x5ceaecfed289e5d2,
+      0xb10d8e1456105dad, 0x7425a83e872c5f47,
+      0xdd50f1996b947518, 0xd12f124e28f77719,
+      0x8a5296ffe33cc92f, 0x82bd6b70d99aaa6f,
+      0xace73cbfdc0bfb7b, 0x636cc64d1001550b,
+      0xd8210befd30efa5a, 0x3c47f7e05401aa4e,
+      0x8714a775e3e95c78, 0x65acfaec34810a71,
+      0xa8d9d1535ce3b396, 0x7f1839a741a14d0d,
+      0xd31045a8341ca07c, 0x1ede48111209a050,
+      0x83ea2b892091e44d, 0x934aed0aab460432,
+      0xa4e4b66b68b65d60, 0xf81da84d5617853f,
+      0xce1de40642e3f4b9, 0x36251260ab9d668e,
+      0x80d2ae83e9ce78f3, 0xc1d72b7c6b426019,
+      0xa1075a24e4421730, 0xb24cf65b8612f81f,
+      0xc94930ae1d529cfc, 0xdee033f26797b627,
+      0xfb9b7cd9a4a7443c, 0x169840ef017da3b1,
+      0x9d412e0806e88aa5, 0x8e1f289560ee864e,
+      0xc491798a08a2ad4e, 0xf1a6f2bab92a27e2,
+      0xf5b5d7ec8acb58a2, 0xae10af696774b1db,
+      0x9991a6f3d6bf1765, 0xacca6da1e0a8ef29,
+      0xbff610b0cc6edd3f, 0x17fd090a58d32af3,
+      0xeff394dcff8a948e, 0xddfc4b4cef07f5b0,
+      0x95f83d0a1fb69cd9, 0x4abdaf101564f98e,
+      0xbb764c4ca7a4440f, 0x9d6d1ad41abe37f1,
+      0xea53df5fd18d5513, 0x84c86189216dc5ed,
+      0x92746b9be2f8552c, 0x32fd3cf5b4e49bb4,
+      0xb7118682dbb66a77, 0x3fbc8c33221dc2a1,
+      0xe4d5e82392a40515, 0xfabaf3feaa5334a,
+      0x8f05b1163ba6832d, 0x29cb4d87f2a7400e,
+      0xb2c71d5bca9023f8, 0x743e20e9ef511012,
+      0xdf78e4b2bd342cf6, 0x914da9246b255416,
+      0x8bab8eefb6409c1a, 0x1ad089b6c2f7548e,
+      0xae9672aba3d0c320, 0xa184ac2473b529b1,
+      0xda3c0f568cc4f3e8, 0xc9e5d72d90a2741e,
+      0x8865899617fb1871, 0x7e2fa67c7a658892,
+      0xaa7eebfb9df9de8d, 0xddbb901b98feeab7,
+      0xd51ea6fa85785631, 0x552a74227f3ea565,
+      0x8533285c936b35de, 0xd53a88958f87275f,
+      0xa67ff273b8460356, 0x8a892abaf368f137,
+      0xd01fef10a657842c, 0x2d2b7569b0432d85,
+      0x8213f56a67f6b29b, 0x9c3b29620e29fc73,
+      0xa298f2c501f45f42, 0x8349f3ba91b47b8f,
+      0xcb3f2f7642717713, 0x241c70a936219a73,
+      0xfe0efb53d30dd4d7, 0xed238cd383aa0110,
+      0x9ec95d1463e8a506, 0xf4363804324a40aa,
+      0xc67bb4597ce2ce48, 0xb143c6053edcd0d5,
+      0xf81aa16fdc1b81da, 0xdd94b7868e94050a,
+      0x9b10a4e5e9913128, 0xca7cf2b4191c8326,
+      0xc1d4ce1f63f57d72, 0xfd1c2f611f63a3f0,
+      0xf24a01a73cf2dccf, 0xbc633b39673c8cec,
+      0x976e41088617ca01, 0xd5be0503e085d813,
+      0xbd49d14aa79dbc82, 0x4b2d8644d8a74e18,
+      0xec9c459d51852ba2, 0xddf8e7d60ed1219e,
+      0x93e1ab8252f33b45, 0xcabb90e5c942b503,
+      0xb8da1662e7b00a17, 0x3d6a751f3b936243,
+      0xe7109bfba19c0c9d, 0xcc512670a783ad4,
+      0x906a617d450187e2, 0x27fb2b80668b24c5,
+      0xb484f9dc9641e9da, 0xb1f9f660802dedf6,
+      0xe1a63853bbd26451, 0x5e7873f8a0396973,
+      0x8d07e33455637eb2, 0xdb0b487b6423e1e8,
+      0xb049dc016abc5e5f, 0x91ce1a9a3d2cda62,
+      0xdc5c5301c56b75f7, 0x7641a140cc7810fb,
+      0x89b9b3e11b6329ba, 0xa9e904c87fcb0a9d,
+      0xac2820d9623bf429, 0x546345fa9fbdcd44,
+      0xd732290fbacaf133, 0xa97c177947ad4095,
+      0x867f59a9d4bed6c0, 0x49ed8eabcccc485d,
+      0xa81f301449ee8c70, 0x5c68f256bfff5a74,
+      0xd226fc195c6a2f8c, 0x73832eec6fff3111,
+      0x83585d8fd9c25db7, 0xc831fd53c5ff7eab,
+      0xa42e74f3d032f525, 0xba3e7ca8b77f5e55,
+      0xcd3a1230c43fb26f, 0x28ce1bd2e55f35eb,
+      0x80444b5e7aa7cf85, 0x7980d163cf5b81b3,
+      0xa0555e361951c366, 0xd7e105bcc332621f,
+      0xc86ab5c39fa63440, 0x8dd9472bf3fefaa7,
+      0xfa856334878fc150, 0xb14f98f6f0feb951,
+      0x9c935e00d4b9d8d2, 0x6ed1bf9a569f33d3,
+      0xc3b8358109e84f07, 0xa862f80ec4700c8,
+      0xf4a642e14c6262c8, 0xcd27bb612758c0fa,
+      0x98e7e9cccfbd7dbd, 0x8038d51cb897789c,
+      0xbf21e44003acdd2c, 0xe0470a63e6bd56c3,
+      0xeeea5d5004981478, 0x1858ccfce06cac74,
+      0x95527a5202df0ccb, 0xf37801e0c43ebc8,
+      0xbaa718e68396cffd, 0xd30560258f54e6ba,
+      0xe950df20247c83fd, 0x47c6b82ef32a2069,
+      0x91d28b7416cdd27e, 0x4cdc331d57fa5441,
+      0xb6472e511c81471d, 0xe0133fe4adf8e952,
+      0xe3d8f9e563a198e5, 0x58180fddd97723a6,
+      0x8e679c2f5e44ff8f, 0x570f09eaa7ea7648,
+  };
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <class unused>
+constexpr uint64_t
+    powers_template<unused>::power_of_five_128[number_of_entries];
+
+#endif
+
+using powers = powers_template<>;
+
+} // namespace fast_float
+
+#endif
+
+#ifndef FASTFLOAT_DECIMAL_TO_BINARY_H
+#define FASTFLOAT_DECIMAL_TO_BINARY_H
+
+#include <cfloat>
+#include <cinttypes>
+#include <cmath>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+
+namespace fast_float {
+
+// This will compute or rather approximate w * 5**q and return a pair of 64-bit
+// words approximating the result, with the "high" part corresponding to the
+// most significant bits and the low part corresponding to the least significant
+// bits.
+//
+template <int bit_precision>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 value128
+compute_product_approximation(int64_t q, uint64_t w) {
+  const int index = 2 * int(q - powers::smallest_power_of_five);
+  // For small values of q, e.g., q in [0,27], the answer is always exact
+  // because The line value128 firstproduct = full_multiplication(w,
+  // power_of_five_128[index]); gives the exact answer.
+  value128 firstproduct =
+      full_multiplication(w, powers::power_of_five_128[index]);
+  static_assert((bit_precision >= 0) && (bit_precision <= 64),
+                " precision should  be in (0,64]");
+  constexpr uint64_t precision_mask =
+      (bit_precision < 64) ? (uint64_t(0xFFFFFFFFFFFFFFFF) >> bit_precision)
+                           : uint64_t(0xFFFFFFFFFFFFFFFF);
+  if ((firstproduct.high & precision_mask) ==
+      precision_mask) { // could further guard with  (lower + w < lower)
+    // regarding the second product, we only need secondproduct.high, but our
+    // expectation is that the compiler will optimize this extra work away if
+    // needed.
