aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/cxxsupp/libcxx/include/charconv
blob: 06634fe7bc39257051de42512644e70b04947f70 (plain) (blame)
1
2
3
4
5
6
7
8
9
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
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_CHARCONV
#define _LIBCPP_CHARCONV

/*
    charconv synopsis

namespace std {

  // floating-point format for primitive numerical conversion
  enum class chars_format {
    scientific = unspecified,
    fixed = unspecified,
    hex = unspecified,
    general = fixed | scientific
  };

  // 23.20.2, primitive numerical output conversion
  struct to_chars_result {
    char* ptr;
    errc ec;
    friend bool operator==(const to_chars_result&, const to_chars_result&) = default; // since C++20
  };

  to_chars_result to_chars(char* first, char* last, see below value,
                           int base = 10);
  to_chars_result to_chars(char* first, char* last, bool value,
                           int base = 10) = delete;

  to_chars_result to_chars(char* first, char* last, float value);
  to_chars_result to_chars(char* first, char* last, double value);
  to_chars_result to_chars(char* first, char* last, long double value);

  to_chars_result to_chars(char* first, char* last, float value,
                           chars_format fmt);
  to_chars_result to_chars(char* first, char* last, double value,
                           chars_format fmt);
  to_chars_result to_chars(char* first, char* last, long double value,
                           chars_format fmt);

  to_chars_result to_chars(char* first, char* last, float value,
                           chars_format fmt, int precision);
  to_chars_result to_chars(char* first, char* last, double value,
                           chars_format fmt, int precision);
  to_chars_result to_chars(char* first, char* last, long double value,
                           chars_format fmt, int precision);

  // 23.20.3, primitive numerical input conversion
  struct from_chars_result {
    const char* ptr;
    errc ec;
    friend bool operator==(const from_chars_result&, const from_chars_result&) = default; // since C++20
  };

  from_chars_result from_chars(const char* first, const char* last,
                               see below& value, int base = 10);

  from_chars_result from_chars(const char* first, const char* last,
                               float& value,
                               chars_format fmt = chars_format::general);
  from_chars_result from_chars(const char* first, const char* last,
                               double& value,
                               chars_format fmt = chars_format::general);
  from_chars_result from_chars(const char* first, const char* last,
                               long double& value,
                               chars_format fmt = chars_format::general);

} // namespace std

*/

#include <__availability>
#include <__bits>
#include <__charconv/chars_format.h>
#include <__charconv/from_chars_result.h>
#include <__charconv/to_chars_result.h>
#include <__config>
#include <__errc>
#include <cmath> // for log2f
#include <cstdint>
#include <cstdlib> // for _LIBCPP_UNREACHABLE
#include <cstring>
#include <limits>
#include <type_traits>

#include <__debug>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

_LIBCPP_BEGIN_NAMESPACE_STD

namespace __itoa {
_LIBCPP_AVAILABILITY_TO_CHARS _LIBCPP_FUNC_VIS char* __u64toa(uint64_t __value, char* __buffer) _NOEXCEPT;
_LIBCPP_AVAILABILITY_TO_CHARS _LIBCPP_FUNC_VIS char* __u32toa(uint32_t __value, char* __buffer) _NOEXCEPT;
} // namespace __itoa

#ifndef _LIBCPP_CXX03_LANG

to_chars_result to_chars(char*, char*, bool, int = 10) = delete;
from_chars_result from_chars(const char*, const char*, bool, int = 10) = delete;

namespace __itoa
{

static _LIBCPP_CONSTEXPR uint64_t __pow10_64[] = {
    UINT64_C(0),
    UINT64_C(10),
    UINT64_C(100),
    UINT64_C(1000),
    UINT64_C(10000),
    UINT64_C(100000),
    UINT64_C(1000000),
    UINT64_C(10000000),
    UINT64_C(100000000),
    UINT64_C(1000000000),
    UINT64_C(10000000000),
    UINT64_C(100000000000),
    UINT64_C(1000000000000),
    UINT64_C(10000000000000),
    UINT64_C(100000000000000),
    UINT64_C(1000000000000000),
    UINT64_C(10000000000000000),
    UINT64_C(100000000000000000),
    UINT64_C(1000000000000000000),
    UINT64_C(10000000000000000000),
};

static _LIBCPP_CONSTEXPR uint32_t __pow10_32[] = {
    UINT32_C(0),          UINT32_C(10),       UINT32_C(100),
    UINT32_C(1000),       UINT32_C(10000),    UINT32_C(100000),
    UINT32_C(1000000),    UINT32_C(10000000), UINT32_C(100000000),
    UINT32_C(1000000000),
};

template <typename _Tp, typename = void>
struct _LIBCPP_HIDDEN __traits_base
{
    using type = uint64_t;

    static _LIBCPP_INLINE_VISIBILITY int __width(_Tp __v)
    {
        auto __t = (64 - _VSTD::__libcpp_clz(static_cast<type>(__v | 1))) * 1233 >> 12;
        return __t - (__v < __pow10_64[__t]) + 1;
    }

