projects / babeltrace.git / blame
| Commit | Line | Data |
|---|---|---|
| 30586bf0 PP |
1 | // |
| 2 | // span for C++98 and later. | |
| 3 | // Based on http://wg21.link/p0122r7 | |
| 4 | // For more information see https://github.com/martinmoene/span-lite | |
| 5 | // | |
| 6 | // Copyright 2018-2021 Martin Moene | |
| 7 | // | |
| 8 | // Distributed under the Boost Software License, Version 1.0. | |
| 9 | // (See accompanying file LICENSE.txt or copy at http://www.boost.org/LICENSE_1_0.txt) | |
| 10 | ||
| 11 | #ifndef NONSTD_SPAN_HPP_INCLUDED | |
| 12 | #define NONSTD_SPAN_HPP_INCLUDED | |
| 13 | ||
| 14 | #define span_lite_MAJOR 0 | |
| 15 | #define span_lite_MINOR 11 | |
| 16 | #define span_lite_PATCH 0 | |
| 17 | ||
| 18 | #define span_lite_VERSION span_STRINGIFY(span_lite_MAJOR) "." span_STRINGIFY(span_lite_MINOR) "." span_STRINGIFY(span_lite_PATCH) | |
| 19 | ||
| 20 | #define span_STRINGIFY( x ) span_STRINGIFY_( x ) | |
| 21 | #define span_STRINGIFY_( x ) #x | |
| 22 | ||
| 23 | // span configuration: | |
| 24 | ||
| 25 | #define span_SPAN_DEFAULT 0 | |
| 26 | #define span_SPAN_NONSTD 1 | |
| 27 | #define span_SPAN_STD 2 | |
| 28 | ||
| 29 | // tweak header support: | |
| 30 | ||
| 31 | #ifdef __has_include | |
| 32 | # if __has_include(<nonstd/span.tweak.hpp>) | |
| 33 | # include <nonstd/span.tweak.hpp> | |
| 34 | # endif | |
| 35 | #define span_HAVE_TWEAK_HEADER 1 | |
| 36 | #else | |
| 37 | #define span_HAVE_TWEAK_HEADER 0 | |
| 38 | //# pragma message("span.hpp: Note: Tweak header not supported.") | |
| 39 | #endif | |
| 40 | ||
| 41 | // span selection and configuration: | |
| 42 | ||
| 43 | #define span_HAVE( feature ) ( span_HAVE_##feature ) | |
| 44 | ||
| 45 | #ifndef span_CONFIG_SELECT_SPAN | |
| 46 | # define span_CONFIG_SELECT_SPAN ( span_HAVE_STD_SPAN ? span_SPAN_STD : span_SPAN_NONSTD ) | |
| 47 | #endif | |
| 48 | ||
| 49 | #ifndef span_CONFIG_EXTENT_TYPE | |
| 50 | # define span_CONFIG_EXTENT_TYPE std::size_t | |
| 51 | #endif | |
| 52 | ||
| 53 | #ifndef span_CONFIG_SIZE_TYPE | |
| 54 | # define span_CONFIG_SIZE_TYPE std::size_t | |
| 55 | #endif | |
| 56 | ||
| 57 | #ifdef span_CONFIG_INDEX_TYPE | |
| 58 | # error `span_CONFIG_INDEX_TYPE` is deprecated since v0.7.0; it is replaced by `span_CONFIG_SIZE_TYPE`. | |
| 59 | #endif | |
| 60 | ||
| 61 | // span configuration (features): | |
| 62 | ||
| 63 | #ifndef span_FEATURE_WITH_INITIALIZER_LIST_P2447 | |
| 64 | # define span_FEATURE_WITH_INITIALIZER_LIST_P2447 0 | |
| 65 | #endif | |
| 66 | ||
| 67 | #ifndef span_FEATURE_WITH_CONTAINER | |
| 68 | #ifdef span_FEATURE_WITH_CONTAINER_TO_STD | |
| 69 | # define span_FEATURE_WITH_CONTAINER span_IN_STD( span_FEATURE_WITH_CONTAINER_TO_STD ) | |
| 70 | #else | |
| 71 | # define span_FEATURE_WITH_CONTAINER 0 | |
| 72 | # define span_FEATURE_WITH_CONTAINER_TO_STD 0 | |
| 73 | #endif | |
| 74 | #endif | |
| 75 | ||
| 76 | #ifndef span_FEATURE_CONSTRUCTION_FROM_STDARRAY_ELEMENT_TYPE | |
| 77 | # define span_FEATURE_CONSTRUCTION_FROM_STDARRAY_ELEMENT_TYPE 0 | |
| 78 | #endif | |
| 79 | ||
| 80 | #ifndef span_FEATURE_MEMBER_AT | |
| 81 | # define span_FEATURE_MEMBER_AT 0 | |
| 82 | #endif | |
| 83 | ||
| 84 | #ifndef span_FEATURE_MEMBER_BACK_FRONT | |
| 85 | # define span_FEATURE_MEMBER_BACK_FRONT 1 | |
| 86 | #endif | |
| 87 | ||
| 88 | #ifndef span_FEATURE_MEMBER_CALL_OPERATOR | |
| 89 | # define span_FEATURE_MEMBER_CALL_OPERATOR 0 | |
| 90 | #endif | |
| 91 | ||
| 92 | #ifndef span_FEATURE_MEMBER_SWAP | |
| 93 | # define span_FEATURE_MEMBER_SWAP 0 | |
| 94 | #endif | |
| 95 | ||
| 96 | #ifndef span_FEATURE_NON_MEMBER_FIRST_LAST_SUB | |
| 97 | # define span_FEATURE_NON_MEMBER_FIRST_LAST_SUB 0 | |
| 98 | #elif span_FEATURE_NON_MEMBER_FIRST_LAST_SUB | |
| 99 | # define span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_SPAN 1 | |
| 100 | # define span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_CONTAINER 1 | |
| 101 | #endif | |
| 102 | ||
| 103 | #ifndef span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_SPAN | |
| 104 | # define span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_SPAN 0 | |
| 105 | #endif | |
| 106 | ||
| 107 | #ifndef span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_CONTAINER | |
| 108 | # define span_FEATURE_NON_MEMBER_FIRST_LAST_SUB_CONTAINER 0 | |
| 109 | #endif | |
| 110 | ||
| 111 | #ifndef span_FEATURE_COMPARISON | |
| 112 | # define span_FEATURE_COMPARISON 0 // Note: C++20 does not provide comparison | |
| 113 | #endif | |
| 114 | ||
| 115 | #ifndef span_FEATURE_SAME | |
| 116 | # define span_FEATURE_SAME 0 | |
| 117 | #endif | |
| 118 | ||
| 119 | #if span_FEATURE_SAME && !span_FEATURE_COMPARISON | |
| 120 | # error `span_FEATURE_SAME` requires `span_FEATURE_COMPARISON` | |
| 121 | #endif | |
| 122 | ||
| 123 | #ifndef span_FEATURE_MAKE_SPAN | |
| 124 | #ifdef span_FEATURE_MAKE_SPAN_TO_STD | |
| 125 | # define span_FEATURE_MAKE_SPAN span_IN_STD( span_FEATURE_MAKE_SPAN_TO_STD ) | |
| 126 | #else | |
| 127 | # define span_FEATURE_MAKE_SPAN 0 | |
| 128 | # define span_FEATURE_MAKE_SPAN_TO_STD 0 | |
| 129 | #endif | |
| 130 | #endif | |
| 131 | ||
| 132 | #ifndef span_FEATURE_BYTE_SPAN | |
| 133 | # define span_FEATURE_BYTE_SPAN 0 | |
| 134 | #endif | |
| 135 | ||
| 136 | // Control presence of exception handling (try and auto discover): | |
| 137 | ||
| 138 | #ifndef span_CONFIG_NO_EXCEPTIONS | |
| 139 | # if defined(_MSC_VER) | |
| 140 | # include <cstddef> // for _HAS_EXCEPTIONS | |
| 141 | # endif | |
| 142 | # if defined(__cpp_exceptions) || defined(__EXCEPTIONS) || (_HAS_EXCEPTIONS) | |
| 143 | # define span_CONFIG_NO_EXCEPTIONS 0 | |
| 144 | # else | |
| 145 | # define span_CONFIG_NO_EXCEPTIONS 1 | |
| 146 | # undef span_CONFIG_CONTRACT_VIOLATION_THROWS | |
| 147 | # undef span_CONFIG_CONTRACT_VIOLATION_TERMINATES | |
| 148 | # define span_CONFIG_CONTRACT_VIOLATION_THROWS 0 | |
| 149 | # define span_CONFIG_CONTRACT_VIOLATION_TERMINATES 1 | |
| 150 | # endif | |
| 151 | #endif | |
| 152 | ||
| 153 | // Control pre- and postcondition violation behaviour: | |
| 154 | ||
| 155 | #if defined( span_CONFIG_CONTRACT_LEVEL_ON ) | |
| 156 | # define span_CONFIG_CONTRACT_LEVEL_MASK 0x11 | |
| 157 | #elif defined( span_CONFIG_CONTRACT_LEVEL_OFF ) | |
| 158 | # define span_CONFIG_CONTRACT_LEVEL_MASK 0x00 | |
| 159 | #elif defined( span_CONFIG_CONTRACT_LEVEL_EXPECTS_ONLY ) | |
| 160 | # define span_CONFIG_CONTRACT_LEVEL_MASK 0x01 | |
| 161 | #elif defined( span_CONFIG_CONTRACT_LEVEL_ENSURES_ONLY ) | |
| 162 | # define span_CONFIG_CONTRACT_LEVEL_MASK 0x10 | |
| 163 | #else | |
| 164 | # define span_CONFIG_CONTRACT_LEVEL_MASK 0x11 | |
| 165 | #endif | |
| 166 | ||
| 167 | #if defined( span_CONFIG_CONTRACT_VIOLATION_THROWS ) | |
| 168 | # define span_CONFIG_CONTRACT_VIOLATION_THROWS_V span_CONFIG_CONTRACT_VIOLATION_THROWS | |
| 169 | #else | |
| 170 | # define span_CONFIG_CONTRACT_VIOLATION_THROWS_V 0 | |
| 171 | #endif | |
| 172 | ||
| 173 | #if defined( span_CONFIG_CONTRACT_VIOLATION_THROWS ) && span_CONFIG_CONTRACT_VIOLATION_THROWS && \ | |
| 174 | defined( span_CONFIG_CONTRACT_VIOLATION_TERMINATES ) && span_CONFIG_CONTRACT_VIOLATION_TERMINATES | |
| 175 | # error Please define none or one of span_CONFIG_CONTRACT_VIOLATION_THROWS and span_CONFIG_CONTRACT_VIOLATION_TERMINATES to 1, but not both. | |
| 176 | #endif | |
| 177 | ||
| 178 | // C++ language version detection (C++23 is speculative): | |
| 179 | // Note: VC14.0/1900 (VS2015) lacks too much from C++14. | |
| 180 | ||
| 181 | #ifndef span_CPLUSPLUS | |
| 182 | # if defined(_MSVC_LANG ) && !defined(__clang__) | |
| 183 | # define span_CPLUSPLUS (_MSC_VER == 1900 ? 201103L : _MSVC_LANG ) | |
| 184 | # else | |
| 185 | # define span_CPLUSPLUS __cplusplus | |
| 186 | # endif | |
| 187 | #endif | |
| 188 | ||
| 189 | #define span_CPP98_OR_GREATER ( span_CPLUSPLUS >= 199711L ) | |
| 190 | #define span_CPP11_OR_GREATER ( span_CPLUSPLUS >= 201103L ) | |
| 191 | #define span_CPP14_OR_GREATER ( span_CPLUSPLUS >= 201402L ) | |
| 192 | #define span_CPP17_OR_GREATER ( span_CPLUSPLUS >= 201703L ) | |
| 193 | #define span_CPP20_OR_GREATER ( span_CPLUSPLUS >= 202002L ) | |
| 194 | #define span_CPP23_OR_GREATER ( span_CPLUSPLUS >= 202300L ) | |
| 195 | ||
| 196 | // C++ language version (represent 98 as 3): | |
| 197 | ||
| 198 | #define span_CPLUSPLUS_V ( span_CPLUSPLUS / 100 - (span_CPLUSPLUS > 200000 ? 2000 : 1994) ) | |
| 199 | ||
| 200 | #define span_IN_STD( v ) ( ((v) == 98 ? 3 : (v)) >= span_CPLUSPLUS_V ) | |
| 201 | ||
| 202 | #define span_CONFIG( feature ) ( span_CONFIG_##feature ) | |
| 203 | #define span_FEATURE( feature ) ( span_FEATURE_##feature ) | |
| 204 | #define span_FEATURE_TO_STD( feature ) ( span_IN_STD( span_FEATURE( feature##_TO_STD ) ) ) | |
| 205 | ||
| 206 | // Use C++20 std::span if available and requested: | |
| 207 | ||
| 208 | #if span_CPP20_OR_GREATER && defined(__has_include ) | |
| 209 | # if __has_include( <span> ) | |
| 210 | # define span_HAVE_STD_SPAN 1 | |
| 211 | # else | |
| 212 | # define span_HAVE_STD_SPAN 0 | |
| 213 | # endif | |
| 214 | #else | |
| 215 | # define span_HAVE_STD_SPAN 0 | |
| 216 | #endif | |
| 217 | ||
| 218 | #define span_USES_STD_SPAN ( (span_CONFIG_SELECT_SPAN == span_SPAN_STD) || ((span_CONFIG_SELECT_SPAN == span_SPAN_DEFAULT) && span_HAVE_STD_SPAN) ) | |