+    value128 secondproduct =
+        full_multiplication(w, powers::power_of_five_128[index + 1]);
+    firstproduct.low += secondproduct.high;
+    if (secondproduct.high > firstproduct.low) {
+      firstproduct.high++;
+    }
+  }
+  return firstproduct;
+}
+
+namespace detail {
+/**
+ * For q in (0,350), we have that
+ *  f = (((152170 + 65536) * q ) >> 16);
+ * is equal to
+ *   floor(p) + q
+ * where
+ *   p = log(5**q)/log(2) = q * log(5)/log(2)
+ *
+ * For negative values of q in (-400,0), we have that
+ *  f = (((152170 + 65536) * q ) >> 16);
+ * is equal to
+ *   -ceil(p) + q
+ * where
+ *   p = log(5**-q)/log(2) = -q * log(5)/log(2)
+ */
+constexpr fastfloat_really_inline int32_t power(int32_t q) noexcept {
+  return (((152170 + 65536) * q) >> 16) + 63;
+}
+} // namespace detail
+
+// create an adjusted mantissa, biased by the invalid power2
+// for significant digits already multiplied by 10 ** q.
+template <typename binary>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 adjusted_mantissa
+compute_error_scaled(int64_t q, uint64_t w, int lz) noexcept {
+  int hilz = int(w >> 63) ^ 1;
+  adjusted_mantissa answer;
+  answer.mantissa = w << hilz;
+  int bias = binary::mantissa_explicit_bits() - binary::minimum_exponent();
+  answer.power2 = int32_t(detail::power(int32_t(q)) + bias - hilz - lz - 62 +
+                          invalid_am_bias);
+  return answer;
+}
+
+// w * 10 ** q, without rounding the representation up.
+// the power2 in the exponent will be adjusted by invalid_am_bias.
+template <typename binary>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+compute_error(int64_t q, uint64_t w) noexcept {
+  int lz = leading_zeroes(w);
+  w <<= lz;
+  value128 product =
+      compute_product_approximation<binary::mantissa_explicit_bits() + 3>(q, w);
+  return compute_error_scaled<binary>(q, product.high, lz);
+}
+
+// w * 10 ** q
+// The returned value should be a valid ieee64 number that simply need to be
+// packed. However, in some very rare cases, the computation will fail. In such
+// cases, we return an adjusted_mantissa with a negative power of 2: the caller
+// should recompute in such cases.
+template <typename binary>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+compute_float(int64_t q, uint64_t w) noexcept {
+  adjusted_mantissa answer;
+  if ((w == 0) || (q < binary::smallest_power_of_ten())) {
+    answer.power2 = 0;
+    answer.mantissa = 0;
+    // result should be zero
+    return answer;
+  }
+  if (q > binary::largest_power_of_ten()) {
+    // we want to get infinity:
+    answer.power2 = binary::infinite_power();
+    answer.mantissa = 0;
+    return answer;
+  }
+  // At this point in time q is in [powers::smallest_power_of_five,
+  // powers::largest_power_of_five].
+
+  // We want the most significant bit of i to be 1. Shift if needed.
+  int lz = leading_zeroes(w);
+  w <<= lz;
+
+  // The required precision is binary::mantissa_explicit_bits() + 3 because
+  // 1. We need the implicit bit
+  // 2. We need an extra bit for rounding purposes
+  // 3. We might lose a bit due to the "upperbit" routine (result too small,
+  // requiring a shift)
+
+  value128 product =
+      compute_product_approximation<binary::mantissa_explicit_bits() + 3>(q, w);
+  // The computed 'product' is always sufficient.
+  // Mathematical proof:
+  // Noble Mushtak and Daniel Lemire, Fast Number Parsing Without Fallback (to
+  // appear) See script/mushtak_lemire.py
+
+  // The "compute_product_approximation" function can be slightly slower than a
+  // branchless approach: value128 product = compute_product(q, w); but in
+  // practice, we can win big with the compute_product_approximation if its
+  // additional branch is easily predicted. Which is best is data specific.
+  int upperbit = int(product.high >> 63);
+  int shift = upperbit + 64 - binary::mantissa_explicit_bits() - 3;
+
+  answer.mantissa = product.high >> shift;
+
+  answer.power2 = int32_t(detail::power(int32_t(q)) + upperbit - lz -
+                          binary::minimum_exponent());
+  if (answer.power2 <= 0) { // we have a subnormal?
+    // Here have that answer.power2 <= 0 so -answer.power2 >= 0
+    if (-answer.power2 + 1 >=
+        64) { // if we have more than 64 bits below the minimum exponent, you
+              // have a zero for sure.
+      answer.power2 = 0;
+      answer.mantissa = 0;
+      // result should be zero
+      return answer;
+    }
+    // next line is safe because -answer.power2 + 1 < 64
+    answer.mantissa >>= -answer.power2 + 1;
+    // Thankfully, we can't have both "round-to-even" and subnormals because
+    // "round-to-even" only occurs for powers close to 0.
+    answer.mantissa += (answer.mantissa & 1); // round up
+    answer.mantissa >>= 1;
+    // There is a weird scenario where we don't have a subnormal but just.
+    // Suppose we start with 2.2250738585072013e-308, we end up
+    // with 0x3fffffffffffff x 2^-1023-53 which is technically subnormal
+    // whereas 0x40000000000000 x 2^-1023-53  is normal. Now, we need to round
+    // up 0x3fffffffffffff x 2^-1023-53  and once we do, we are no longer
+    // subnormal, but we can only know this after rounding.
+    // So we only declare a subnormal if we are smaller than the threshold.
+    answer.power2 =
+        (answer.mantissa < (uint64_t(1) << binary::mantissa_explicit_bits()))
+            ? 0
+            : 1;
+    return answer;
+  }
+
+  // usually, we round *up*, but if we fall right in between and and we have an
+  // even basis, we need to round down
+  // We are only concerned with the cases where 5**q fits in single 64-bit word.
+  if ((product.low <= 1) && (q >= binary::min_exponent_round_to_even()) &&
+      (q <= binary::max_exponent_round_to_even()) &&
+      ((answer.mantissa & 3) == 1)) { // we may fall between two floats!
+    // To be in-between two floats we need that in doing
+    //   answer.mantissa = product.high >> (upperbit + 64 -
+    //   binary::mantissa_explicit_bits() - 3);
+    // ... we dropped out only zeroes. But if this happened, then we can go
+    // back!!!
+    if ((answer.mantissa << shift) == product.high) {
+      answer.mantissa &= ~uint64_t(1); // flip it so that we do not round up
+    }
+  }
+
+  answer.mantissa += (answer.mantissa & 1); // round up
+  answer.mantissa >>= 1;
+  if (answer.mantissa >= (uint64_t(2) << binary::mantissa_explicit_bits())) {
+    answer.mantissa = (uint64_t(1) << binary::mantissa_explicit_bits());
+    answer.power2++; // undo previous addition
+  }
+
+  answer.mantissa &= ~(uint64_t(1) << binary::mantissa_explicit_bits());
+  if (answer.power2 >= binary::infinite_power()) { // infinity
+    answer.power2 = binary::infinite_power();
+    answer.mantissa = 0;
+  }
+  return answer;
+}
+
+} // namespace fast_float
+
+#endif
+
+#ifndef FASTFLOAT_BIGINT_H
+#define FASTFLOAT_BIGINT_H
+
+#include <algorithm>
+#include <cstdint>
+#include <climits>
+#include <cstring>
+
+
+namespace fast_float {
+
+// the limb width: we want efficient multiplication of double the bits in
+// limb, or for 64-bit limbs, at least 64-bit multiplication where we can
+// extract the high and low parts efficiently. this is every 64-bit
+// architecture except for sparc, which emulates 128-bit multiplication.
+// we might have platforms where `CHAR_BIT` is not 8, so let's avoid
+// doing `8 * sizeof(limb)`.
+#if defined(FASTFLOAT_64BIT) && !defined(__sparc)
+#define FASTFLOAT_64BIT_LIMB 1
+typedef uint64_t limb;
+constexpr size_t limb_bits = 64;
+#else
+#define FASTFLOAT_32BIT_LIMB
+typedef uint32_t limb;
+constexpr size_t limb_bits = 32;
+#endif
+
+typedef span<limb> limb_span;
+
+// number of bits in a bigint. this needs to be at least the number
+// of bits required to store the largest bigint, which is
+// `log2(10**(digits + max_exp))`, or `log2(10**(767 + 342))`, or
+// ~3600 bits, so we round to 4000.