    _LIBCPP_AVAILABILITY_TO_CHARS
    static _LIBCPP_INLINE_VISIBILITY char* __convert(_Tp __v, char* __p)
    {
        return __u64toa(__v, __p);
    }

    static _LIBCPP_INLINE_VISIBILITY decltype(__pow10_64)& __pow() { return __pow10_64; }
};

template <typename _Tp>
struct _LIBCPP_HIDDEN
    __traits_base<_Tp, decltype(void(uint32_t{declval<_Tp>()}))>
{
    using type = uint32_t;

    static _LIBCPP_INLINE_VISIBILITY int __width(_Tp __v)
    {
        auto __t = (32 - _VSTD::__libcpp_clz(static_cast<type>(__v | 1))) * 1233 >> 12;
        return __t - (__v < __pow10_32[__t]) + 1;
    }

    _LIBCPP_AVAILABILITY_TO_CHARS
    static _LIBCPP_INLINE_VISIBILITY char* __convert(_Tp __v, char* __p)
    {
        return __u32toa(__v, __p);
    }

    static _LIBCPP_INLINE_VISIBILITY decltype(__pow10_32)& __pow() { return __pow10_32; }
};

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY bool
__mul_overflowed(unsigned char __a, _Tp __b, unsigned char& __r)
{
    auto __c = __a * __b;
    __r = __c;
    return __c > numeric_limits<unsigned char>::max();
}

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY bool
__mul_overflowed(unsigned short __a, _Tp __b, unsigned short& __r)
{
    auto __c = __a * __b;
    __r = __c;
    return __c > numeric_limits<unsigned short>::max();
}

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY bool
__mul_overflowed(_Tp __a, _Tp __b, _Tp& __r)
{
    static_assert(is_unsigned<_Tp>::value, "");
#if !defined(_LIBCPP_COMPILER_MSVC)
    return __builtin_mul_overflow(__a, __b, &__r);
#else
    bool __did = __b && (numeric_limits<_Tp>::max() / __b) < __a;
    __r = __a * __b;
    return __did;
#endif
}

template <typename _Tp, typename _Up>
inline _LIBCPP_INLINE_VISIBILITY bool
__mul_overflowed(_Tp __a, _Up __b, _Tp& __r)
{
    return __mul_overflowed(__a, static_cast<_Tp>(__b), __r);
}

template <typename _Tp>
struct _LIBCPP_HIDDEN __traits : __traits_base<_Tp>
{
    static _LIBCPP_CONSTEXPR int digits = numeric_limits<_Tp>::digits10 + 1;
    using __traits_base<_Tp>::__pow;
    using typename __traits_base<_Tp>::type;

    // precondition: at least one non-zero character available
    static _LIBCPP_INLINE_VISIBILITY char const*
    __read(char const* __p, char const* __ep, type& __a, type& __b)
    {
        type __cprod[digits];
        int __j = digits - 1;
        int __i = digits;
        do
        {
            if (!('0' <= *__p && *__p <= '9'))
                break;
            __cprod[--__i] = *__p++ - '0';
        } while (__p != __ep && __i != 0);

        __a = __inner_product(__cprod + __i + 1, __cprod + __j, __pow() + 1,
                              __cprod[__i]);
        if (__mul_overflowed(__cprod[__j], __pow()[__j - __i], __b))
            --__p;
        return __p;
    }

    template <typename _It1, typename _It2, class _Up>
    static _LIBCPP_INLINE_VISIBILITY _Up
    __inner_product(_It1 __first1, _It1 __last1, _It2 __first2, _Up __init)
    {
        for (; __first1 < __last1; ++__first1, ++__first2)
            __init = __init + *__first1 * *__first2;
        return __init;
    }
};

}  // namespace __itoa

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY _Tp
__complement(_Tp __x)
{
    static_assert(is_unsigned<_Tp>::value, "cast to unsigned first");
    return _Tp(~__x + 1);
}

template <typename _Tp>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
__to_chars_itoa(char* __first, char* __last, _Tp __value, true_type)
{
    auto __x = __to_unsigned_like(__value);
    if (__value < 0 && __first != __last)
    {
        *__first++ = '-';
        __x = __complement(__x);
    }

    return __to_chars_itoa(__first, __last, __x, false_type());
}

template <typename _Tp>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
__to_chars_itoa(char* __first, char* __last, _Tp __value, false_type)
{
    using __tx = __itoa::__traits<_Tp>;
    auto __diff = __last - __first;