| 219 | ||
| 220 | // | |
| 221 | // Use C++20 std::span: | |
| 222 | // | |
| 223 | ||
| 224 | #if span_USES_STD_SPAN | |
| 225 | ||
| 226 | #include <span> | |
| 227 | ||
| 228 | namespace nonstd { | |
| 229 | ||
| 230 | using std::span; | |
| 231 | using std::dynamic_extent; | |
| 232 | ||
| 233 | // Note: C++20 does not provide comparison | |
| 234 | // using std::operator==; | |
| 235 | // using std::operator!=; | |
| 236 | // using std::operator<; | |
| 237 | // using std::operator<=; | |
| 238 | // using std::operator>; | |
| 239 | // using std::operator>=; | |
| 240 | } // namespace nonstd | |
| 241 | ||
| 242 | #else // span_USES_STD_SPAN | |
| 243 | ||
| 244 | #include <algorithm> | |
| 245 | ||
| 246 | // Compiler versions: | |
| 247 | // | |
| 248 | // MSVC++ 6.0 _MSC_VER == 1200 span_COMPILER_MSVC_VERSION == 60 (Visual Studio 6.0) | |
| 249 | // MSVC++ 7.0 _MSC_VER == 1300 span_COMPILER_MSVC_VERSION == 70 (Visual Studio .NET 2002) | |
| 250 | // MSVC++ 7.1 _MSC_VER == 1310 span_COMPILER_MSVC_VERSION == 71 (Visual Studio .NET 2003) | |
| 251 | // MSVC++ 8.0 _MSC_VER == 1400 span_COMPILER_MSVC_VERSION == 80 (Visual Studio 2005) | |
| 252 | // MSVC++ 9.0 _MSC_VER == 1500 span_COMPILER_MSVC_VERSION == 90 (Visual Studio 2008) | |
| 253 | // MSVC++ 10.0 _MSC_VER == 1600 span_COMPILER_MSVC_VERSION == 100 (Visual Studio 2010) | |
| 254 | // MSVC++ 11.0 _MSC_VER == 1700 span_COMPILER_MSVC_VERSION == 110 (Visual Studio 2012) | |
| 255 | // MSVC++ 12.0 _MSC_VER == 1800 span_COMPILER_MSVC_VERSION == 120 (Visual Studio 2013) | |
| 256 | // MSVC++ 14.0 _MSC_VER == 1900 span_COMPILER_MSVC_VERSION == 140 (Visual Studio 2015) | |
| 257 | // MSVC++ 14.1 _MSC_VER >= 1910 span_COMPILER_MSVC_VERSION == 141 (Visual Studio 2017) | |
| 258 | // MSVC++ 14.2 _MSC_VER >= 1920 span_COMPILER_MSVC_VERSION == 142 (Visual Studio 2019) | |
| 259 | ||
| 260 | #if defined(_MSC_VER ) && !defined(__clang__) | |
| 261 | # define span_COMPILER_MSVC_VER (_MSC_VER ) | |
| 262 | # define span_COMPILER_MSVC_VERSION (_MSC_VER / 10 - 10 * ( 5 + (_MSC_VER < 1900 ) ) ) | |
| 263 | #else | |
| 264 | # define span_COMPILER_MSVC_VER 0 | |
| 265 | # define span_COMPILER_MSVC_VERSION 0 | |
| 266 | #endif | |
| 267 | ||
| 268 | #define span_COMPILER_VERSION( major, minor, patch ) ( 10 * ( 10 * (major) + (minor) ) + (patch) ) | |
| 269 | ||
| 270 | #if defined(__clang__) | |
| 271 | # define span_COMPILER_CLANG_VERSION span_COMPILER_VERSION(__clang_major__, __clang_minor__, __clang_patchlevel__) | |
| 272 | #else | |
| 273 | # define span_COMPILER_CLANG_VERSION 0 | |
| 274 | #endif | |
| 275 | ||
| 276 | #if defined(__GNUC__) && !defined(__clang__) | |
| 277 | # define span_COMPILER_GNUC_VERSION span_COMPILER_VERSION(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__) | |
| 278 | #else | |
| 279 | # define span_COMPILER_GNUC_VERSION 0 | |
| 280 | #endif | |
| 281 | ||
| 282 | // half-open range [lo..hi): | |
| 283 | #define span_BETWEEN( v, lo, hi ) ( (lo) <= (v) && (v) < (hi) ) | |
| 284 | ||
| 285 | // Compiler warning suppression: | |
| 286 | ||
| 287 | #if defined(__clang__) | |
| 288 | # pragma clang diagnostic push | |
| 289 | # pragma clang diagnostic ignored "-Wundef" | |
| 290 | # pragma clang diagnostic ignored "-Wmismatched-tags" | |
| 291 | # define span_RESTORE_WARNINGS() _Pragma( "clang diagnostic pop" ) | |
| 292 | ||
| 293 | #elif defined __GNUC__ | |
| 294 | # pragma GCC diagnostic push | |
| 295 | # pragma GCC diagnostic ignored "-Wundef" | |
| 296 | # define span_RESTORE_WARNINGS() _Pragma( "GCC diagnostic pop" ) | |
| 297 | ||
| 298 | #elif span_COMPILER_MSVC_VER >= 1900 | |
| 299 | # define span_DISABLE_MSVC_WARNINGS(codes) __pragma(warning(push)) __pragma(warning(disable: codes)) | |
| 300 | # define span_RESTORE_WARNINGS() __pragma(warning(pop )) | |
| 301 | ||
| 302 | // Suppress the following MSVC GSL warnings: | |
| 303 | // - C26439, gsl::f.6 : special function 'function' can be declared 'noexcept' | |
| 304 | // - C26440, gsl::f.6 : function 'function' can be declared 'noexcept' | |
| 305 | // - C26472, gsl::t.1 : don't use a static_cast for arithmetic conversions; | |
| 306 | // use brace initialization, gsl::narrow_cast or gsl::narrow | |
| 307 | // - C26473: gsl::t.1 : don't cast between pointer types where the source type and the target type are the same | |
| 308 | // - C26481: gsl::b.1 : don't use pointer arithmetic. Use span instead | |
| 309 | // - C26490: gsl::t.1 : don't use reinterpret_cast | |
| 310 | ||
| 311 | span_DISABLE_MSVC_WARNINGS( 26439 26440 26472 26473 26481 26490 ) | |
| 312 | ||
| 313 | #else | |
| 314 | # define span_RESTORE_WARNINGS() /*empty*/ | |
| 315 | #endif | |
| 316 | ||
| 317 | // Presence of language and library features: | |
| 318 | ||
| 319 | #ifdef _HAS_CPP0X | |
| 320 | # define span_HAS_CPP0X _HAS_CPP0X | |
| 321 | #else | |
| 322 | # define span_HAS_CPP0X 0 | |
| 323 | #endif | |
| 324 | ||
| 325 | #define span_CPP11_80 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1400) | |
| 326 | #define span_CPP11_90 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1500) | |
| 327 | #define span_CPP11_100 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1600) | |
| 328 | #define span_CPP11_110 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1700) | |
| 329 | #define span_CPP11_120 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1800) | |
| 330 | #define span_CPP11_140 (span_CPP11_OR_GREATER || span_COMPILER_MSVC_VER >= 1900) | |
| 331 | ||
| 332 | #define span_CPP14_000 (span_CPP14_OR_GREATER) | |
| 333 | #define span_CPP14_120 (span_CPP14_OR_GREATER || span_COMPILER_MSVC_VER >= 1800) | |
| 334 | #define span_CPP14_140 (span_CPP14_OR_GREATER || span_COMPILER_MSVC_VER >= 1900) | |
| 335 | ||
| 336 | #define span_CPP17_000 (span_CPP17_OR_GREATER) | |
| 337 | ||
| 338 | // Presence of C++11 language features: | |
| 339 | ||
| 340 | #define span_HAVE_ALIAS_TEMPLATE span_CPP11_140 | |
| 341 | #define span_HAVE_AUTO span_CPP11_100 | |
| 342 | #define span_HAVE_CONSTEXPR_11 span_CPP11_140 | |
| 343 | #define span_HAVE_DEFAULT_FUNCTION_TEMPLATE_ARG span_CPP11_120 | |
| 344 | #define span_HAVE_EXPLICIT_CONVERSION span_CPP11_140 | |
| 345 | #define span_HAVE_INITIALIZER_LIST span_CPP11_120 | |
| 346 | #define span_HAVE_IS_DEFAULT span_CPP11_140 | |
| 347 | #define span_HAVE_IS_DELETE span_CPP11_140 | |
| 348 | #define span_HAVE_NOEXCEPT span_CPP11_140 | |
| 349 | #define span_HAVE_NORETURN ( span_CPP11_140 && ! span_BETWEEN( span_COMPILER_GNUC_VERSION, 1, 480 ) ) | |
| 350 | #define span_HAVE_NULLPTR span_CPP11_100 | |
| 351 | #define span_HAVE_STATIC_ASSERT span_CPP11_100 | |
| 352 | ||
| 353 | // Presence of C++14 language features: | |
| 354 | ||
| 355 | #define span_HAVE_CONSTEXPR_14 span_CPP14_000 | |
| 356 | ||
| 357 | // Presence of C++17 language features: | |
| 358 | ||
| 359 | #define span_HAVE_DEPRECATED span_CPP17_000 | |
| 360 | #define span_HAVE_NODISCARD span_CPP17_000 | |
| 361 | ||
| 362 | // MSVC: template parameter deduction guides since Visual Studio 2017 v15.7 | |
| 363 | ||
| 364 | #if defined(__cpp_deduction_guides) | |
| 365 | # define span_HAVE_DEDUCTION_GUIDES 1 | |
| 366 | #else | |
| 367 | # define span_HAVE_DEDUCTION_GUIDES (span_CPP17_OR_GREATER && ! span_BETWEEN( span_COMPILER_MSVC_VER, 1, 1913 )) | |
| 368 | #endif | |
| 369 | ||
| 370 | // Presence of C++ library features: | |
| 371 | ||
| 372 | #define span_HAVE_ADDRESSOF span_CPP17_000 | |
| 373 | #define span_HAVE_ARRAY span_CPP11_110 | |
| 374 | #define span_HAVE_BYTE span_CPP17_000 | |
| 375 | #define span_HAVE_CONDITIONAL span_CPP11_120 | |
| 376 | #define span_HAVE_CONTAINER_DATA_METHOD (span_CPP11_140 || ( span_COMPILER_MSVC_VER >= 1500 && span_HAS_CPP0X )) | |
| 377 | #define span_HAVE_DATA span_CPP17_000 | |
| 378 | #define span_HAVE_LONGLONG span_CPP11_80 | |
| 379 | #define span_HAVE_REMOVE_CONST span_CPP11_110 | |
| 380 | #define span_HAVE_SNPRINTF span_CPP11_140 | |
| 381 | #define span_HAVE_STRUCT_BINDING span_CPP11_120 | |
| 382 | #define span_HAVE_TYPE_TRAITS span_CPP11_90 | |
| 383 | ||
| 384 | // Presence of byte-lite: | |
| 385 | ||
| 386 | #ifdef NONSTD_BYTE_LITE_HPP | |
| 387 | # define span_HAVE_NONSTD_BYTE 1 | |
| 388 | #else | |
| 389 | # define span_HAVE_NONSTD_BYTE 0 | |
| 390 | #endif | |
| 391 | ||
| 392 | // C++ feature usage: | |
| 393 | ||
| 394 | #if span_HAVE_ADDRESSOF | |
| 395 | # define span_ADDRESSOF(x) std::addressof(x) | |
| 396 | #else | |
| 397 | # define span_ADDRESSOF(x) (&x) | |
| 398 | #endif | |
| 399 | ||
| 400 | #if span_HAVE_CONSTEXPR_11 | |
| 401 | # define span_constexpr constexpr | |
| 402 | #else | |
| 403 | # define span_constexpr /*span_constexpr*/ | |
| 404 | #endif | |
| 405 | ||
| 406 | #if span_HAVE_CONSTEXPR_14 | |
| 407 | # define span_constexpr14 constexpr | |
| 408 | #else | |
| 409 | # define span_constexpr14 /*span_constexpr*/ | |
| 410 | #endif | |
| 411 | ||
| 412 | #if span_HAVE_EXPLICIT_CONVERSION | |
| 413 | # define span_explicit explicit | |
| 414 | #else | |
| 415 | # define span_explicit /*explicit*/ | |
| 416 | #endif | |
| 417 | ||
| 418 | #if span_HAVE_IS_DELETE | |
| 419 | # define span_is_delete = delete | |
| 420 | #else | |
| 421 | # define span_is_delete | |