+constexpr size_t bigint_bits = 4000;
+constexpr size_t bigint_limbs = bigint_bits / limb_bits;
+
+// vector-like type that is allocated on the stack. the entire
+// buffer is pre-allocated, and only the length changes.
+template <uint16_t size> struct stackvec {
+  limb data[size];
+  // we never need more than 150 limbs
+  uint16_t length{0};
+
+  stackvec() = default;
+  stackvec(const stackvec &) = delete;
+  stackvec &operator=(const stackvec &) = delete;
+  stackvec(stackvec &&) = delete;
+  stackvec &operator=(stackvec &&other) = delete;
+
+  // create stack vector from existing limb span.
+  FASTFLOAT_CONSTEXPR20 stackvec(limb_span s) {
+    FASTFLOAT_ASSERT(try_extend(s));
+  }
+
+  FASTFLOAT_CONSTEXPR14 limb &operator[](size_t index) noexcept {
+    FASTFLOAT_DEBUG_ASSERT(index < length);
+    return data[index];
+  }
+  FASTFLOAT_CONSTEXPR14 const limb &operator[](size_t index) const noexcept {
+    FASTFLOAT_DEBUG_ASSERT(index < length);
+    return data[index];
+  }
+  // index from the end of the container
+  FASTFLOAT_CONSTEXPR14 const limb &rindex(size_t index) const noexcept {
+    FASTFLOAT_DEBUG_ASSERT(index < length);
+    size_t rindex = length - index - 1;
+    return data[rindex];
+  }
+
+  // set the length, without bounds checking.
+  FASTFLOAT_CONSTEXPR14 void set_len(size_t len) noexcept {
+    length = uint16_t(len);
+  }
+  constexpr size_t len() const noexcept { return length; }
+  constexpr bool is_empty() const noexcept { return length == 0; }
+  constexpr size_t capacity() const noexcept { return size; }
+  // append item to vector, without bounds checking
+  FASTFLOAT_CONSTEXPR14 void push_unchecked(limb value) noexcept {
+    data[length] = value;
+    length++;
+  }
+  // append item to vector, returning if item was added
+  FASTFLOAT_CONSTEXPR14 bool try_push(limb value) noexcept {
+    if (len() < capacity()) {
+      push_unchecked(value);
+      return true;
+    } else {
+      return false;
+    }
+  }
+  // add items to the vector, from a span, without bounds checking
+  FASTFLOAT_CONSTEXPR20 void extend_unchecked(limb_span s) noexcept {
+    limb *ptr = data + length;
+    std::copy_n(s.ptr, s.len(), ptr);
+    set_len(len() + s.len());
+  }
+  // try to add items to the vector, returning if items were added
+  FASTFLOAT_CONSTEXPR20 bool try_extend(limb_span s) noexcept {
+    if (len() + s.len() <= capacity()) {
+      extend_unchecked(s);
+      return true;
+    } else {
+      return false;
+    }
+  }
+  // resize the vector, without bounds checking
+  // if the new size is longer than the vector, assign value to each
+  // appended item.
+  FASTFLOAT_CONSTEXPR20
+  void resize_unchecked(size_t new_len, limb value) noexcept {
+    if (new_len > len()) {
+      size_t count = new_len - len();
+      limb *first = data + len();
+      limb *last = first + count;
+      ::std::fill(first, last, value);
+      set_len(new_len);
+    } else {
+      set_len(new_len);
+    }
+  }
+  // try to resize the vector, returning if the vector was resized.
+  FASTFLOAT_CONSTEXPR20 bool try_resize(size_t new_len, limb value) noexcept {
+    if (new_len > capacity()) {
+      return false;
+    } else {
+      resize_unchecked(new_len, value);
+      return true;
+    }
+  }
+  // check if any limbs are non-zero after the given index.
+  // this needs to be done in reverse order, since the index
+  // is relative to the most significant limbs.
+  FASTFLOAT_CONSTEXPR14 bool nonzero(size_t index) const noexcept {
+    while (index < len()) {
+      if (rindex(index) != 0) {
+        return true;
+      }
+      index++;
+    }
+    return false;
+  }
+  // normalize the big integer, so most-significant zero limbs are removed.
+  FASTFLOAT_CONSTEXPR14 void normalize() noexcept {
+    while (len() > 0 && rindex(0) == 0) {
+      length--;
+    }
+  }
+};
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 uint64_t
+empty_hi64(bool &truncated) noexcept {
+  truncated = false;
+  return 0;
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+uint64_hi64(uint64_t r0, bool &truncated) noexcept {
+  truncated = false;
+  int shl = leading_zeroes(r0);
+  return r0 << shl;
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+uint64_hi64(uint64_t r0, uint64_t r1, bool &truncated) noexcept {
+  int shl = leading_zeroes(r0);
+  if (shl == 0) {
+    truncated = r1 != 0;
+    return r0;
+  } else {
+    int shr = 64 - shl;
+    truncated = (r1 << shl) != 0;
+    return (r0 << shl) | (r1 >> shr);
+  }
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+uint32_hi64(uint32_t r0, bool &truncated) noexcept {
+  return uint64_hi64(r0, truncated);
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+uint32_hi64(uint32_t r0, uint32_t r1, bool &truncated) noexcept {
+  uint64_t x0 = r0;
+  uint64_t x1 = r1;
+  return uint64_hi64((x0 << 32) | x1, truncated);
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 uint64_t
+uint32_hi64(uint32_t r0, uint32_t r1, uint32_t r2, bool &truncated) noexcept {
+  uint64_t x0 = r0;
+  uint64_t x1 = r1;
+  uint64_t x2 = r2;
+  return uint64_hi64(x0, (x1 << 32) | x2, truncated);
+}
+
+// add two small integers, checking for overflow.
+// we want an efficient operation. for msvc, where
+// we don't have built-in intrinsics, this is still
+// pretty fast.
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 limb
+scalar_add(limb x, limb y, bool &overflow) noexcept {
+  limb z;
+// gcc and clang
+#if defined(__has_builtin)
+#if __has_builtin(__builtin_add_overflow)
+  if (!cpp20_and_in_constexpr()) {
+    overflow = __builtin_add_overflow(x, y, &z);
+    return z;
+  }
+#endif
+#endif
+
+  // generic, this still optimizes correctly on MSVC.
+  z = x + y;
+  overflow = z < x;
+  return z;
+}
+
+// multiply two small integers, getting both the high and low bits.
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 limb
+scalar_mul(limb x, limb y, limb &carry) noexcept {
+#ifdef FASTFLOAT_64BIT_LIMB
+#if defined(__SIZEOF_INT128__)
+  // GCC and clang both define it as an extension.
+  __uint128_t z = __uint128_t(x) * __uint128_t(y) + __uint128_t(carry);
+  carry = limb(z >> limb_bits);
+  return limb(z);
+#else
+  // fallback, no native 128-bit integer multiplication with carry.
+  // on msvc, this optimizes identically, somehow.
+  value128 z = full_multiplication(x, y);
+  bool overflow;
+  z.low = scalar_add(z.low, carry, overflow);
+  z.high += uint64_t(overflow); // cannot overflow
+  carry = z.high;
+  return z.low;
+#endif
+#else
+  uint64_t z = uint64_t(x) * uint64_t(y) + uint64_t(carry);
+  carry = limb(z >> limb_bits);
+  return limb(z);
+#endif
+}
+
+// add scalar value to bigint starting from offset.
+// used in grade school multiplication
+template <uint16_t size>
+inline FASTFLOAT_CONSTEXPR20 bool small_add_from(stackvec<size> &vec, limb y,
+                                                 size_t start) noexcept {
+  size_t index = start;
+  limb carry = y;
+  bool overflow;
+  while (carry != 0 && index < vec.len()) {
+    vec[index] = scalar_add(vec[index], carry, overflow);
+    carry = limb(overflow);
+    index += 1;
+  }
+  if (carry != 0) {
+    FASTFLOAT_TRY(vec.try_push(carry));
+  }
+  return true;
+}
+
+// add scalar value to bigint.
+template <uint16_t size>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 bool
+small_add(stackvec<size> &vec, limb y) noexcept {
+  return small_add_from(vec, y, 0);
+}
+
+// multiply bigint by scalar value.