    if (__tx::digits <= __diff || __tx::__width(__value) <= __diff)
        return {__tx::__convert(__value, __first), errc(0)};
    else
        return {__last, errc::value_too_large};
}

template <typename _Tp>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
__to_chars_integral(char* __first, char* __last, _Tp __value, int __base,
                    true_type)
{
    auto __x = __to_unsigned_like(__value);
    if (__value < 0 && __first != __last)
    {
        *__first++ = '-';
        __x = __complement(__x);
    }

    return __to_chars_integral(__first, __last, __x, __base, false_type());
}

template <typename _Tp>
_LIBCPP_AVAILABILITY_TO_CHARS _LIBCPP_INLINE_VISIBILITY int __to_chars_integral_width(_Tp __value, unsigned __base) {
  _LIBCPP_ASSERT(__value >= 0, "The function requires a non-negative value.");

  unsigned __base_2 = __base * __base;
  unsigned __base_3 = __base_2 * __base;
  unsigned __base_4 = __base_2 * __base_2;

  int __r = 0;
  while (true) {
    if (__value < __base)
      return __r + 1;
    if (__value < __base_2)
      return __r + 2;
    if (__value < __base_3)
      return __r + 3;
    if (__value < __base_4)
      return __r + 4;

    __value /= __base_4;
    __r += 4;
  }

  _LIBCPP_UNREACHABLE();
}

template <typename _Tp>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
__to_chars_integral(char* __first, char* __last, _Tp __value, int __base,
                    false_type)
{
  if (__base == 10)
    return __to_chars_itoa(__first, __last, __value, false_type());

  ptrdiff_t __cap = __last - __first;
  int __n = __to_chars_integral_width(__value, __base);
  if (__n > __cap)
    return {__last, errc::value_too_large};

  __last = __first + __n;
  char* __p = __last;
  do {
    unsigned __c = __value % __base;
    __value /= __base;
    *--__p = "0123456789abcdefghijklmnopqrstuvwxyz"[__c];
  } while (__value != 0);
  return {__last, errc(0)};
}

template <typename _Tp, typename enable_if<is_integral<_Tp>::value, int>::type = 0>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
to_chars(char* __first, char* __last, _Tp __value)
{
    return __to_chars_itoa(__first, __last, __value, is_signed<_Tp>());
}

template <typename _Tp, typename enable_if<is_integral<_Tp>::value, int>::type = 0>
_LIBCPP_AVAILABILITY_TO_CHARS
inline _LIBCPP_INLINE_VISIBILITY to_chars_result
to_chars(char* __first, char* __last, _Tp __value, int __base)
{
    _LIBCPP_ASSERT(2 <= __base && __base <= 36, "base not in [2, 36]");
    return __to_chars_integral(__first, __last, __value, __base,
                               is_signed<_Tp>());
}

template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__sign_combinator(_It __first, _It __last, _Tp& __value, _Fn __f, _Ts... __args)
{
    using __tl = numeric_limits<_Tp>;
    decltype(__to_unsigned_like(__value)) __x;

    bool __neg = (__first != __last && *__first == '-');
    auto __r = __f(__neg ? __first + 1 : __first, __last, __x, __args...);
    switch (__r.ec)
    {
    case errc::invalid_argument:
        return {__first, __r.ec};
    case errc::result_out_of_range:
        return __r;
    default:
        break;
    }

    if (__neg)
    {
        if (__x <= __complement(__to_unsigned_like(__tl::min())))
        {
            __x = __complement(__x);
            _VSTD::memcpy(&__value, &__x, sizeof(__x));
            return __r;
        }
    }
    else
    {
        if (__x <= __tl::max())
        {
            __value = __x;
            return __r;
        }
    }

    return {__r.ptr, errc::result_out_of_range};
}

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY bool
__in_pattern(_Tp __c)
{
    return '0' <= __c && __c <= '9';
}

struct _LIBCPP_HIDDEN __in_pattern_result
{
    bool __ok;
    int __val;

    explicit _LIBCPP_INLINE_VISIBILITY operator bool() const { return __ok; }
};

template <typename _Tp>
inline _LIBCPP_INLINE_VISIBILITY __in_pattern_result
__in_pattern(_Tp __c, int __base)
{
    if (__base <= 10)
        return {'0' <= __c && __c < '0' + __base, __c - '0'};
    else if (__in_pattern(__c))
        return {true, __c - '0'};
    else if ('a' <= __c && __c < 'a' + __base - 10)
        return {true, __c - 'a' + 10};
    else
        return {'A' <= __c && __c < 'A' + __base - 10, __c - 'A' + 10};
}

template <typename _It, typename _Tp, typename _Fn, typename... _Ts>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__subject_seq_combinator(_It __first, _It __last, _Tp& __value, _Fn __f,
                         _Ts... __args)
{
    auto __find_non_zero = [](_It __first, _It __last) {
        for (; __first != __last; ++__first)
            if (*__first != '0')
                break;
        return __first;
    };