| 422 | #endif | |
| 423 | ||
| 424 | #if span_HAVE_IS_DELETE | |
| 425 | # define span_is_delete_access public | |
| 426 | #else | |
| 427 | # define span_is_delete_access private | |
| 428 | #endif | |
| 429 | ||
| 430 | #if span_HAVE_NOEXCEPT && ! span_CONFIG_CONTRACT_VIOLATION_THROWS_V | |
| 431 | # define span_noexcept noexcept | |
| 432 | #else | |
| 433 | # define span_noexcept /*noexcept*/ | |
| 434 | #endif | |
| 435 | ||
| 436 | #if span_HAVE_NULLPTR | |
| 437 | # define span_nullptr nullptr | |
| 438 | #else | |
| 439 | # define span_nullptr NULL | |
| 440 | #endif | |
| 441 | ||
| 442 | #if span_HAVE_DEPRECATED | |
| 443 | # define span_deprecated(msg) [[deprecated(msg)]] | |
| 444 | #else | |
| 445 | # define span_deprecated(msg) /*[[deprecated]]*/ | |
| 446 | #endif | |
| 447 | ||
| 448 | #if span_HAVE_NODISCARD | |
| 449 | # define span_nodiscard [[nodiscard]] | |
| 450 | #else | |
| 451 | # define span_nodiscard /*[[nodiscard]]*/ | |
| 452 | #endif | |
| 453 | ||
| 454 | #if span_HAVE_NORETURN | |
| 455 | # define span_noreturn [[noreturn]] | |
| 456 | #else | |
| 457 | # define span_noreturn /*[[noreturn]]*/ | |
| 458 | #endif | |
| 459 | ||
| 460 | // Other features: | |
| 461 | ||
| 462 | #define span_HAVE_CONSTRAINED_SPAN_CONTAINER_CTOR span_HAVE_DEFAULT_FUNCTION_TEMPLATE_ARG | |
| 463 | #define span_HAVE_ITERATOR_CTOR span_HAVE_DEFAULT_FUNCTION_TEMPLATE_ARG | |
| 464 | ||
| 465 | // Additional includes: | |
| 466 | ||
| 467 | #if span_HAVE( ADDRESSOF ) | |
| 468 | # include <memory> | |
| 469 | #endif | |
| 470 | ||
| 471 | #if span_HAVE( ARRAY ) | |
| 472 | # include <array> | |
| 473 | #endif | |
| 474 | ||
| 475 | #if span_HAVE( BYTE ) | |
| 476 | # include <cstddef> | |
| 477 | #endif | |
| 478 | ||
| 479 | #if span_HAVE( DATA ) | |
| 480 | # include <iterator> // for std::data(), std::size() | |
| 481 | #endif | |
| 482 | ||
| 483 | #if span_HAVE( TYPE_TRAITS ) | |
| 484 | # include <type_traits> | |
| 485 | #endif | |
| 486 | ||
| 487 | #if ! span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) | |
| 488 | # include <vector> | |
| 489 | #endif | |
| 490 | ||
| 491 | #if span_FEATURE( MEMBER_AT ) > 1 | |
| 492 | # include <cstdio> | |
| 493 | #endif | |
| 494 | ||
| 495 | #if ! span_CONFIG( NO_EXCEPTIONS ) | |
| 496 | # include <stdexcept> | |
| 497 | #endif | |
| 498 | ||
| 499 | // Contract violation | |
| 500 | ||
| 501 | #define span_ELIDE_CONTRACT_EXPECTS ( 0 == ( span_CONFIG_CONTRACT_LEVEL_MASK & 0x01 ) ) | |
| 502 | #define span_ELIDE_CONTRACT_ENSURES ( 0 == ( span_CONFIG_CONTRACT_LEVEL_MASK & 0x10 ) ) | |
| 503 | ||
| 504 | #if span_ELIDE_CONTRACT_EXPECTS | |
| 505 | # define span_constexpr_exp span_constexpr | |
| 506 | # define span_EXPECTS( cond ) /* Expect elided */ | |
| 507 | #else | |
| 508 | # define span_constexpr_exp span_constexpr14 | |
| 509 | # define span_EXPECTS( cond ) span_CONTRACT_CHECK( "Precondition", cond ) | |
| 510 | #endif | |
| 511 | ||
| 512 | #if span_ELIDE_CONTRACT_ENSURES | |
| 513 | # define span_constexpr_ens span_constexpr | |
| 514 | # define span_ENSURES( cond ) /* Ensures elided */ | |
| 515 | #else | |
| 516 | # define span_constexpr_ens span_constexpr14 | |
| 517 | # define span_ENSURES( cond ) span_CONTRACT_CHECK( "Postcondition", cond ) | |
| 518 | #endif | |
| 519 | ||
| 520 | #define span_CONTRACT_CHECK( type, cond ) \ | |
| 521 | cond ? static_cast< void >( 0 ) \ | |
| 522 | : nonstd::span_lite::detail::report_contract_violation( span_LOCATION( __FILE__, __LINE__ ) ": " type " violation." ) | |
| 523 | ||
| 524 | #ifdef __GNUG__ | |
| 525 | # define span_LOCATION( file, line ) file ":" span_STRINGIFY( line ) | |
| 526 | #else | |
| 527 | # define span_LOCATION( file, line ) file "(" span_STRINGIFY( line ) ")" | |
| 528 | #endif | |
| 529 | ||
| 530 | // Method enabling | |
| 531 | ||
| 532 | #if span_HAVE( DEFAULT_FUNCTION_TEMPLATE_ARG ) | |
| 533 | ||
| 534 | #define span_REQUIRES_0(VA) \ | |
| 535 | template< bool B = (VA), typename std::enable_if<B, int>::type = 0 > | |
| 536 | ||
| 537 | # if span_BETWEEN( span_COMPILER_MSVC_VERSION, 1, 140 ) | |
| 538 | // VS 2013 and earlier seem to have trouble with SFINAE for default non-type arguments | |
| 539 | # define span_REQUIRES_T(VA) \ | |
| 540 | , typename = typename std::enable_if< ( VA ), nonstd::span_lite::detail::enabler >::type | |
| 541 | # else | |
| 542 | # define span_REQUIRES_T(VA) \ | |
| 543 | , typename std::enable_if< (VA), int >::type = 0 | |
| 544 | # endif | |
| 545 | ||
| 546 | #define span_REQUIRES_R(R, VA) \ | |
| 547 | typename std::enable_if< (VA), R>::type | |
| 548 | ||
| 549 | #define span_REQUIRES_A(VA) \ | |
| 550 | , typename std::enable_if< (VA), void*>::type = nullptr | |
| 551 | ||
| 552 | #else | |
| 553 | ||
| 554 | # define span_REQUIRES_0(VA) /*empty*/ | |
| 555 | # define span_REQUIRES_T(VA) /*empty*/ | |
| 556 | # define span_REQUIRES_R(R, VA) R | |
| 557 | # define span_REQUIRES_A(VA) /*empty*/ | |
| 558 | ||
| 559 | #endif | |
| 560 | ||
| 561 | namespace nonstd { | |
| 562 | namespace span_lite { | |
| 563 | ||
| 564 | // [views.constants], constants | |
| 565 | ||
| 566 | typedef span_CONFIG_EXTENT_TYPE extent_t; | |
| 567 | typedef span_CONFIG_SIZE_TYPE size_t; | |
| 568 | ||
| 569 | span_constexpr const extent_t dynamic_extent = static_cast<extent_t>( -1 ); | |
| 570 | ||
| 571 | template< class T, extent_t Extent = dynamic_extent > | |
| 572 | class span; | |
| 573 | ||
| 574 | // Tag to select span constructor taking a container (prevent ms-gsl warning C26426): | |
| 575 | ||
| 576 | struct with_container_t { span_constexpr with_container_t() span_noexcept {} }; | |
| 577 | const span_constexpr with_container_t with_container; | |
| 578 | ||
| 579 | // C++11 emulation: | |
| 580 | ||
| 581 | namespace std11 { | |
| 582 | ||
| 583 | #if span_HAVE( REMOVE_CONST ) | |
| 584 | ||
| 585 | using std::remove_cv; | |
| 586 | using std::remove_const; | |
| 587 | using std::remove_volatile; | |
| 588 | ||
| 589 | #else | |
| 590 | ||
| 591 | template< class T > struct remove_const { typedef T type; }; | |
| 592 | template< class T > struct remove_const< T const > { typedef T type; }; | |
| 593 | ||
| 594 | template< class T > struct remove_volatile { typedef T type; }; | |
| 595 | template< class T > struct remove_volatile< T volatile > { typedef T type; }; | |
| 596 | ||
| 597 | template< class T > | |
| 598 | struct remove_cv | |
| 599 | { | |
| 600 | typedef typename std11::remove_volatile< typename std11::remove_const< T >::type >::type type; | |
| 601 | }; | |
| 602 | ||
| 603 | #endif // span_HAVE( REMOVE_CONST ) | |
| 604 | ||
| 605 | #if span_HAVE( TYPE_TRAITS ) | |
| 606 | ||
| 607 | using std::is_same; | |
| 608 | using std::is_signed; | |
| 609 | using std::integral_constant; | |
| 610 | using std::true_type; | |
| 611 | using std::false_type; | |
| 612 | using std::remove_reference; | |
| 613 | ||
| 614 | #else | |
| 615 | ||
| 616 | template< class T, T v > struct integral_constant { enum { value = v }; }; | |
| 617 | typedef integral_constant< bool, true > true_type; | |
| 618 | typedef integral_constant< bool, false > false_type; | |
| 619 | ||
| 620 | template< class T, class U > struct is_same : false_type{}; | |
| 621 | template< class T > struct is_same<T, T> : true_type{}; | |
| 622 | ||
| 623 | template< typename T > struct is_signed : false_type {}; | |
| 624 | template<> struct is_signed<signed char> : true_type {}; | |
| 625 | template<> struct is_signed<signed int > : true_type {}; | |
| 626 | template<> struct is_signed<signed long> : true_type {}; | |
| 627 | ||
| 628 | #endif | |
| 629 | ||
| 630 | } // namespace std11 | |
| 631 | ||
| 632 | // C++17 emulation: | |
| 633 | ||
| 634 | namespace std17 { | |
| 635 | ||
| 636 | template< bool v > struct bool_constant : std11::integral_constant<bool, v>{}; | |
| 637 | ||
| 638 | #if span_CPP11_120 | |
| 639 | ||
| 640 | template< class...> | |
| 641 | using void_t = void; | |
| 642 | ||
| 643 | #endif | |
| 644 | ||
| 645 | #if span_HAVE( DATA ) | |
| 646 | ||
| 647 | using std::data; | |
| 648 | using std::size; | |
| 649 | ||
| 650 | #elif span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) | |
| 651 | ||
| 652 | template< typename T, std::size_t N > | |
| 653 | inline span_constexpr auto size( const T(&)[N] ) span_noexcept -> size_t | |
| 654 | { | |
| 655 | return N; | |
| 656 | } | |
| 657 | ||
| 658 | template< typename C > | |
| 659 | inline span_constexpr auto size( C const & cont ) -> decltype( cont.size() ) | |
| 660 | { | |
| 661 | return cont.size(); | |
| 662 | } | |
| 663 | ||
| 664 | template< typename T, std::size_t N > | |
| 665 | inline span_constexpr auto data( T(&arr)[N] ) span_noexcept -> T* | |
| 666 | { | |
| 667 | return &arr[0]; | |
| 668 | } | |
| 669 | ||
| 670 | template< typename C > | |
| 671 | inline span_constexpr auto data( C & cont ) -> decltype( cont.data() ) | |
| 672 | { | |
| 673 | return cont.data(); | |
| 674 | } | |
| 675 | ||
| 676 | template< typename C > | |
| 677 | inline span_constexpr auto data( C const & cont ) -> decltype( cont.data() ) | |
| 678 | { | |
| 679 | return cont.data(); | |
| 680 | } | |
| 681 | ||
| 682 | template< typename E > | |