+template <uint16_t size>
+inline FASTFLOAT_CONSTEXPR20 bool small_mul(stackvec<size> &vec,
+                                            limb y) noexcept {
+  limb carry = 0;
+  for (size_t index = 0; index < vec.len(); index++) {
+    vec[index] = scalar_mul(vec[index], y, carry);
+  }
+  if (carry != 0) {
+    FASTFLOAT_TRY(vec.try_push(carry));
+  }
+  return true;
+}
+
+// add bigint to bigint starting from index.
+// used in grade school multiplication
+template <uint16_t size>
+FASTFLOAT_CONSTEXPR20 bool large_add_from(stackvec<size> &x, limb_span y,
+                                          size_t start) noexcept {
+  // the effective x buffer is from `xstart..x.len()`, so exit early
+  // if we can't get that current range.
+  if (x.len() < start || y.len() > x.len() - start) {
+    FASTFLOAT_TRY(x.try_resize(y.len() + start, 0));
+  }
+
+  bool carry = false;
+  for (size_t index = 0; index < y.len(); index++) {
+    limb xi = x[index + start];
+    limb yi = y[index];
+    bool c1 = false;
+    bool c2 = false;
+    xi = scalar_add(xi, yi, c1);
+    if (carry) {
+      xi = scalar_add(xi, 1, c2);
+    }
+    x[index + start] = xi;
+    carry = c1 | c2;
+  }
+
+  // handle overflow
+  if (carry) {
+    FASTFLOAT_TRY(small_add_from(x, 1, y.len() + start));
+  }
+  return true;
+}
+
+// add bigint to bigint.
+template <uint16_t size>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 bool
+large_add_from(stackvec<size> &x, limb_span y) noexcept {
+  return large_add_from(x, y, 0);
+}
+
+// grade-school multiplication algorithm
+template <uint16_t size>
+FASTFLOAT_CONSTEXPR20 bool long_mul(stackvec<size> &x, limb_span y) noexcept {
+  limb_span xs = limb_span(x.data, x.len());
+  stackvec<size> z(xs);
+  limb_span zs = limb_span(z.data, z.len());
+
+  if (y.len() != 0) {
+    limb y0 = y[0];
+    FASTFLOAT_TRY(small_mul(x, y0));
+    for (size_t index = 1; index < y.len(); index++) {
+      limb yi = y[index];
+      stackvec<size> zi;
+      if (yi != 0) {
+        // re-use the same buffer throughout
+        zi.set_len(0);
+        FASTFLOAT_TRY(zi.try_extend(zs));
+        FASTFLOAT_TRY(small_mul(zi, yi));
+        limb_span zis = limb_span(zi.data, zi.len());
+        FASTFLOAT_TRY(large_add_from(x, zis, index));
+      }
+    }
+  }
+
+  x.normalize();
+  return true;
+}
+
+// grade-school multiplication algorithm
+template <uint16_t size>
+FASTFLOAT_CONSTEXPR20 bool large_mul(stackvec<size> &x, limb_span y) noexcept {
+  if (y.len() == 1) {
+    FASTFLOAT_TRY(small_mul(x, y[0]));
+  } else {
+    FASTFLOAT_TRY(long_mul(x, y));
+  }
+  return true;
+}
+
+template <typename = void> struct pow5_tables {
+  static constexpr uint32_t large_step = 135;
+  static constexpr uint64_t small_power_of_5[] = {
+      1UL,
+      5UL,
+      25UL,
+      125UL,
+      625UL,
+      3125UL,
+      15625UL,
+      78125UL,
+      390625UL,
+      1953125UL,
+      9765625UL,
+      48828125UL,
+      244140625UL,
+      1220703125UL,
+      6103515625UL,
+      30517578125UL,
+      152587890625UL,
+      762939453125UL,
+      3814697265625UL,
+      19073486328125UL,
+      95367431640625UL,
+      476837158203125UL,
+      2384185791015625UL,
+      11920928955078125UL,
+      59604644775390625UL,
+      298023223876953125UL,
+      1490116119384765625UL,
+      7450580596923828125UL,
+  };
+#ifdef FASTFLOAT_64BIT_LIMB
+  constexpr static limb large_power_of_5[] = {
+      1414648277510068013UL, 9180637584431281687UL, 4539964771860779200UL,
+      10482974169319127550UL, 198276706040285095UL};
+#else
+  constexpr static limb large_power_of_5[] = {
+      4279965485U, 329373468U,  4020270615U, 2137533757U, 4287402176U,
+      1057042919U, 1071430142U, 2440757623U, 381945767U,  46164893U};
+#endif
+};
+
+#if FASTFLOAT_DETAIL_MUST_DEFINE_CONSTEXPR_VARIABLE
+
+template <typename T> constexpr uint32_t pow5_tables<T>::large_step;
+
+template <typename T> constexpr uint64_t pow5_tables<T>::small_power_of_5[];
+
+template <typename T> constexpr limb pow5_tables<T>::large_power_of_5[];
+
+#endif
+
+// big integer type. implements a small subset of big integer
+// arithmetic, using simple algorithms since asymptotically
+// faster algorithms are slower for a small number of limbs.
+// all operations assume the big-integer is normalized.
+struct bigint : pow5_tables<> {
+  // storage of the limbs, in little-endian order.
+  stackvec<bigint_limbs> vec;
+
+  FASTFLOAT_CONSTEXPR20 bigint() : vec() {}
+  bigint(const bigint &) = delete;
+  bigint &operator=(const bigint &) = delete;
+  bigint(bigint &&) = delete;
+  bigint &operator=(bigint &&other) = delete;
+
+  FASTFLOAT_CONSTEXPR20 bigint(uint64_t value) : vec() {
+#ifdef FASTFLOAT_64BIT_LIMB
+    vec.push_unchecked(value);
+#else
+    vec.push_unchecked(uint32_t(value));
+    vec.push_unchecked(uint32_t(value >> 32));
+#endif
+    vec.normalize();
+  }
+
+  // get the high 64 bits from the vector, and if bits were truncated.
+  // this is to get the significant digits for the float.
+  FASTFLOAT_CONSTEXPR20 uint64_t hi64(bool &truncated) const noexcept {
+#ifdef FASTFLOAT_64BIT_LIMB
+    if (vec.len() == 0) {
+      return empty_hi64(truncated);
+    } else if (vec.len() == 1) {
+      return uint64_hi64(vec.rindex(0), truncated);
+    } else {
+      uint64_t result = uint64_hi64(vec.rindex(0), vec.rindex(1), truncated);
+      truncated |= vec.nonzero(2);
+      return result;
+    }
+#else
+    if (vec.len() == 0) {
+      return empty_hi64(truncated);
+    } else if (vec.len() == 1) {
+      return uint32_hi64(vec.rindex(0), truncated);
+    } else if (vec.len() == 2) {
+      return uint32_hi64(vec.rindex(0), vec.rindex(1), truncated);
+    } else {
+      uint64_t result =
+          uint32_hi64(vec.rindex(0), vec.rindex(1), vec.rindex(2), truncated);
+      truncated |= vec.nonzero(3);
+      return result;
+    }
+#endif
+  }
+
+  // compare two big integers, returning the large value.
+  // assumes both are normalized. if the return value is
+  // negative, other is larger, if the return value is
+  // positive, this is larger, otherwise they are equal.
+  // the limbs are stored in little-endian order, so we
+  // must compare the limbs in ever order.
+  FASTFLOAT_CONSTEXPR20 int compare(const bigint &other) const noexcept {
+    if (vec.len() > other.vec.len()) {
+      return 1;
+    } else if (vec.len() < other.vec.len()) {
+      return -1;
+    } else {
+      for (size_t index = vec.len(); index > 0; index--) {
+        limb xi = vec[index - 1];
+        limb yi = other.vec[index - 1];
+        if (xi > yi) {
+          return 1;
+        } else if (xi < yi) {
+          return -1;
+        }
+      }
+      return 0;
+    }
+  }
+
+  // shift left each limb n bits, carrying over to the new limb
+  // returns true if we were able to shift all the digits.
+  FASTFLOAT_CONSTEXPR20 bool shl_bits(size_t n) noexcept {
+    // Internally, for each item, we shift left by n, and add the previous
+    // right shifted limb-bits.