    auto __p = __find_non_zero(__first, __last);
    if (__p == __last || !__in_pattern(*__p, __args...))
    {
        if (__p == __first)
            return {__first, errc::invalid_argument};
        else
        {
            __value = 0;
            return {__p, {}};
        }
    }

    auto __r = __f(__p, __last, __value, __args...);
    if (__r.ec == errc::result_out_of_range)
    {
        for (; __r.ptr != __last; ++__r.ptr)
        {
            if (!__in_pattern(*__r.ptr, __args...))
                break;
        }
    }

    return __r;
}

template <typename _Tp, typename enable_if<is_unsigned<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__from_chars_atoi(const char* __first, const char* __last, _Tp& __value)
{
    using __tx = __itoa::__traits<_Tp>;
    using __output_type = typename __tx::type;

    return __subject_seq_combinator(
        __first, __last, __value,
        [](const char* __first, const char* __last,
           _Tp& __value) -> from_chars_result {
            __output_type __a, __b;
            auto __p = __tx::__read(__first, __last, __a, __b);
            if (__p == __last || !__in_pattern(*__p))
            {
                __output_type __m = numeric_limits<_Tp>::max();
                if (__m >= __a && __m - __a >= __b)
                {
                    __value = __a + __b;
                    return {__p, {}};
                }
            }
            return {__p, errc::result_out_of_range};
        });
}

template <typename _Tp, typename enable_if<is_signed<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__from_chars_atoi(const char* __first, const char* __last, _Tp& __value)
{
    using __t = decltype(__to_unsigned_like(__value));
    return __sign_combinator(__first, __last, __value, __from_chars_atoi<__t>);
}

template <typename _Tp, typename enable_if<is_unsigned<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__from_chars_integral(const char* __first, const char* __last, _Tp& __value,
                      int __base)
{
    if (__base == 10)
        return __from_chars_atoi(__first, __last, __value);

    return __subject_seq_combinator(
        __first, __last, __value,
        [](const char* __p, const char* __lastx, _Tp& __value,
           int __base) -> from_chars_result {
            using __tl = numeric_limits<_Tp>;
            auto __digits = __tl::digits / log2f(float(__base));
            _Tp __a = __in_pattern(*__p++, __base).__val, __b = 0;

            for (int __i = 1; __p != __lastx; ++__i, ++__p)
            {
                if (auto __c = __in_pattern(*__p, __base))
                {
                    if (__i < __digits - 1)
                        __a = __a * __base + __c.__val;
                    else
                    {
                        if (!__itoa::__mul_overflowed(__a, __base, __a))
                            ++__p;
                        __b = __c.__val;
                        break;
                    }
                }
                else
                    break;
            }

            if (__p == __lastx || !__in_pattern(*__p, __base))
            {
                if (__tl::max() - __a >= __b)
                {
                    __value = __a + __b;
                    return {__p, {}};
                }
            }
            return {__p, errc::result_out_of_range};
        },
        __base);
}

template <typename _Tp, typename enable_if<is_signed<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
__from_chars_integral(const char* __first, const char* __last, _Tp& __value,
                      int __base)
{
    using __t = decltype(__to_unsigned_like(__value));
    return __sign_combinator(__first, __last, __value,
                             __from_chars_integral<__t>, __base);
}

template <typename _Tp, typename enable_if<is_integral<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
from_chars(const char* __first, const char* __last, _Tp& __value)
{
    return __from_chars_atoi(__first, __last, __value);
}

template <typename _Tp, typename enable_if<is_integral<_Tp>::value, int>::type = 0>
inline _LIBCPP_INLINE_VISIBILITY from_chars_result
from_chars(const char* __first, const char* __last, _Tp& __value, int __base)
{
    _LIBCPP_ASSERT(2 <= __base && __base <= 36, "base not in [2, 36]");
    return __from_chars_integral(__first, __last, __value, __base);
}

// Floating-point implementation starts here.
// Unlike the other parts of charconv this is only available in C++17 and newer.
#if _LIBCPP_STD_VER > 14

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, float __value);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, double __value);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, long double __value);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, float __value, chars_format __fmt);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, double __value, chars_format __fmt);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, long double __value, chars_format __fmt);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, float __value, chars_format __fmt, int __precision);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, double __value, chars_format __fmt, int __precision);

_LIBCPP_AVAILABILITY_TO_CHARS_FLOATING_POINT _LIBCPP_FUNC_VIS
to_chars_result to_chars(char* __first, char* __last, long double __value, chars_format __fmt, int __precision);

#  endif // _LIBCPP_STD_VER > 14
#endif // _LIBCPP_CXX03_LANG

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS

#endif // _LIBCPP_CHARCONV