| 683 | inline span_constexpr auto data( std::initializer_list<E> il ) span_noexcept -> E const * | |
| 684 | { | |
| 685 | return il.begin(); | |
| 686 | } | |
| 687 | ||
| 688 | #endif // span_HAVE( DATA ) | |
| 689 | ||
| 690 | #if span_HAVE( BYTE ) | |
| 691 | using std::byte; | |
| 692 | #elif span_HAVE( NONSTD_BYTE ) | |
| 693 | using nonstd::byte; | |
| 694 | #endif | |
| 695 | ||
| 696 | } // namespace std17 | |
| 697 | ||
| 698 | // C++20 emulation: | |
| 699 | ||
| 700 | namespace std20 { | |
| 701 | ||
| 702 | #if span_HAVE( DEDUCTION_GUIDES ) | |
| 703 | template< class T > | |
| 704 | using iter_reference_t = decltype( *std::declval<T&>() ); | |
| 705 | #endif | |
| 706 | ||
| 707 | } // namespace std20 | |
| 708 | ||
| 709 | // Implementation details: | |
| 710 | ||
| 711 | namespace detail { | |
| 712 | ||
| 713 | /*enum*/ struct enabler{}; | |
| 714 | ||
| 715 | template< typename T > | |
| 716 | span_constexpr bool is_positive( T x ) | |
| 717 | { | |
| 718 | return std11::is_signed<T>::value ? x >= 0 : true; | |
| 719 | } | |
| 720 | ||
| 721 | #if span_HAVE( TYPE_TRAITS ) | |
| 722 | ||
| 723 | template< class Q > | |
| 724 | struct is_span_oracle : std::false_type{}; | |
| 725 | ||
| 726 | template< class T, span_CONFIG_EXTENT_TYPE Extent > | |
| 727 | struct is_span_oracle< span<T, Extent> > : std::true_type{}; | |
| 728 | ||
| 729 | template< class Q > | |
| 730 | struct is_span : is_span_oracle< typename std::remove_cv<Q>::type >{}; | |
| 731 | ||
| 732 | template< class Q > | |
| 733 | struct is_std_array_oracle : std::false_type{}; | |
| 734 | ||
| 735 | #if span_HAVE( ARRAY ) | |
| 736 | ||
| 737 | template< class T, std::size_t Extent > | |
| 738 | struct is_std_array_oracle< std::array<T, Extent> > : std::true_type{}; | |
| 739 | ||
| 740 | #endif | |
| 741 | ||
| 742 | template< class Q > | |
| 743 | struct is_std_array : is_std_array_oracle< typename std::remove_cv<Q>::type >{}; | |
| 744 | ||
| 745 | template< class Q > | |
| 746 | struct is_array : std::false_type {}; | |
| 747 | ||
| 748 | template< class T > | |
| 749 | struct is_array<T[]> : std::true_type {}; | |
| 750 | ||
| 751 | template< class T, std::size_t N > | |
| 752 | struct is_array<T[N]> : std::true_type {}; | |
| 753 | ||
| 754 | #if span_CPP11_140 && ! span_BETWEEN( span_COMPILER_GNUC_VERSION, 1, 500 ) | |
| 755 | ||
| 756 | template< class, class = void > | |
| 757 | struct has_size_and_data : std::false_type{}; | |
| 758 | ||
| 759 | template< class C > | |
| 760 | struct has_size_and_data | |
| 761 | < | |
| 762 | C, std17::void_t< | |
| 763 | decltype( std17::size(std::declval<C>()) ), | |
| 764 | decltype( std17::data(std::declval<C>()) ) > | |
| 765 | > : std::true_type{}; | |
| 766 | ||
| 767 | template< class, class, class = void > | |
| 768 | struct is_compatible_element : std::false_type {}; | |
| 769 | ||
| 770 | template< class C, class E > | |
| 771 | struct is_compatible_element | |
| 772 | < | |
| 773 | C, E, std17::void_t< | |
| 774 | decltype( std17::data(std::declval<C>()) ) > | |
| 775 | > : std::is_convertible< typename std::remove_pointer<decltype( std17::data( std::declval<C&>() ) )>::type(*)[], E(*)[] >{}; | |
| 776 | ||
| 777 | template< class C > | |
| 778 | struct is_container : std17::bool_constant | |
| 779 | < | |
| 780 | ! is_span< C >::value | |
| 781 | && ! is_array< C >::value | |
| 782 | && ! is_std_array< C >::value | |
| 783 | && has_size_and_data< C >::value | |
| 784 | >{}; | |
| 785 | ||
| 786 | template< class C, class E > | |
| 787 | struct is_compatible_container : std17::bool_constant | |
| 788 | < | |
| 789 | is_container<C>::value | |
| 790 | && is_compatible_element<C,E>::value | |
| 791 | >{}; | |
| 792 | ||
| 793 | #else // span_CPP11_140 | |
| 794 | ||
| 795 | template< | |
| 796 | class C, class E | |
| 797 | span_REQUIRES_T(( | |
| 798 | ! is_span< C >::value | |
| 799 | && ! is_array< C >::value | |
| 800 | && ! is_std_array< C >::value | |
| 801 | && ( std::is_convertible< typename std::remove_pointer<decltype( std17::data( std::declval<C&>() ) )>::type(*)[], E(*)[] >::value) | |
| 802 | // && has_size_and_data< C >::value | |
| 803 | )) | |
| 804 | , class = decltype( std17::size(std::declval<C>()) ) | |
| 805 | , class = decltype( std17::data(std::declval<C>()) ) | |
| 806 | > | |
| 807 | struct is_compatible_container : std::true_type{}; | |
| 808 | ||
| 809 | #endif // span_CPP11_140 | |
| 810 | ||
| 811 | #endif // span_HAVE( TYPE_TRAITS ) | |
| 812 | ||
| 813 | #if ! span_CONFIG( NO_EXCEPTIONS ) | |
| 814 | #if span_FEATURE( MEMBER_AT ) > 1 | |
| 815 | ||
| 816 | // format index and size: | |
| 817 | ||
| 818 | #if defined(__clang__) | |
| 819 | # pragma clang diagnostic ignored "-Wlong-long" | |
| 820 | #elif defined __GNUC__ | |
| 821 | # pragma GCC diagnostic ignored "-Wformat=ll" | |
| 822 | # pragma GCC diagnostic ignored "-Wlong-long" | |
| 823 | #endif | |
| 824 | ||
| 825 | span_noreturn inline void throw_out_of_range( size_t idx, size_t size ) | |
| 826 | { | |
| 827 | const char fmt[] = "span::at(): index '%lli' is out of range [0..%lli)"; | |
| 828 | char buffer[ 2 * 20 + sizeof fmt ]; | |
| 829 | sprintf( buffer, fmt, static_cast<long long>(idx), static_cast<long long>(size) ); | |
| 830 | ||
| 831 | throw std::out_of_range( buffer ); | |
| 832 | } | |
| 833 | ||
| 834 | #else // MEMBER_AT | |
| 835 | ||
| 836 | span_noreturn inline void throw_out_of_range( size_t /*idx*/, size_t /*size*/ ) | |
| 837 | { | |
| 838 | throw std::out_of_range( "span::at(): index outside span" ); | |
| 839 | } | |
| 840 | #endif // MEMBER_AT | |
| 841 | #endif // NO_EXCEPTIONS | |
| 842 | ||
| 843 | #if span_CONFIG( CONTRACT_VIOLATION_THROWS_V ) | |
| 844 | ||
| 845 | struct contract_violation : std::logic_error | |
| 846 | { | |
| 847 | explicit contract_violation( char const * const message ) | |
| 848 | : std::logic_error( message ) | |
| 849 | {} | |
| 850 | }; | |
| 851 | ||
| 852 | inline void report_contract_violation( char const * msg ) | |
| 853 | { | |
| 854 | throw contract_violation( msg ); | |
| 855 | } | |
| 856 | ||
| 857 | #else // span_CONFIG( CONTRACT_VIOLATION_THROWS_V ) | |
| 858 | ||
| 859 | span_noreturn inline void report_contract_violation( char const * /*msg*/ ) span_noexcept | |
| 860 | { | |
| 861 | std::terminate(); | |
| 862 | } | |
| 863 | ||
| 864 | #endif // span_CONFIG( CONTRACT_VIOLATION_THROWS_V ) | |
| 865 | ||
| 866 | } // namespace detail | |
| 867 | ||
| 868 | // Prevent signed-unsigned mismatch: | |
| 869 | ||
| 870 | #define span_sizeof(T) static_cast<extent_t>( sizeof(T) ) | |
| 871 | ||
| 872 | template< class T > | |
| 873 | inline span_constexpr size_t to_size( T size ) | |
| 874 | { | |
| 875 | return static_cast<size_t>( size ); | |
| 876 | } | |
| 877 | ||
| 878 | // | |
| 879 | // [views.span] - A view over a contiguous, single-dimension sequence of objects | |
| 880 | // | |
| 881 | template< class T, extent_t Extent /*= dynamic_extent*/ > | |
| 882 | class span | |
| 883 | { | |
| 884 | public: | |
| 885 | // constants and types | |
| 886 | ||
| 887 | typedef T element_type; | |
| 888 | typedef typename std11::remove_cv< T >::type value_type; | |
| 889 | ||
| 890 | typedef T & reference; | |
| 891 | typedef T * pointer; | |
| 892 | typedef T const * const_pointer; | |
| 893 | typedef T const & const_reference; | |
| 894 | ||
| 895 | typedef size_t size_type; | |
| 896 | typedef extent_t extent_type; | |
| 897 | ||
| 898 | typedef pointer iterator; | |
| 899 | typedef const_pointer const_iterator; | |
| 900 | ||
| 901 | typedef std::ptrdiff_t difference_type; | |
| 902 | ||
| 903 | typedef std::reverse_iterator< iterator > reverse_iterator; | |
| 904 | typedef std::reverse_iterator< const_iterator > const_reverse_iterator; | |
| 905 | ||
| 906 | // static constexpr extent_type extent = Extent; | |
| 907 | enum { extent = Extent }; | |
| 908 | ||
| 909 | // 26.7.3.2 Constructors, copy, and assignment [span.cons] | |
| 910 | ||
| 911 | span_REQUIRES_0( | |
| 912 | ( Extent == 0 ) || | |
| 913 | ( Extent == dynamic_extent ) | |
| 914 | ) | |
| 915 | span_constexpr span() span_noexcept | |
| 916 | : data_( span_nullptr ) | |
| 917 | , size_( 0 ) | |
| 918 | { | |
| 919 | // span_EXPECTS( data() == span_nullptr ); | |
| 920 | // span_EXPECTS( size() == 0 ); | |
| 921 | } | |
| 922 | ||
| 923 | #if span_HAVE( ITERATOR_CTOR ) | |
| 924 | // Didn't yet succeed in combining the next two constructors: | |
| 925 | ||
| 926 | span_constexpr_exp span( std::nullptr_t, size_type count ) | |
| 927 | : data_( span_nullptr ) | |
| 928 | , size_( count ) | |
| 929 | { | |
| 930 | span_EXPECTS( data_ == span_nullptr && count == 0 ); | |
| 931 | } | |
| 932 | ||
| 933 | template< typename It | |
| 934 | span_REQUIRES_T(( | |
| 935 | std::is_convertible<decltype(*std::declval<It&>()), element_type &>::value | |
| 936 | )) | |
| 937 | > | |
| 938 | span_constexpr_exp span( It first, size_type count ) | |
| 939 | : data_( to_address( first ) ) | |
| 940 | , size_( count ) | |
| 941 | { | |
| 942 | span_EXPECTS( | |
| 943 | ( data_ == span_nullptr && count == 0 ) || | |
| 944 | ( data_ != span_nullptr && detail::is_positive( count ) ) | |
| 945 | ); | |
| 946 | } | |
| 947 | #else | |
| 948 | span_constexpr_exp span( pointer ptr, size_type count ) | |