+    // For example, we transform (for u8) shifted left 2, to:
+    //      b10100100 b01000010
+    //      b10 b10010001 b00001000
+    FASTFLOAT_DEBUG_ASSERT(n != 0);
+    FASTFLOAT_DEBUG_ASSERT(n < sizeof(limb) * 8);
+
+    size_t shl = n;
+    size_t shr = limb_bits - shl;
+    limb prev = 0;
+    for (size_t index = 0; index < vec.len(); index++) {
+      limb xi = vec[index];
+      vec[index] = (xi << shl) | (prev >> shr);
+      prev = xi;
+    }
+
+    limb carry = prev >> shr;
+    if (carry != 0) {
+      return vec.try_push(carry);
+    }
+    return true;
+  }
+
+  // move the limbs left by `n` limbs.
+  FASTFLOAT_CONSTEXPR20 bool shl_limbs(size_t n) noexcept {
+    FASTFLOAT_DEBUG_ASSERT(n != 0);
+    if (n + vec.len() > vec.capacity()) {
+      return false;
+    } else if (!vec.is_empty()) {
+      // move limbs
+      limb *dst = vec.data + n;
+      const limb *src = vec.data;
+      std::copy_backward(src, src + vec.len(), dst + vec.len());
+      // fill in empty limbs
+      limb *first = vec.data;
+      limb *last = first + n;
+      ::std::fill(first, last, 0);
+      vec.set_len(n + vec.len());
+      return true;
+    } else {
+      return true;
+    }
+  }
+
+  // move the limbs left by `n` bits.
+  FASTFLOAT_CONSTEXPR20 bool shl(size_t n) noexcept {
+    size_t rem = n % limb_bits;
+    size_t div = n / limb_bits;
+    if (rem != 0) {
+      FASTFLOAT_TRY(shl_bits(rem));
+    }
+    if (div != 0) {
+      FASTFLOAT_TRY(shl_limbs(div));
+    }
+    return true;
+  }
+
+  // get the number of leading zeros in the bigint.
+  FASTFLOAT_CONSTEXPR20 int ctlz() const noexcept {
+    if (vec.is_empty()) {
+      return 0;
+    } else {
+#ifdef FASTFLOAT_64BIT_LIMB
+      return leading_zeroes(vec.rindex(0));
+#else
+      // no use defining a specialized leading_zeroes for a 32-bit type.
+      uint64_t r0 = vec.rindex(0);
+      return leading_zeroes(r0 << 32);
+#endif
+    }
+  }
+
+  // get the number of bits in the bigint.
+  FASTFLOAT_CONSTEXPR20 int bit_length() const noexcept {
+    int lz = ctlz();
+    return int(limb_bits * vec.len()) - lz;
+  }
+
+  FASTFLOAT_CONSTEXPR20 bool mul(limb y) noexcept { return small_mul(vec, y); }
+
+  FASTFLOAT_CONSTEXPR20 bool add(limb y) noexcept { return small_add(vec, y); }
+
+  // multiply as if by 2 raised to a power.
+  FASTFLOAT_CONSTEXPR20 bool pow2(uint32_t exp) noexcept { return shl(exp); }
+
+  // multiply as if by 5 raised to a power.
+  FASTFLOAT_CONSTEXPR20 bool pow5(uint32_t exp) noexcept {
+    // multiply by a power of 5
+    size_t large_length = sizeof(large_power_of_5) / sizeof(limb);
+    limb_span large = limb_span(large_power_of_5, large_length);
+    while (exp >= large_step) {
+      FASTFLOAT_TRY(large_mul(vec, large));
+      exp -= large_step;
+    }
+#ifdef FASTFLOAT_64BIT_LIMB
+    uint32_t small_step = 27;
+    limb max_native = 7450580596923828125UL;
+#else
+    uint32_t small_step = 13;
+    limb max_native = 1220703125U;
+#endif
+    while (exp >= small_step) {
+      FASTFLOAT_TRY(small_mul(vec, max_native));
+      exp -= small_step;
+    }
+    if (exp != 0) {
+      // Work around clang bug https://godbolt.org/z/zedh7rrhc
+      // This is similar to https://github.com/llvm/llvm-project/issues/47746,
+      // except the workaround described there don't work here
+      FASTFLOAT_TRY(small_mul(
+          vec, limb(((void)small_power_of_5[0], small_power_of_5[exp]))));
+    }
+
+    return true;
+  }
+
+  // multiply as if by 10 raised to a power.
+  FASTFLOAT_CONSTEXPR20 bool pow10(uint32_t exp) noexcept {
+    FASTFLOAT_TRY(pow5(exp));
+    return pow2(exp);
+  }
+};
+
+} // namespace fast_float
+
+#endif
+
+#ifndef FASTFLOAT_DIGIT_COMPARISON_H
+#define FASTFLOAT_DIGIT_COMPARISON_H
+
+#include <algorithm>
+#include <cstdint>
+#include <cstring>
+#include <iterator>
+
+
+namespace fast_float {
+
+// 1e0 to 1e19
+constexpr static uint64_t powers_of_ten_uint64[] = {1UL,
+                                                    10UL,
+                                                    100UL,
+                                                    1000UL,
+                                                    10000UL,
+                                                    100000UL,
+                                                    1000000UL,
+                                                    10000000UL,
+                                                    100000000UL,
+                                                    1000000000UL,
+                                                    10000000000UL,
+                                                    100000000000UL,
+                                                    1000000000000UL,
+                                                    10000000000000UL,
+                                                    100000000000000UL,
+                                                    1000000000000000UL,
+                                                    10000000000000000UL,
+                                                    100000000000000000UL,
+                                                    1000000000000000000UL,
+                                                    10000000000000000000UL};
+
+// calculate the exponent, in scientific notation, of the number.
+// this algorithm is not even close to optimized, but it has no practical
+// effect on performance: in order to have a faster algorithm, we'd need
+// to slow down performance for faster algorithms, and this is still fast.
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 int32_t
+scientific_exponent(parsed_number_string_t<UC> &num) noexcept {
+  uint64_t mantissa = num.mantissa;
+  int32_t exponent = int32_t(num.exponent);
+  while (mantissa >= 10000) {
+    mantissa /= 10000;
+    exponent += 4;
+  }
+  while (mantissa >= 100) {
+    mantissa /= 100;
+    exponent += 2;
+  }
+  while (mantissa >= 10) {
+    mantissa /= 10;
+    exponent += 1;
+  }
+  return exponent;
+}
+
+// this converts a native floating-point number to an extended-precision float.
+template <typename T>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+to_extended(T value) noexcept {
+  using equiv_uint = typename binary_format<T>::equiv_uint;
+  constexpr equiv_uint exponent_mask = binary_format<T>::exponent_mask();
+  constexpr equiv_uint mantissa_mask = binary_format<T>::mantissa_mask();
+  constexpr equiv_uint hidden_bit_mask = binary_format<T>::hidden_bit_mask();
+
+  adjusted_mantissa am;
+  int32_t bias = binary_format<T>::mantissa_explicit_bits() -
+                 binary_format<T>::minimum_exponent();
+  equiv_uint bits;
+#if FASTFLOAT_HAS_BIT_CAST
+  bits = std::bit_cast<equiv_uint>(value);
+#else
+  ::memcpy(&bits, &value, sizeof(T));
+#endif
+  if ((bits & exponent_mask) == 0) {
+    // denormal
+    am.power2 = 1 - bias;
+    am.mantissa = bits & mantissa_mask;
+  } else {
+    // normal
+    am.power2 = int32_t((bits & exponent_mask) >>
+                        binary_format<T>::mantissa_explicit_bits());
+    am.power2 -= bias;
+    am.mantissa = (bits & mantissa_mask) | hidden_bit_mask;
+  }
+
+  return am;
+}
+
+// get the extended precision value of the halfway point between b and b+u.
+// we are given a native float that represents b, so we need to adjust it
+// halfway between b and b+u.
+template <typename T>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+to_extended_halfway(T value) noexcept {
+  adjusted_mantissa am = to_extended(value);
+  am.mantissa <<= 1;
+  am.mantissa += 1;
+  am.power2 -= 1;
+  return am;
+}
+
+// round an extended-precision float to the nearest machine float.
+template <typename T, typename callback>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 void round(adjusted_mantissa &am,
+                                                         callback cb) noexcept {
+  int32_t mantissa_shift = 64 - binary_format<T>::mantissa_explicit_bits() - 1;
+  if (-am.power2 >= mantissa_shift) {
+    // have a denormal float
+    int32_t shift = -am.power2 + 1;
+    cb(am, std::min<int32_t>(shift, 64));
+    // check for round-up: if rounding-nearest carried us to the hidden bit.