| 949 | : data_( ptr ) | |
| 950 | , size_( count ) | |
| 951 | { | |
| 952 | span_EXPECTS( | |
| 953 | ( ptr == span_nullptr && count == 0 ) || | |
| 954 | ( ptr != span_nullptr && detail::is_positive( count ) ) | |
| 955 | ); | |
| 956 | } | |
| 957 | #endif | |
| 958 | ||
| 959 | #if span_HAVE( ITERATOR_CTOR ) | |
| 960 | template< typename It, typename End | |
| 961 | span_REQUIRES_T(( | |
| 962 | std::is_convertible<decltype(&*std::declval<It&>()), element_type *>::value | |
| 963 | && ! std::is_convertible<End, std::size_t>::value | |
| 964 | )) | |
| 965 | > | |
| 966 | span_constexpr_exp span( It first, End last ) | |
| 967 | : data_( to_address( first ) ) | |
| 968 | , size_( to_size( last - first ) ) | |
| 969 | { | |
| 970 | span_EXPECTS( | |
| 971 | last - first >= 0 | |
| 972 | ); | |
| 973 | } | |
| 974 | #else | |
| 975 | span_constexpr_exp span( pointer first, pointer last ) | |
| 976 | : data_( first ) | |
| 977 | , size_( to_size( last - first ) ) | |
| 978 | { | |
| 979 | span_EXPECTS( | |
| 980 | last - first >= 0 | |
| 981 | ); | |
| 982 | } | |
| 983 | #endif | |
| 984 | ||
| 985 | template< std::size_t N | |
| 986 | span_REQUIRES_T(( | |
| 987 | (Extent == dynamic_extent || Extent == static_cast<extent_t>(N)) | |
| 988 | && std::is_convertible< value_type(*)[], element_type(*)[] >::value | |
| 989 | )) | |
| 990 | > | |
| 991 | span_constexpr span( element_type ( &arr )[ N ] ) span_noexcept | |
| 992 | : data_( span_ADDRESSOF( arr[0] ) ) | |
| 993 | , size_( N ) | |
| 994 | {} | |
| 995 | ||
| 996 | #if span_HAVE( ARRAY ) | |
| 997 | ||
| 998 | template< std::size_t N | |
| 999 | span_REQUIRES_T(( | |
| 1000 | (Extent == dynamic_extent || Extent == static_cast<extent_t>(N)) | |
| 1001 | && std::is_convertible< value_type(*)[], element_type(*)[] >::value | |
| 1002 | )) | |
| 1003 | > | |
| 1004 | # if span_FEATURE( CONSTRUCTION_FROM_STDARRAY_ELEMENT_TYPE ) | |
| 1005 | span_constexpr span( std::array< element_type, N > & arr ) span_noexcept | |
| 1006 | # else | |
| 1007 | span_constexpr span( std::array< value_type, N > & arr ) span_noexcept | |
| 1008 | # endif | |
| 1009 | : data_( arr.data() ) | |
| 1010 | , size_( to_size( arr.size() ) ) | |
| 1011 | {} | |
| 1012 | ||
| 1013 | template< std::size_t N | |
| 1014 | # if span_HAVE( DEFAULT_FUNCTION_TEMPLATE_ARG ) | |
| 1015 | span_REQUIRES_T(( | |
| 1016 | (Extent == dynamic_extent || Extent == static_cast<extent_t>(N)) | |
| 1017 | && std::is_convertible< value_type(*)[], element_type(*)[] >::value | |
| 1018 | )) | |
| 1019 | # endif | |
| 1020 | > | |
| 1021 | span_constexpr span( std::array< value_type, N> const & arr ) span_noexcept | |
| 1022 | : data_( arr.data() ) | |
| 1023 | , size_( to_size( arr.size() ) ) | |
| 1024 | {} | |
| 1025 | ||
| 1026 | #endif // span_HAVE( ARRAY ) | |
| 1027 | ||
| 1028 | #if span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) | |
| 1029 | template< class Container | |
| 1030 | span_REQUIRES_T(( | |
| 1031 | detail::is_compatible_container< Container, element_type >::value | |
| 1032 | )) | |
| 1033 | > | |
| 1034 | span_constexpr span( Container & cont ) | |
| 1035 | : data_( std17::data( cont ) ) | |
| 1036 | , size_( to_size( std17::size( cont ) ) ) | |
| 1037 | {} | |
| 1038 | ||
| 1039 | template< class Container | |
| 1040 | span_REQUIRES_T(( | |
| 1041 | std::is_const< element_type >::value | |
| 1042 | && detail::is_compatible_container< Container, element_type >::value | |
| 1043 | )) | |
| 1044 | > | |
| 1045 | span_constexpr span( Container const & cont ) | |
| 1046 | : data_( std17::data( cont ) ) | |
| 1047 | , size_( to_size( std17::size( cont ) ) ) | |
| 1048 | {} | |
| 1049 | ||
| 1050 | #endif // span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) | |
| 1051 | ||
| 1052 | #if span_FEATURE( WITH_CONTAINER ) | |
| 1053 | ||
| 1054 | template< class Container > | |
| 1055 | span_constexpr span( with_container_t, Container & cont ) | |
| 1056 | : data_( cont.size() == 0 ? span_nullptr : span_ADDRESSOF( cont[0] ) ) | |
| 1057 | , size_( to_size( cont.size() ) ) | |
| 1058 | {} | |
| 1059 | ||
| 1060 | template< class Container > | |
| 1061 | span_constexpr span( with_container_t, Container const & cont ) | |
| 1062 | : data_( cont.size() == 0 ? span_nullptr : const_cast<pointer>( span_ADDRESSOF( cont[0] ) ) ) | |
| 1063 | , size_( to_size( cont.size() ) ) | |
| 1064 | {} | |
| 1065 | #endif | |
| 1066 | ||
| 1067 | #if span_FEATURE( WITH_INITIALIZER_LIST_P2447 ) && span_HAVE( INITIALIZER_LIST ) | |
| 1068 | ||
| 1069 | // constexpr explicit(extent != dynamic_extent) span(std::initializer_list<value_type> il) noexcept; | |
| 1070 | ||
| 1071 | #if !span_BETWEEN( span_COMPILER_MSVC_VERSION, 120, 130 ) | |
| 1072 | ||
| 1073 | template< extent_t U = Extent | |
| 1074 | span_REQUIRES_T(( | |
| 1075 | U != dynamic_extent | |
| 1076 | )) | |
| 1077 | > | |
| 1078 | #if span_COMPILER_GNUC_VERSION >= 900 // prevent GCC's "-Winit-list-lifetime" | |
| 1079 | span_constexpr14 explicit span( std::initializer_list<value_type> il ) span_noexcept | |
| 1080 | { | |
| 1081 | data_ = il.begin(); | |
| 1082 | size_ = il.size(); | |
| 1083 | } | |
| 1084 | #else | |
| 1085 | span_constexpr explicit span( std::initializer_list<value_type> il ) span_noexcept | |
| 1086 | : data_( il.begin() ) | |
| 1087 | , size_( il.size() ) | |
| 1088 | {} | |
| 1089 | #endif | |
| 1090 | ||
| 1091 | #endif // MSVC 120 (VS2013) | |
| 1092 | ||
| 1093 | template< extent_t U = Extent | |
| 1094 | span_REQUIRES_T(( | |
| 1095 | U == dynamic_extent | |
| 1096 | )) | |
| 1097 | > | |
| 1098 | #if span_COMPILER_GNUC_VERSION >= 900 // prevent GCC's "-Winit-list-lifetime" | |
| 1099 | span_constexpr14 /*explicit*/ span( std::initializer_list<value_type> il ) span_noexcept | |
| 1100 | { | |
| 1101 | data_ = il.begin(); | |
| 1102 | size_ = il.size(); | |
| 1103 | } | |
| 1104 | #else | |
| 1105 | span_constexpr /*explicit*/ span( std::initializer_list<value_type> il ) span_noexcept | |
| 1106 | : data_( il.begin() ) | |
| 1107 | , size_( il.size() ) | |
| 1108 | {} | |
| 1109 | #endif | |
| 1110 | ||
| 1111 | #endif // P2447 | |
| 1112 | ||
| 1113 | #if span_HAVE( IS_DEFAULT ) | |
| 1114 | span_constexpr span( span const & other ) span_noexcept = default; | |
| 1115 | ||
| 1116 | ~span() span_noexcept = default; | |
| 1117 | ||
| 1118 | span_constexpr14 span & operator=( span const & other ) span_noexcept = default; | |
| 1119 | #else | |
| 1120 | span_constexpr span( span const & other ) span_noexcept | |
| 1121 | : data_( other.data_ ) | |
| 1122 | , size_( other.size_ ) | |
| 1123 | {} | |
| 1124 | ||
| 1125 | ~span() span_noexcept | |
| 1126 | {} | |
| 1127 | ||
| 1128 | span_constexpr14 span & operator=( span const & other ) span_noexcept | |
| 1129 | { | |
| 1130 | data_ = other.data_; | |
| 1131 | size_ = other.size_; | |
| 1132 | ||
| 1133 | return *this; | |
| 1134 | } | |
| 1135 | #endif | |
| 1136 | ||
| 1137 | template< class OtherElementType, extent_type OtherExtent | |
| 1138 | span_REQUIRES_T(( | |
| 1139 | (Extent == dynamic_extent || OtherExtent == dynamic_extent || Extent == OtherExtent) | |
| 1140 | && std::is_convertible<OtherElementType(*)[], element_type(*)[]>::value | |
| 1141 | )) | |
| 1142 | > | |
| 1143 | span_constexpr_exp span( span<OtherElementType, OtherExtent> const & other ) span_noexcept | |
| 1144 | : data_( other.data() ) | |
| 1145 | , size_( other.size() ) | |
| 1146 | { | |
| 1147 | span_EXPECTS( OtherExtent == dynamic_extent || other.size() == to_size(OtherExtent) ); | |
| 1148 | } | |
| 1149 | ||
| 1150 | // 26.7.3.3 Subviews [span.sub] | |
| 1151 | ||
| 1152 | template< extent_type Count > | |
| 1153 | span_constexpr_exp span< element_type, Count > | |
| 1154 | first() const | |
| 1155 | { | |
| 1156 | span_EXPECTS( detail::is_positive( Count ) && Count <= size() ); | |
| 1157 | ||
| 1158 | return span< element_type, Count >( data(), Count ); | |
| 1159 | } | |
| 1160 | ||
| 1161 | template< extent_type Count > | |
| 1162 | span_constexpr_exp span< element_type, Count > | |
| 1163 | last() const | |
| 1164 | { | |
| 1165 | span_EXPECTS( detail::is_positive( Count ) && Count <= size() ); | |
| 1166 | ||
| 1167 | return span< element_type, Count >( data() + (size() - Count), Count ); | |
| 1168 | } | |
| 1169 | ||
| 1170 | #if span_HAVE( DEFAULT_FUNCTION_TEMPLATE_ARG ) | |
| 1171 | template< size_type Offset, extent_type Count = dynamic_extent > | |
| 1172 | #else | |
| 1173 | template< size_type Offset, extent_type Count /*= dynamic_extent*/ > | |
| 1174 | #endif | |
| 1175 | span_constexpr_exp span< element_type, Count > | |
| 1176 | subspan() const | |
| 1177 | { | |
| 1178 | span_EXPECTS( | |
| 1179 | ( detail::is_positive( Offset ) && Offset <= size() ) && | |
| 1180 | ( Count == dynamic_extent || (detail::is_positive( Count ) && Count + Offset <= size()) ) | |
| 1181 | ); | |
| 1182 | ||
| 1183 | return span< element_type, Count >( | |
| 1184 | data() + Offset, Count != dynamic_extent ? Count : (Extent != dynamic_extent ? Extent - Offset : size() - Offset) ); | |
| 1185 | } | |
| 1186 | ||
| 1187 | span_constexpr_exp span< element_type, dynamic_extent > | |
| 1188 | first( size_type count ) const | |
| 1189 | { | |
| 1190 | span_EXPECTS( detail::is_positive( count ) && count <= size() ); | |
| 1191 | ||
| 1192 | return span< element_type, dynamic_extent >( data(), count ); | |
| 1193 | } | |
| 1194 | ||
| 1195 | span_constexpr_exp span< element_type, dynamic_extent > | |
| 1196 | last( size_type count ) const | |
| 1197 | { | |
| 1198 | span_EXPECTS( detail::is_positive( count ) && count <= size() ); | |
| 1199 | ||
| 1200 | return span< element_type, dynamic_extent >( data() + ( size() - count ), count ); | |
| 1201 | } | |
| 1202 | ||
| 1203 | span_constexpr_exp span< element_type, dynamic_extent > | |
| 1204 | subspan( size_type offset, size_type count = static_cast<size_type>(dynamic_extent) ) const | |
| 1205 | { | |
| 1206 | span_EXPECTS( | |
| 1207 | ( ( detail::is_positive( offset ) && offset <= size() ) ) && | |
| 1208 | ( count == static_cast<size_type>(dynamic_extent) || ( detail::is_positive( count ) && offset + count <= size() ) ) | |
| 1209 | ); | |
| 1210 | ||
| 1211 | return span< element_type, dynamic_extent >( | |
| 1212 | data() + offset, count == static_cast<size_type>(dynamic_extent) ? size() - offset : count ); | |
| 1213 | } | |
| 1214 | ||
| 1215 | // 26.7.3.4 Observers [span.obs] | |
| 1216 | ||
| 1217 | span_constexpr size_type size() const span_noexcept | |
| 1218 | { | |
| 1219 | return size_; | |
| 1220 | } | |
| 1221 | ||
| 1222 | span_constexpr std::ptrdiff_t ssize() const span_noexcept | |
| 1223 | { | |
| 1224 | return static_cast<std::ptrdiff_t>( size_ ); | |
| 1225 | } | |
| 1226 | ||
| 1227 | span_constexpr size_type size_bytes() const span_noexcept | |
| 1228 | { | |
| 1229 | return size() * to_size( sizeof( element_type ) ); | |
| 1230 | } | |
| 1231 | ||
| 1232 | span_nodiscard span_constexpr bool empty() const span_noexcept | |
| 1233 | { | |
| 1234 | return size() == 0; | |
| 1235 | } | |
| 1236 | ||
| 1237 | // 26.7.3.5 Element access [span.elem] | |
| 1238 | ||
| 1239 | span_constexpr_exp reference operator[]( size_type idx ) const | |
| 1240 | { | |
| 1241 | span_EXPECTS( detail::is_positive( idx ) && idx < size() ); | |
| 1242 | ||
| 1243 | return *( data() + idx ); | |
| 1244 | } | |
| 1245 | ||
| 1246 | #if span_FEATURE( MEMBER_CALL_OPERATOR ) | |
| 1247 | span_deprecated("replace operator() with operator[]") | |
| 1248 | ||
| 1249 | span_constexpr_exp reference operator()( size_type idx ) const | |
| 1250 | { | |
| 1251 | span_EXPECTS( detail::is_positive( idx ) && idx < size() ); | |
| 1252 | ||
| 1253 | return *( data() + idx ); | |
| 1254 | } | |
| 1255 | #endif | |
| 1256 | ||
| 1257 | #if span_FEATURE( MEMBER_AT ) | |
| 1258 | span_constexpr14 reference at( size_type idx ) const | |
| 1259 | { | |
| 1260 | #if span_CONFIG( NO_EXCEPTIONS ) | |
| 1261 | return this->operator[]( idx ); | |
| 1262 | #else | |
| 1263 | if ( !detail::is_positive( idx ) || size() <= idx ) | |
| 1264 | { | |
| 1265 | detail::throw_out_of_range( idx, size() ); | |
| 1266 | } | |
| 1267 | return *( data() + idx ); | |
| 1268 | #endif | |
| 1269 | } | |
| 1270 | #endif | |
| 1271 | ||
| 1272 | span_constexpr pointer data() const span_noexcept | |
| 1273 | { | |
| 1274 | return data_; | |
| 1275 | } | |
| 1276 | ||
| 1277 | #if span_FEATURE( MEMBER_BACK_FRONT ) | |
| 1278 | ||
| 1279 | span_constexpr_exp reference front() const span_noexcept | |
| 1280 | { | |
| 1281 | span_EXPECTS( ! empty() ); | |
| 1282 | ||
| 1283 | return *data(); | |
| 1284 | } | |
| 1285 | ||
| 1286 | span_constexpr_exp reference back() const span_noexcept | |
| 1287 | { | |
| 1288 | span_EXPECTS( ! empty() ); | |
| 1289 | ||
| 1290 | return *( data() + size() - 1 ); | |
| 1291 | } | |
| 1292 | ||
| 1293 | #endif | |
| 1294 | ||
| 1295 | // xx.x.x.x Modifiers [span.modifiers] | |
| 1296 | ||
| 1297 | #if span_FEATURE( MEMBER_SWAP ) | |
| 1298 | ||
| 1299 | span_constexpr14 void swap( span & other ) span_noexcept | |
| 1300 | { | |
| 1301 | using std::swap; | |
| 1302 | swap( data_, other.data_ ); | |
| 1303 | swap( size_, other.size_ ); | |
| 1304 | } | |
| 1305 | #endif | |
| 1306 | ||
| 1307 | // 26.7.3.6 Iterator support [span.iterators] | |
| 1308 | ||
| 1309 | span_constexpr iterator begin() const span_noexcept | |
| 1310 | { | |
| 1311 | #if span_CPP11_OR_GREATER | |
| 1312 | return { data() }; | |
| 1313 | #else | |
| 1314 | return iterator( data() ); | |
| 1315 | #endif | |
| 1316 | } | |
| 1317 | ||
| 1318 | span_constexpr iterator end() const span_noexcept | |
| 1319 | { | |
| 1320 | #if span_CPP11_OR_GREATER | |
| 1321 | return { data() + size() }; | |
| 1322 | #else | |
| 1323 | return iterator( data() + size() ); | |
| 1324 | #endif | |
| 1325 | } | |
| 1326 | ||
| 1327 | span_constexpr const_iterator cbegin() const span_noexcept | |
| 1328 | { | |
| 1329 | #if span_CPP11_OR_GREATER | |
| 1330 | return { data() }; | |
| 1331 | #else | |
| 1332 | return const_iterator( data() ); | |
| 1333 | #endif | |
| 1334 | } | |
| 1335 | ||
| 1336 | span_constexpr const_iterator cend() const span_noexcept | |
| 1337 | { | |
| 1338 | #if span_CPP11_OR_GREATER | |
| 1339 | return { data() + size() }; | |
| 1340 | #else | |
| 1341 | return const_iterator( data() + size() ); | |
| 1342 | #endif | |
| 1343 | } | |
| 1344 | ||
| 1345 | span_constexpr reverse_iterator rbegin() const span_noexcept | |
| 1346 | { | |
| 1347 | return reverse_iterator( end() ); | |
| 1348 | } | |
| 1349 | ||
| 1350 | span_constexpr reverse_iterator rend() const span_noexcept | |
| 1351 | { | |
| 1352 | return reverse_iterator( begin() ); | |
| 1353 | } | |
| 1354 | ||
| 1355 | span_constexpr const_reverse_iterator crbegin() const span_noexcept | |
| 1356 | { | |
| 1357 | return const_reverse_iterator ( cend() ); | |
| 1358 | } | |
| 1359 | ||
| 1360 | span_constexpr const_reverse_iterator crend() const span_noexcept | |
| 1361 | { | |
| 1362 | return const_reverse_iterator( cbegin() ); | |
| 1363 | } | |
| 1364 | ||
| 1365 | private: | |
| 1366 | ||
| 1367 | // Note: C++20 has std::pointer_traits<Ptr>::to_address( it ); | |
| 1368 | ||
| 1369 | #if span_HAVE( ITERATOR_CTOR ) | |
| 1370 | static inline span_constexpr pointer to_address( std::nullptr_t ) span_noexcept | |
| 1371 | { | |
| 1372 | return nullptr; | |
| 1373 | } | |
| 1374 | ||
| 1375 | template< typename U > | |
| 1376 | static inline span_constexpr U * to_address( U * p ) span_noexcept | |
| 1377 | { | |
| 1378 | return p; | |
| 1379 | } | |
| 1380 | ||
| 1381 | template< typename Ptr | |
| 1382 | span_REQUIRES_T(( ! std::is_pointer<Ptr>::value )) | |
| 1383 | > | |
| 1384 | static inline span_constexpr pointer to_address( Ptr const & it ) span_noexcept | |
| 1385 | { | |
| 1386 | return to_address( it.operator->() ); | |
| 1387 | } | |
| 1388 | #endif // span_HAVE( ITERATOR_CTOR ) | |
| 1389 | ||
| 1390 | private: | |
| 1391 | pointer data_; | |
| 1392 | size_type size_; | |
| 1393 | }; | |
| 1394 | ||
| 1395 | // class template argument deduction guides: | |
| 1396 | ||
| 1397 | #if span_HAVE( DEDUCTION_GUIDES ) | |
| 1398 | ||
| 1399 | template< class T, size_t N > | |
| 1400 | span( T (&)[N] ) -> span<T, static_cast<extent_t>(N)>; | |
| 1401 | ||
| 1402 | template< class T, size_t N > | |
| 1403 | span( std::array<T, N> & ) -> span<T, static_cast<extent_t>(N)>; | |
| 1404 | ||
| 1405 | template< class T, size_t N > | |
| 1406 | span( std::array<T, N> const & ) -> span<const T, static_cast<extent_t>(N)>; | |
| 1407 | ||
| 1408 | #if span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) | |
| 1409 | ||
| 1410 | template< class Container > | |
| 1411 | span( Container& ) -> span<typename Container::value_type>; | |
| 1412 | ||
| 1413 | template< class Container > | |
| 1414 | span( Container const & ) -> span<const typename Container::value_type>; | |
| 1415 | ||
| 1416 | #endif | |
| 1417 | ||
| 1418 | // iterator: constraints: It satisfies contiguous_Âiterator. | |
| 1419 | ||
| 1420 | template< class It, class EndOrSize > | |
| 1421 | span( It, EndOrSize ) -> span< typename std11::remove_reference< typename std20::iter_reference_t<It> >::type >; | |
| 1422 | ||
| 1423 | #endif // span_HAVE( DEDUCTION_GUIDES ) | |
| 1424 | ||
| 1425 | // 26.7.3.7 Comparison operators [span.comparison] | |
| 1426 | ||
| 1427 | #if span_FEATURE( COMPARISON ) | |
| 1428 | #if span_FEATURE( SAME ) | |
| 1429 | ||
| 1430 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1431 | inline span_constexpr bool same( span<T1,E1> const & l, span<T2,E2> const & r ) span_noexcept | |
| 1432 | { | |
| 1433 | return std11::is_same<T1, T2>::value | |
| 1434 | && l.size() == r.size() | |
| 1435 | && static_cast<void const*>( l.data() ) == r.data(); | |
| 1436 | } | |
| 1437 | ||
| 1438 | #endif | |
| 1439 | ||
| 1440 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1441 | inline span_constexpr bool operator==( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1442 | { | |
| 1443 | return | |
| 1444 | #if span_FEATURE( SAME ) | |
| 1445 | same( l, r ) || | |
| 1446 | #endif | |
| 1447 | ( l.size() == r.size() && std::equal( l.begin(), l.end(), r.begin() ) ); | |
| 1448 | } | |
| 1449 | ||
| 1450 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1451 | inline span_constexpr bool operator<( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1452 | { | |