+    am.power2 = (am.mantissa <
+                 (uint64_t(1) << binary_format<T>::mantissa_explicit_bits()))
+                    ? 0
+                    : 1;
+    return;
+  }
+
+  // have a normal float, use the default shift.
+  cb(am, mantissa_shift);
+
+  // check for carry
+  if (am.mantissa >=
+      (uint64_t(2) << binary_format<T>::mantissa_explicit_bits())) {
+    am.mantissa = (uint64_t(1) << binary_format<T>::mantissa_explicit_bits());
+    am.power2++;
+  }
+
+  // check for infinite: we could have carried to an infinite power
+  am.mantissa &= ~(uint64_t(1) << binary_format<T>::mantissa_explicit_bits());
+  if (am.power2 >= binary_format<T>::infinite_power()) {
+    am.power2 = binary_format<T>::infinite_power();
+    am.mantissa = 0;
+  }
+}
+
+template <typename callback>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 void
+round_nearest_tie_even(adjusted_mantissa &am, int32_t shift,
+                       callback cb) noexcept {
+  const uint64_t mask = (shift == 64) ? UINT64_MAX : (uint64_t(1) << shift) - 1;
+  const uint64_t halfway = (shift == 0) ? 0 : uint64_t(1) << (shift - 1);
+  uint64_t truncated_bits = am.mantissa & mask;
+  bool is_above = truncated_bits > halfway;
+  bool is_halfway = truncated_bits == halfway;
+
+  // shift digits into position
+  if (shift == 64) {
+    am.mantissa = 0;
+  } else {
+    am.mantissa >>= shift;
+  }
+  am.power2 += shift;
+
+  bool is_odd = (am.mantissa & 1) == 1;
+  am.mantissa += uint64_t(cb(is_odd, is_halfway, is_above));
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 void
+round_down(adjusted_mantissa &am, int32_t shift) noexcept {
+  if (shift == 64) {
+    am.mantissa = 0;
+  } else {
+    am.mantissa >>= shift;
+  }
+  am.power2 += shift;
+}
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+skip_zeros(UC const *&first, UC const *last) noexcept {
+  uint64_t val;
+  while (!cpp20_and_in_constexpr() &&
+         std::distance(first, last) >= int_cmp_len<UC>()) {
+    ::memcpy(&val, first, sizeof(uint64_t));
+    if (val != int_cmp_zeros<UC>()) {
+      break;
+    }
+    first += int_cmp_len<UC>();
+  }
+  while (first != last) {
+    if (*first != UC('0')) {
+      break;
+    }
+    first++;
+  }
+}
+
+// determine if any non-zero digits were truncated.
+// all characters must be valid digits.
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 bool
+is_truncated(UC const *first, UC const *last) noexcept {
+  // do 8-bit optimizations, can just compare to 8 literal 0s.
+  uint64_t val;
+  while (!cpp20_and_in_constexpr() &&
+         std::distance(first, last) >= int_cmp_len<UC>()) {
+    ::memcpy(&val, first, sizeof(uint64_t));
+    if (val != int_cmp_zeros<UC>()) {
+      return true;
+    }
+    first += int_cmp_len<UC>();
+  }
+  while (first != last) {
+    if (*first != UC('0')) {
+      return true;
+    }
+    ++first;
+  }
+  return false;
+}
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 bool
+is_truncated(span<const UC> s) noexcept {
+  return is_truncated(s.ptr, s.ptr + s.len());
+}
+
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+parse_eight_digits(const UC *&p, limb &value, size_t &counter,
+                   size_t &count) noexcept {
+  value = value * 100000000 + parse_eight_digits_unrolled(p);
+  p += 8;
+  counter += 8;
+  count += 8;
+}
+
+template <typename UC>
+fastfloat_really_inline FASTFLOAT_CONSTEXPR14 void
+parse_one_digit(UC const *&p, limb &value, size_t &counter,
+                size_t &count) noexcept {
+  value = value * 10 + limb(*p - UC('0'));
+  p++;
+  counter++;
+  count++;
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+add_native(bigint &big, limb power, limb value) noexcept {
+  big.mul(power);
+  big.add(value);
+}
+
+fastfloat_really_inline FASTFLOAT_CONSTEXPR20 void
+round_up_bigint(bigint &big, size_t &count) noexcept {
+  // need to round-up the digits, but need to avoid rounding
+  // ....9999 to ...10000, which could cause a false halfway point.
+  add_native(big, 10, 1);
+  count++;
+}
+
+// parse the significant digits into a big integer
+template <typename UC>
+inline FASTFLOAT_CONSTEXPR20 void
+parse_mantissa(bigint &result, parsed_number_string_t<UC> &num,
+               size_t max_digits, size_t &digits) noexcept {
+  // try to minimize the number of big integer and scalar multiplication.
+  // therefore, try to parse 8 digits at a time, and multiply by the largest
+  // scalar value (9 or 19 digits) for each step.
+  size_t counter = 0;
+  digits = 0;
+  limb value = 0;
+#ifdef FASTFLOAT_64BIT_LIMB
+  size_t step = 19;
+#else
+  size_t step = 9;
+#endif
+
+  // process all integer digits.
+  UC const *p = num.integer.ptr;
+  UC const *pend = p + num.integer.len();
+  skip_zeros(p, pend);
+  // process all digits, in increments of step per loop
+  while (p != pend) {
+    while ((std::distance(p, pend) >= 8) && (step - counter >= 8) &&
+           (max_digits - digits >= 8)) {
+      parse_eight_digits(p, value, counter, digits);
+    }
+    while (counter < step && p != pend && digits < max_digits) {
+      parse_one_digit(p, value, counter, digits);
+    }
+    if (digits == max_digits) {
+      // add the temporary value, then check if we've truncated any digits
+      add_native(result, limb(powers_of_ten_uint64[counter]), value);
+      bool truncated = is_truncated(p, pend);
+      if (num.fraction.ptr != nullptr) {
+        truncated |= is_truncated(num.fraction);
+      }
+      if (truncated) {
+        round_up_bigint(result, digits);
+      }
+      return;
+    } else {
+      add_native(result, limb(powers_of_ten_uint64[counter]), value);
+      counter = 0;
+      value = 0;
+    }
+  }
+
+  // add our fraction digits, if they're available.
+  if (num.fraction.ptr != nullptr) {
+    p = num.fraction.ptr;
+    pend = p + num.fraction.len();
+    if (digits == 0) {
+      skip_zeros(p, pend);
+    }
+    // process all digits, in increments of step per loop
+    while (p != pend) {
+      while ((std::distance(p, pend) >= 8) && (step - counter >= 8) &&
+             (max_digits - digits >= 8)) {
+        parse_eight_digits(p, value, counter, digits);
+      }
+      while (counter < step && p != pend && digits < max_digits) {
+        parse_one_digit(p, value, counter, digits);
+      }
+      if (digits == max_digits) {
+        // add the temporary value, then check if we've truncated any digits
+        add_native(result, limb(powers_of_ten_uint64[counter]), value);
+        bool truncated = is_truncated(p, pend);
+        if (truncated) {
+          round_up_bigint(result, digits);
+        }
+        return;
+      } else {
+        add_native(result, limb(powers_of_ten_uint64[counter]), value);
+        counter = 0;
+        value = 0;
+      }
+    }
+  }
+
+  if (counter != 0) {
+    add_native(result, limb(powers_of_ten_uint64[counter]), value);
+  }
+}
+
+template <typename T>
+inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+positive_digit_comp(bigint &bigmant, int32_t exponent) noexcept {
+  FASTFLOAT_ASSERT(bigmant.pow10(uint32_t(exponent)));
+  adjusted_mantissa answer;
+  bool truncated;
+  answer.mantissa = bigmant.hi64(truncated);
+  int bias = binary_format<T>::mantissa_explicit_bits() -
+             binary_format<T>::minimum_exponent();
+  answer.power2 = bigmant.bit_length() - 64 + bias;
+
+  round<T>(answer, [truncated](adjusted_mantissa &a, int32_t shift) {
+    round_nearest_tie_even(
+        a, shift,
+        [truncated](bool is_odd, bool is_halfway, bool is_above) -> bool {
+          return is_above || (is_halfway && truncated) ||
+                 (is_odd && is_halfway);
+        });
+  });
+
+  return answer;
+}
+
+// the scaling here is quite simple: we have, for the real digits `m * 10^e`,
+// and for the theoretical digits `n * 2^f`. Since `e` is always negative,
+// to scale them identically, we do `n * 2^f * 5^-f`, so we now have `m * 2^e`.