| 1453 | return std::lexicographical_compare( l.begin(), l.end(), r.begin(), r.end() ); | |
| 1454 | } | |
| 1455 | ||
| 1456 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1457 | inline span_constexpr bool operator!=( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1458 | { | |
| 1459 | return !( l == r ); | |
| 1460 | } | |
| 1461 | ||
| 1462 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1463 | inline span_constexpr bool operator<=( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1464 | { | |
| 1465 | return !( r < l ); | |
| 1466 | } | |
| 1467 | ||
| 1468 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1469 | inline span_constexpr bool operator>( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1470 | { | |
| 1471 | return ( r < l ); | |
| 1472 | } | |
| 1473 | ||
| 1474 | template< class T1, extent_t E1, class T2, extent_t E2 > | |
| 1475 | inline span_constexpr bool operator>=( span<T1,E1> const & l, span<T2,E2> const & r ) | |
| 1476 | { | |
| 1477 | return !( l < r ); | |
| 1478 | } | |
| 1479 | ||
| 1480 | #endif // span_FEATURE( COMPARISON ) | |
| 1481 | ||
| 1482 | // 26.7.2.6 views of object representation [span.objectrep] | |
| 1483 | ||
| 1484 | #if span_HAVE( BYTE ) || span_HAVE( NONSTD_BYTE ) | |
| 1485 | ||
| 1486 | // Avoid MSVC 14.1 (1910), VS 2017: warning C4307: '*': integral constant overflow: | |
| 1487 | ||
| 1488 | template< typename T, extent_t Extent > | |
| 1489 | struct BytesExtent | |
| 1490 | { | |
| 1491 | #if span_CPP11_OR_GREATER | |
| 1492 | enum ET : extent_t { value = span_sizeof(T) * Extent }; | |
| 1493 | #else | |
| 1494 | enum ET { value = span_sizeof(T) * Extent }; | |
| 1495 | #endif | |
| 1496 | }; | |
| 1497 | ||
| 1498 | template< typename T > | |
| 1499 | struct BytesExtent< T, dynamic_extent > | |
| 1500 | { | |
| 1501 | #if span_CPP11_OR_GREATER | |
| 1502 | enum ET : extent_t { value = dynamic_extent }; | |
| 1503 | #else | |
| 1504 | enum ET { value = dynamic_extent }; | |
| 1505 | #endif | |
| 1506 | }; | |
| 1507 | ||
| 1508 | template< class T, extent_t Extent > | |
| 1509 | inline span_constexpr span< const std17::byte, BytesExtent<T, Extent>::value > | |
| 1510 | as_bytes( span<T,Extent> spn ) span_noexcept | |
| 1511 | { | |
| 1512 | #if 0 | |
| 1513 | return { reinterpret_cast< std17::byte const * >( spn.data() ), spn.size_bytes() }; | |
| 1514 | #else | |
| 1515 | return span< const std17::byte, BytesExtent<T, Extent>::value >( | |
| 1516 | reinterpret_cast< std17::byte const * >( spn.data() ), spn.size_bytes() ); // NOLINT | |
| 1517 | #endif | |
| 1518 | } | |
| 1519 | ||
| 1520 | template< class T, extent_t Extent > | |
| 1521 | inline span_constexpr span< std17::byte, BytesExtent<T, Extent>::value > | |
| 1522 | as_writable_bytes( span<T,Extent> spn ) span_noexcept | |
| 1523 | { | |
| 1524 | #if 0 | |
| 1525 | return { reinterpret_cast< std17::byte * >( spn.data() ), spn.size_bytes() }; | |
| 1526 | #else | |
| 1527 | return span< std17::byte, BytesExtent<T, Extent>::value >( | |
| 1528 | reinterpret_cast< std17::byte * >( spn.data() ), spn.size_bytes() ); // NOLINT | |
| 1529 | #endif | |
| 1530 | } | |
| 1531 | ||
| 1532 | #endif // span_HAVE( BYTE ) || span_HAVE( NONSTD_BYTE ) | |
| 1533 | ||
| 1534 | // 27.8 Container and view access [iterator.container] | |
| 1535 | ||
| 1536 | template< class T, extent_t Extent /*= dynamic_extent*/ > | |
| 1537 | span_constexpr std::size_t size( span<T,Extent> const & spn ) | |
| 1538 | { | |
| 1539 | return static_cast<std::size_t>( spn.size() ); | |
| 1540 | } | |
| 1541 | ||
| 1542 | template< class T, extent_t Extent /*= dynamic_extent*/ > | |
| 1543 | span_constexpr std::ptrdiff_t ssize( span<T,Extent> const & spn ) | |
| 1544 | { | |
| 1545 | return static_cast<std::ptrdiff_t>( spn.size() ); | |
| 1546 | } | |
| 1547 | ||
| 1548 | } // namespace span_lite | |
| 1549 | } // namespace nonstd | |
| 1550 | ||
| 1551 | // make available in nonstd: | |
| 1552 | ||
| 1553 | namespace nonstd { | |
| 1554 | ||
| 1555 | using span_lite::dynamic_extent; | |
| 1556 | ||
| 1557 | using span_lite::span; | |
| 1558 | ||
| 1559 | using span_lite::with_container; | |
| 1560 | ||
| 1561 | #if span_FEATURE( COMPARISON ) | |
| 1562 | #if span_FEATURE( SAME ) | |
| 1563 | using span_lite::same; | |
| 1564 | #endif | |
| 1565 | ||
| 1566 | using span_lite::operator==; | |
| 1567 | using span_lite::operator!=; | |
| 1568 | using span_lite::operator<; | |
| 1569 | using span_lite::operator<=; | |
| 1570 | using span_lite::operator>; | |
| 1571 | using span_lite::operator>=; | |
| 1572 | #endif | |
| 1573 | ||
| 1574 | #if span_HAVE( BYTE ) | |
| 1575 | using span_lite::as_bytes; | |
| 1576 | using span_lite::as_writable_bytes; | |
| 1577 | #endif | |
| 1578 | ||
| 1579 | using span_lite::size; | |
| 1580 | using span_lite::ssize; | |
| 1581 | ||
| 1582 | } // namespace nonstd | |
| 1583 | ||
| 1584 | #endif // span_USES_STD_SPAN | |
| 1585 | ||
| 1586 | // make_span() [span-lite extension]: | |
| 1587 | ||
| 1588 | #if span_FEATURE( MAKE_SPAN ) || span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_SPAN ) || span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_CONTAINER ) | |
| 1589 | ||
| 1590 | #if span_USES_STD_SPAN | |
| 1591 | # define span_constexpr constexpr | |
| 1592 | # define span_noexcept noexcept | |
| 1593 | # define span_nullptr nullptr | |
| 1594 | # ifndef span_CONFIG_EXTENT_TYPE | |
| 1595 | # define span_CONFIG_EXTENT_TYPE std::size_t | |
| 1596 | # endif | |
| 1597 | using extent_t = span_CONFIG_EXTENT_TYPE; | |
| 1598 | #endif // span_USES_STD_SPAN | |
| 1599 | ||
| 1600 | namespace nonstd { | |
| 1601 | namespace span_lite { | |
| 1602 | ||
| 1603 | template< class T > | |
| 1604 | inline span_constexpr span<T> | |
| 1605 | make_span( T * ptr, size_t count ) span_noexcept | |
| 1606 | { | |
| 1607 | return span<T>( ptr, count ); | |
| 1608 | } | |
| 1609 | ||
| 1610 | template< class T > | |
| 1611 | inline span_constexpr span<T> | |
| 1612 | make_span( T * first, T * last ) span_noexcept | |
| 1613 | { | |
| 1614 | return span<T>( first, last ); | |
| 1615 | } | |
| 1616 | ||
| 1617 | template< class T, std::size_t N > | |
| 1618 | inline span_constexpr span<T, static_cast<extent_t>(N)> | |
| 1619 | make_span( T ( &arr )[ N ] ) span_noexcept | |
| 1620 | { | |
| 1621 | return span<T, static_cast<extent_t>(N)>( &arr[ 0 ], N ); | |
| 1622 | } | |
| 1623 | ||
| 1624 | #if span_USES_STD_SPAN || span_HAVE( ARRAY ) | |
| 1625 | ||
| 1626 | template< class T, std::size_t N > | |
| 1627 | inline span_constexpr span<T, static_cast<extent_t>(N)> | |
| 1628 | make_span( std::array< T, N > & arr ) span_noexcept | |
| 1629 | { | |
| 1630 | return span<T, static_cast<extent_t>(N)>( arr ); | |
| 1631 | } | |
| 1632 | ||
| 1633 | template< class T, std::size_t N > | |
| 1634 | inline span_constexpr span< const T, static_cast<extent_t>(N) > | |
| 1635 | make_span( std::array< T, N > const & arr ) span_noexcept | |
| 1636 | { | |
| 1637 | return span<const T, static_cast<extent_t>(N)>( arr ); | |
| 1638 | } | |
| 1639 | ||
| 1640 | #endif // span_HAVE( ARRAY ) | |
| 1641 | ||
| 1642 | #if span_USES_STD_SPAN || span_HAVE( INITIALIZER_LIST ) | |
| 1643 | ||
| 1644 | template< class T > | |
| 1645 | inline span_constexpr span< const T > | |
| 1646 | make_span( std::initializer_list<T> il ) span_noexcept | |
| 1647 | { | |
| 1648 | return span<const T>( il.begin(), il.size() ); | |
| 1649 | } | |
| 1650 | ||
| 1651 | #endif // span_HAVE( INITIALIZER_LIST ) | |
| 1652 | ||
| 1653 | #if span_USES_STD_SPAN | |
| 1654 | ||
| 1655 | template< class Container, class EP = decltype( std::data(std::declval<Container&>())) > | |
| 1656 | inline span_constexpr auto | |
| 1657 | make_span( Container & cont ) span_noexcept -> span< typename std::remove_pointer<EP>::type > | |
| 1658 | { | |
| 1659 | return span< typename std::remove_pointer<EP>::type >( cont ); | |
| 1660 | } | |
| 1661 | ||
| 1662 | template< class Container, class EP = decltype( std::data(std::declval<Container&>())) > | |
| 1663 | inline span_constexpr auto | |
| 1664 | make_span( Container const & cont ) span_noexcept -> span< const typename std::remove_pointer<EP>::type > | |
| 1665 | { | |
| 1666 | return span< const typename std::remove_pointer<EP>::type >( cont ); | |
| 1667 | } | |
| 1668 | ||
| 1669 | #elif span_HAVE( CONSTRAINED_SPAN_CONTAINER_CTOR ) && span_HAVE( AUTO ) | |
| 1670 | ||
| 1671 | template< class Container, class EP = decltype( std17::data(std::declval<Container&>())) > | |
| 1672 | inline span_constexpr auto | |
| 1673 | make_span( Container & cont ) span_noexcept -> span< typename std::remove_pointer<EP>::type > | |
| 1674 | { | |
| 1675 | return span< typename std::remove_pointer<EP>::type >( cont ); | |
| 1676 | } | |
| 1677 | ||
| 1678 | template< class Container, class EP = decltype( std17::data(std::declval<Container&>())) > | |
| 1679 | inline span_constexpr auto | |
| 1680 | make_span( Container const & cont ) span_noexcept -> span< const typename std::remove_pointer<EP>::type > | |
| 1681 | { | |
| 1682 | return span< const typename std::remove_pointer<EP>::type >( cont ); | |
| 1683 | } | |
| 1684 | ||
| 1685 | #else | |
| 1686 | ||
| 1687 | template< class T > | |
| 1688 | inline span_constexpr span<T> | |