+// we then need to scale by `2^(f- e)`, and then the two significant digits
+// are of the same magnitude.
+template <typename T>
+inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa negative_digit_comp(
+    bigint &bigmant, adjusted_mantissa am, int32_t exponent) noexcept {
+  bigint &real_digits = bigmant;
+  int32_t real_exp = exponent;
+
+  // get the value of `b`, rounded down, and get a bigint representation of b+h
+  adjusted_mantissa am_b = am;
+  // gcc7 buf: use a lambda to remove the noexcept qualifier bug with
+  // -Wnoexcept-type.
+  round<T>(am_b,
+           [](adjusted_mantissa &a, int32_t shift) { round_down(a, shift); });
+  T b;
+  to_float(false, am_b, b);
+  adjusted_mantissa theor = to_extended_halfway(b);
+  bigint theor_digits(theor.mantissa);
+  int32_t theor_exp = theor.power2;
+
+  // scale real digits and theor digits to be same power.
+  int32_t pow2_exp = theor_exp - real_exp;
+  uint32_t pow5_exp = uint32_t(-real_exp);
+  if (pow5_exp != 0) {
+    FASTFLOAT_ASSERT(theor_digits.pow5(pow5_exp));
+  }
+  if (pow2_exp > 0) {
+    FASTFLOAT_ASSERT(theor_digits.pow2(uint32_t(pow2_exp)));
+  } else if (pow2_exp < 0) {
+    FASTFLOAT_ASSERT(real_digits.pow2(uint32_t(-pow2_exp)));
+  }
+
+  // compare digits, and use it to director rounding
+  int ord = real_digits.compare(theor_digits);
+  adjusted_mantissa answer = am;
+  round<T>(answer, [ord](adjusted_mantissa &a, int32_t shift) {
+    round_nearest_tie_even(
+        a, shift, [ord](bool is_odd, bool _, bool __) -> bool {
+          (void)_;  // not needed, since we've done our comparison
+          (void)__; // not needed, since we've done our comparison
+          if (ord > 0) {
+            return true;
+          } else if (ord < 0) {
+            return false;
+          } else {
+            return is_odd;
+          }
+        });
+  });
+
+  return answer;
+}
+
+// parse the significant digits as a big integer to unambiguously round the
+// the significant digits. here, we are trying to determine how to round
+// an extended float representation close to `b+h`, halfway between `b`
+// (the float rounded-down) and `b+u`, the next positive float. this
+// algorithm is always correct, and uses one of two approaches. when
+// the exponent is positive relative to the significant digits (such as
+// 1234), we create a big-integer representation, get the high 64-bits,
+// determine if any lower bits are truncated, and use that to direct
+// rounding. in case of a negative exponent relative to the significant
+// digits (such as 1.2345), we create a theoretical representation of
+// `b` as a big-integer type, scaled to the same binary exponent as
+// the actual digits. we then compare the big integer representations
+// of both, and use that to direct rounding.
+template <typename T, typename UC>
+inline FASTFLOAT_CONSTEXPR20 adjusted_mantissa
+digit_comp(parsed_number_string_t<UC> &num, adjusted_mantissa am) noexcept {
+  // remove the invalid exponent bias
+  am.power2 -= invalid_am_bias;
+
+  int32_t sci_exp = scientific_exponent(num);
+  size_t max_digits = binary_format<T>::max_digits();
+  size_t digits = 0;
+  bigint bigmant;
+  parse_mantissa(bigmant, num, max_digits, digits);
+  // can't underflow, since digits is at most max_digits.
+  int32_t exponent = sci_exp + 1 - int32_t(digits);
+  if (exponent >= 0) {
+    return positive_digit_comp<T>(bigmant, exponent);
+  } else {
+    return negative_digit_comp<T>(bigmant, am, exponent);
+  }
+}
+
+} // namespace fast_float
+
+#endif
+
+#ifndef FASTFLOAT_PARSE_NUMBER_H
+#define FASTFLOAT_PARSE_NUMBER_H
+
+
+#include <cmath>
+#include <cstring>
+#include <limits>
+#include <system_error>
+namespace fast_float {
+
+namespace detail {
+/**
+ * Special case +inf, -inf, nan, infinity, -infinity.
+ * The case comparisons could be made much faster given that we know that the
+ * strings a null-free and fixed.
+ **/
+template <typename T, typename UC>
+from_chars_result_t<UC> FASTFLOAT_CONSTEXPR14 parse_infnan(UC const *first,
+                                                           UC const *last,
+                                                           T &value) noexcept {
+  from_chars_result_t<UC> answer{};
+  answer.ptr = first;
+  answer.ec = std::errc(); // be optimistic
+  bool minusSign = false;
+  if (*first ==
+      UC('-')) { // assume first < last, so dereference without checks;
+                 // C++17 20.19.3.(7.1) explicitly forbids '+' here
+    minusSign = true;
+    ++first;
+  }
+#ifdef FASTFLOAT_ALLOWS_LEADING_PLUS // disabled by default
+  if (*first == UC('+')) {
+    ++first;
+  }
+#endif
+  if (last - first >= 3) {
+    if (fastfloat_strncasecmp(first, str_const_nan<UC>(), 3)) {
+      answer.ptr = (first += 3);
+      value = minusSign ? -std::numeric_limits<T>::quiet_NaN()
+                        : std::numeric_limits<T>::quiet_NaN();
+      // Check for possible nan(n-char-seq-opt), C++17 20.19.3.7,
+      // C11 7.20.1.3.3. At least MSVC produces nan(ind) and nan(snan).
+      if (first != last && *first == UC('(')) {
+        for (UC const *ptr = first + 1; ptr != last; ++ptr) {
+          if (*ptr == UC(')')) {
+            answer.ptr = ptr + 1; // valid nan(n-char-seq-opt)
+            break;
+          } else if (!((UC('a') <= *ptr && *ptr <= UC('z')) ||
+                       (UC('A') <= *ptr && *ptr <= UC('Z')) ||
+                       (UC('0') <= *ptr && *ptr <= UC('9')) || *ptr == UC('_')))
+            break; // forbidden char, not nan(n-char-seq-opt)
+        }
+      }
+      return answer;
+    }
+    if (fastfloat_strncasecmp(first, str_const_inf<UC>(), 3)) {
+      if ((last - first >= 8) &&
+          fastfloat_strncasecmp(first + 3, str_const_inf<UC>() + 3, 5)) {
+        answer.ptr = first + 8;
+      } else {
+        answer.ptr = first + 3;
+      }
+      value = minusSign ? -std::numeric_limits<T>::infinity()
+                        : std::numeric_limits<T>::infinity();
+      return answer;
+    }
+  }
+  answer.ec = std::errc::invalid_argument;
+  return answer;
+}
+
+/**
+ * Returns true if the floating-pointing rounding mode is to 'nearest'.
+ * It is the default on most system. This function is meant to be inexpensive.
+ * Credit : @mwalcott3
+ */
+fastfloat_really_inline bool rounds_to_nearest() noexcept {
+  // https://lemire.me/blog/2020/06/26/gcc-not-nearest/
+#if (FLT_EVAL_METHOD != 1) && (FLT_EVAL_METHOD != 0)
+  return false;
+#endif
+  // See
+  // A fast function to check your floating-point rounding mode
+  // https://lemire.me/blog/2022/11/16/a-fast-function-to-check-your-floating-point-rounding-mode/
+  //
+  // This function is meant to be equivalent to :
+  // prior: #include <cfenv>
+  //  return fegetround() == FE_TONEAREST;
+  // However, it is expected to be much faster than the fegetround()
+  // function call.
+  //
+  // The volatile keywoard prevents the compiler from computing the function
+  // at compile-time.
+  // There might be other ways to prevent compile-time optimizations (e.g.,
+  // asm). The value does not need to be std::numeric_limits<float>::min(), any
+  // small value so that 1 + x should round to 1 would do (after accounting for
+  // excess precision, as in 387 instructions).
+  static volatile float fmin = std::numeric_limits<float>::min();
+  float fmini = fmin; // we copy it so that it gets loaded at most once.
+//
+// Explanation:
+// Only when fegetround() == FE_TONEAREST do we have that
+// fmin + 1.0f == 1.0f - fmin.
+//
+// FE_UPWARD:
+//  fmin + 1.0f > 1
+//  1.0f - fmin == 1
+//
+// FE_DOWNWARD or  FE_TOWARDZERO:
+//  fmin + 1.0f == 1
+//  1.0f - fmin < 1
+//
+// Note: This may fail to be accurate if fast-math has been
+// enabled, as rounding conventions may not apply.
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#pragma warning(push)
+//  todo: is there a VS warning?
+//  see
+//  https://stackoverflow.com/questions/46079446/is-there-a-warning-for-floating-point-equality-checking-in-visual-studio-2013
+#elif defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wfloat-equal"
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wfloat-equal"
+#endif
+  return (fmini + 1.0f == 1.0f - fmini);
+#ifdef FASTFLOAT_VISUAL_STUDIO
+#pragma warning(pop)
+#elif defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif
+}
+
+} // namespace detail
+
+template <typename T> struct from_chars_caller {
+  template <typename UC>
+  FASTFLOAT_CONSTEXPR20 static from_chars_result_t<UC>
+  call(UC const *first, UC const *last, T &value,
+       parse_options_t<UC> options) noexcept {
+    return from_chars_advanced(first, last, value, options);
+  }
+};
+
+#if __STDCPP_FLOAT32_T__ == 1
+template <> struct from_chars_caller<std::float32_t> {
+  template <typename UC>
+  FASTFLOAT_CONSTEXPR20 static from_chars_result_t<UC>
+  call(UC const *first, UC const *last, std::float32_t &value,
+       parse_options_t<UC> options) noexcept {
+    // if std::float32_t is defined, and we are in C++23 mode; macro set for
+    // float32; set value to float due to equivalence between float and
+    // float32_t
+    float val;
+    auto ret = from_chars_advanced(first, last, val, options);
+    value = val;
+    return ret;
+  }
+};
+#endif
+
+#if __STDCPP_FLOAT64_T__ == 1
+template <> struct from_chars_caller<std::float64_t> {
+  template <typename UC>
+  FASTFLOAT_CONSTEXPR20 static from_chars_result_t<UC>
+  call(UC const *first, UC const *last, std::float64_t &value,
+       parse_options_t<UC> options) noexcept {
+    // if std::float64_t is defined, and we are in C++23 mode; macro set for
+    // float64; set value as double due to equivalence between double and
+    // float64_t
+    double val;
+    auto ret = from_chars_advanced(first, last, val, options);
+    value = val;
+    return ret;
+  }
+};
+#endif
+
+template <typename T, typename UC, typename>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars(UC const *first, UC const *last, T &value,
+           chars_format fmt /*= chars_format::general*/) noexcept {
+  return from_chars_caller<T>::call(first, last, value,
+                                    parse_options_t<UC>(fmt));
+}
+
+/**
+ * This function overload takes parsed_number_string_t structure that is created
+ * and populated either by from_chars_advanced function taking chars range and
+ * parsing options or other parsing custom function implemented by user.
+ */
+template <typename T, typename UC>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars_advanced(parsed_number_string_t<UC> &pns, T &value) noexcept {
+
+  static_assert(is_supported_float_type<T>(),
+                "only some floating-point types are supported");
+  static_assert(is_supported_char_type<UC>(),
+                "only char, wchar_t, char16_t and char32_t are supported");
+
+  from_chars_result_t<UC> answer;
+
+  answer.ec = std::errc(); // be optimistic
+  answer.ptr = pns.lastmatch;
+  // The implementation of the Clinger's fast path is convoluted because
+  // we want round-to-nearest in all cases, irrespective of the rounding mode
+  // selected on the thread.
+  // We proceed optimistically, assuming that detail::rounds_to_nearest()
+  // returns true.
+  if (binary_format<T>::min_exponent_fast_path() <= pns.exponent &&
+      pns.exponent <= binary_format<T>::max_exponent_fast_path() &&
+      !pns.too_many_digits) {
+    // Unfortunately, the conventional Clinger's fast path is only possible
+    // when the system rounds to the nearest float.
+    //
+    // We expect the next branch to almost always be selected.
+    // We could check it first (before the previous branch), but
+    // there might be performance advantages at having the check
+    // be last.
+    if (!cpp20_and_in_constexpr() && detail::rounds_to_nearest()) {
+      // We have that fegetround() == FE_TONEAREST.
+      // Next is Clinger's fast path.
+      if (pns.mantissa <= binary_format<T>::max_mantissa_fast_path()) {
+        value = T(pns.mantissa);
+        if (pns.exponent < 0) {
+          value = value / binary_format<T>::exact_power_of_ten(-pns.exponent);
+        } else {
+          value = value * binary_format<T>::exact_power_of_ten(pns.exponent);
+        }
+        if (pns.negative) {
+          value = -value;
+        }
+        return answer;
+      }
+    } else {
+      // We do not have that fegetround() == FE_TONEAREST.
+      // Next is a modified Clinger's fast path, inspired by Jakub Jelínek's
+      // proposal
+      if (pns.exponent >= 0 &&
+          pns.mantissa <=
+              binary_format<T>::max_mantissa_fast_path(pns.exponent)) {
+#if defined(__clang__) || defined(FASTFLOAT_32BIT)
+        // Clang may map 0 to -0.0 when fegetround() == FE_DOWNWARD
+        if (pns.mantissa == 0) {
+          value = pns.negative ? T(-0.) : T(0.);
+          return answer;
+        }
+#endif
+        value = T(pns.mantissa) *
+                binary_format<T>::exact_power_of_ten(pns.exponent);
+        if (pns.negative) {
+          value = -value;
+        }
+        return answer;
+      }
+    }
+  }
+  adjusted_mantissa am =
+      compute_float<binary_format<T>>(pns.exponent, pns.mantissa);
+  if (pns.too_many_digits && am.power2 >= 0) {
+    if (am != compute_float<binary_format<T>>(pns.exponent, pns.mantissa + 1)) {
+      am = compute_error<binary_format<T>>(pns.exponent, pns.mantissa);
+    }
+  }
+  // If we called compute_float<binary_format<T>>(pns.exponent, pns.mantissa)
+  // and we have an invalid power (am.power2 < 0), then we need to go the long
+  // way around again. This is very uncommon.
+  if (am.power2 < 0) {
+    am = digit_comp<T>(pns, am);
+  }
+  to_float(pns.negative, am, value);
+  // Test for over/underflow.
+  if ((pns.mantissa != 0 && am.mantissa == 0 && am.power2 == 0) ||
+      am.power2 == binary_format<T>::infinite_power()) {
+    answer.ec = std::errc::result_out_of_range;
+  }
+  return answer;
+}
+
+template <typename T, typename UC>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars_advanced(UC const *first, UC const *last, T &value,
+                    parse_options_t<UC> options) noexcept {
+
+  static_assert(is_supported_float_type<T>(),
+                "only some floating-point types are supported");
+  static_assert(is_supported_char_type<UC>(),
+                "only char, wchar_t, char16_t and char32_t are supported");
+
+  from_chars_result_t<UC> answer;
+#ifdef FASTFLOAT_SKIP_WHITE_SPACE // disabled by default
+  while ((first != last) && fast_float::is_space(uint8_t(*first))) {
+    first++;
+  }
+#endif
+  if (first == last) {
+    answer.ec = std::errc::invalid_argument;
+    answer.ptr = first;
+    return answer;
+  }
+  parsed_number_string_t<UC> pns =
+      parse_number_string<UC>(first, last, options);
+  if (!pns.valid) {
+    if (options.format & chars_format::no_infnan) {
+      answer.ec = std::errc::invalid_argument;
+      answer.ptr = first;
+      return answer;
+    } else {
+      return detail::parse_infnan(first, last, value);
+    }
+  }
+
+  // call overload that takes parsed_number_string_t directly.
+  return from_chars_advanced(pns, value);
+}
+
+template <typename T, typename UC, typename>
+FASTFLOAT_CONSTEXPR20 from_chars_result_t<UC>
+from_chars(UC const *first, UC const *last, T &value, int base) noexcept {
+  static_assert(is_supported_char_type<UC>(),
+                "only char, wchar_t, char16_t and char32_t are supported");
+
+  from_chars_result_t<UC> answer;
+#ifdef FASTFLOAT_SKIP_WHITE_SPACE // disabled by default
+  while ((first != last) && fast_float::is_space(uint8_t(*first))) {
+    first++;
+  }
+#endif
+  if (first == last || base < 2 || base > 36) {
+    answer.ec = std::errc::invalid_argument;
+    answer.ptr = first;
+    return answer;
+  }
+  return parse_int_string(first, last, value, base);
+}
+
+} // namespace fast_float
+
+#endif
+