| 1689 | make_span( span<T> spn ) span_noexcept | |
| 1690 | { | |
| 1691 | return spn; | |
| 1692 | } | |
| 1693 | ||
| 1694 | template< class T, class Allocator > | |
| 1695 | inline span_constexpr span<T> | |
| 1696 | make_span( std::vector<T, Allocator> & cont ) span_noexcept | |
| 1697 | { | |
| 1698 | return span<T>( with_container, cont ); | |
| 1699 | } | |
| 1700 | ||
| 1701 | template< class T, class Allocator > | |
| 1702 | inline span_constexpr span<const T> | |
| 1703 | make_span( std::vector<T, Allocator> const & cont ) span_noexcept | |
| 1704 | { | |
| 1705 | return span<const T>( with_container, cont ); | |
| 1706 | } | |
| 1707 | ||
| 1708 | #endif // span_USES_STD_SPAN || ( ... ) | |
| 1709 | ||
| 1710 | #if ! span_USES_STD_SPAN && span_FEATURE( WITH_CONTAINER ) | |
| 1711 | ||
| 1712 | template< class Container > | |
| 1713 | inline span_constexpr span<typename Container::value_type> | |
| 1714 | make_span( with_container_t, Container & cont ) span_noexcept | |
| 1715 | { | |
| 1716 | return span< typename Container::value_type >( with_container, cont ); | |
| 1717 | } | |
| 1718 | ||
| 1719 | template< class Container > | |
| 1720 | inline span_constexpr span<const typename Container::value_type> | |
| 1721 | make_span( with_container_t, Container const & cont ) span_noexcept | |
| 1722 | { | |
| 1723 | return span< const typename Container::value_type >( with_container, cont ); | |
| 1724 | } | |
| 1725 | ||
| 1726 | #endif // ! span_USES_STD_SPAN && span_FEATURE( WITH_CONTAINER ) | |
| 1727 | ||
| 1728 | // extensions: non-member views: | |
| 1729 | // this feature implies the presence of make_span() | |
| 1730 | ||
| 1731 | #if span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_SPAN ) | |
| 1732 | ||
| 1733 | template< extent_t Count, class T, extent_t Extent > | |
| 1734 | span_constexpr span<T, Count> | |
| 1735 | first( span<T, Extent> spn ) | |
| 1736 | { | |
| 1737 | return spn.template first<Count>(); | |
| 1738 | } | |
| 1739 | ||
| 1740 | template< class T, extent_t Extent > | |
| 1741 | span_constexpr span<T> | |
| 1742 | first( span<T, Extent> spn, size_t count ) | |
| 1743 | { | |
| 1744 | return spn.first( count ); | |
| 1745 | } | |
| 1746 | ||
| 1747 | template< extent_t Count, class T, extent_t Extent > | |
| 1748 | span_constexpr span<T, Count> | |
| 1749 | last( span<T, Extent> spn ) | |
| 1750 | { | |
| 1751 | return spn.template last<Count>(); | |
| 1752 | } | |
| 1753 | ||
| 1754 | template< class T, extent_t Extent > | |
| 1755 | span_constexpr span<T> | |
| 1756 | last( span<T, Extent> spn, size_t count ) | |
| 1757 | { | |
| 1758 | return spn.last( count ); | |
| 1759 | } | |
| 1760 | ||
| 1761 | template< size_t Offset, extent_t Count, class T, extent_t Extent > | |
| 1762 | span_constexpr span<T, Count> | |
| 1763 | subspan( span<T, Extent> spn ) | |
| 1764 | { | |
| 1765 | return spn.template subspan<Offset, Count>(); | |
| 1766 | } | |
| 1767 | ||
| 1768 | template< class T, extent_t Extent > | |
| 1769 | span_constexpr span<T> | |
| 1770 | subspan( span<T, Extent> spn, size_t offset, extent_t count = dynamic_extent ) | |
| 1771 | { | |
| 1772 | return spn.subspan( offset, count ); | |
| 1773 | } | |
| 1774 | ||
| 1775 | #endif // span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_SPAN ) | |
| 1776 | ||
| 1777 | #if span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_CONTAINER ) && span_CPP11_120 | |
| 1778 | ||
| 1779 | template< extent_t Count, class T > | |
| 1780 | span_constexpr auto | |
| 1781 | first( T & t ) -> decltype( make_span(t).template first<Count>() ) | |
| 1782 | { | |
| 1783 | return make_span( t ).template first<Count>(); | |
| 1784 | } | |
| 1785 | ||
| 1786 | template< class T > | |
| 1787 | span_constexpr auto | |
| 1788 | first( T & t, size_t count ) -> decltype( make_span(t).first(count) ) | |
| 1789 | { | |
| 1790 | return make_span( t ).first( count ); | |
| 1791 | } | |
| 1792 | ||
| 1793 | template< extent_t Count, class T > | |
| 1794 | span_constexpr auto | |
| 1795 | last( T & t ) -> decltype( make_span(t).template last<Count>() ) | |
| 1796 | { | |
| 1797 | return make_span(t).template last<Count>(); | |
| 1798 | } | |
| 1799 | ||
| 1800 | template< class T > | |
| 1801 | span_constexpr auto | |
| 1802 | last( T & t, extent_t count ) -> decltype( make_span(t).last(count) ) | |
| 1803 | { | |
| 1804 | return make_span( t ).last( count ); | |
| 1805 | } | |
| 1806 | ||
| 1807 | template< size_t Offset, extent_t Count = dynamic_extent, class T > | |
| 1808 | span_constexpr auto | |
| 1809 | subspan( T & t ) -> decltype( make_span(t).template subspan<Offset, Count>() ) | |
| 1810 | { | |
| 1811 | return make_span( t ).template subspan<Offset, Count>(); | |
| 1812 | } | |
| 1813 | ||
| 1814 | template< class T > | |
| 1815 | span_constexpr auto | |
| 1816 | subspan( T & t, size_t offset, extent_t count = dynamic_extent ) -> decltype( make_span(t).subspan(offset, count) ) | |
| 1817 | { | |
| 1818 | return make_span( t ).subspan( offset, count ); | |
| 1819 | } | |
| 1820 | ||
| 1821 | #endif // span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_CONTAINER ) | |
| 1822 | ||
| 1823 | } // namespace span_lite | |
| 1824 | } // namespace nonstd | |
| 1825 | ||
| 1826 | // make available in nonstd: | |
| 1827 | ||
| 1828 | namespace nonstd { | |
| 1829 | using span_lite::make_span; | |
| 1830 | ||
| 1831 | #if span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_SPAN ) || ( span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_CONTAINER ) && span_CPP11_120 ) | |
| 1832 | ||
| 1833 | using span_lite::first; | |
| 1834 | using span_lite::last; | |
| 1835 | using span_lite::subspan; | |
| 1836 | ||
| 1837 | #endif // span_FEATURE( NON_MEMBER_FIRST_LAST_SUB_[SPAN|CONTAINER] ) | |
| 1838 | ||
| 1839 | } // namespace nonstd | |
| 1840 | ||
| 1841 | #endif // #if span_FEATURE_TO_STD( MAKE_SPAN ) | |
| 1842 | ||
| 1843 | #if span_CPP11_OR_GREATER && span_FEATURE( BYTE_SPAN ) && ( span_HAVE( BYTE ) || span_HAVE( NONSTD_BYTE ) ) | |
| 1844 | ||
| 1845 | namespace nonstd { | |
| 1846 | namespace span_lite { | |
| 1847 | ||
| 1848 | template< class T > | |
| 1849 | inline span_constexpr auto | |
| 1850 | byte_span( T & t ) span_noexcept -> span< std17::byte, span_sizeof(T) > | |
| 1851 | { | |
| 1852 | return span< std17::byte, span_sizeof(t) >( reinterpret_cast< std17::byte * >( &t ), span_sizeof(T) ); | |
| 1853 | } | |
| 1854 | ||
| 1855 | template< class T > | |
| 1856 | inline span_constexpr auto | |
| 1857 | byte_span( T const & t ) span_noexcept -> span< const std17::byte, span_sizeof(T) > | |
| 1858 | { | |
| 1859 | return span< const std17::byte, span_sizeof(t) >( reinterpret_cast< std17::byte const * >( &t ), span_sizeof(T) ); | |
| 1860 | } | |
| 1861 | ||
| 1862 | } // namespace span_lite | |
| 1863 | } // namespace nonstd | |
| 1864 | ||
| 1865 | // make available in nonstd: | |
| 1866 | ||
| 1867 | namespace nonstd { | |
| 1868 | using span_lite::byte_span; | |
| 1869 | } // namespace nonstd | |
| 1870 | ||
| 1871 | #endif // span_FEATURE( BYTE_SPAN ) | |
| 1872 | ||
| f90b6191 | 1873 | #if !span_USES_STD_SPAN && span_HAVE( STRUCT_BINDING ) |
| 30586bf0 PP |
1874 | |
| 1875 | #if span_CPP14_OR_GREATER | |
| 1876 | # include <tuple> | |
| 1877 | #elif span_CPP11_OR_GREATER | |
| 1878 | # include <tuple> | |
| 1879 | namespace std { | |
| 1880 | template< std::size_t I, typename T > | |
| 1881 | using tuple_element_t = typename tuple_element<I, T>::type; | |
| 1882 | } | |
| 1883 | #else | |
| 1884 | namespace std { | |
| 1885 | template< typename T > | |
| 1886 | class tuple_size; /*undefined*/ | |
| 1887 | ||
| 1888 | template< std::size_t I, typename T > | |
| 1889 | class tuple_element; /* undefined */ | |
| 1890 | } | |
| 1891 | #endif // span_CPP14_OR_GREATER | |
| 1892 | ||
| 1893 | namespace std { | |
| 1894 | ||
| 1895 | // 26.7.X Tuple interface | |
| 1896 | ||
| 1897 | // std::tuple_size<>: | |
| 1898 | ||
| 1899 | template< typename ElementType, nonstd::span_lite::extent_t Extent > | |
| 1900 | class tuple_size< nonstd::span<ElementType, Extent> > : public integral_constant<size_t, static_cast<size_t>(Extent)> {}; | |
| 1901 | ||
| 1902 | // std::tuple_size<>: Leave undefined for dynamic extent: | |
| 1903 | ||
| 1904 | template< typename ElementType > | |
| 1905 | class tuple_size< nonstd::span<ElementType, nonstd::dynamic_extent> >; | |
| 1906 | ||
| 1907 | // std::tuple_element<>: | |
| 1908 | ||
| 1909 | template< size_t I, typename ElementType, nonstd::span_lite::extent_t Extent > | |
| 1910 | class tuple_element< I, nonstd::span<ElementType, Extent> > | |
| 1911 | { | |
| 1912 | public: | |
| 1913 | #if span_HAVE( STATIC_ASSERT ) | |
| 1914 | static_assert( Extent != nonstd::dynamic_extent && I < Extent, "tuple_element<I,span>: dynamic extent or index out of range" ); | |
| 1915 | #endif | |
| 1916 | using type = ElementType; | |
| 1917 | }; | |
| 1918 | ||
| 1919 | // std::get<>(), 2 variants: | |
| 1920 | ||
| 1921 | template< size_t I, typename ElementType, nonstd::span_lite::extent_t Extent > | |
| 1922 | span_constexpr ElementType & get( nonstd::span<ElementType, Extent> & spn ) span_noexcept | |
| 1923 | { | |
| 1924 | #if span_HAVE( STATIC_ASSERT ) | |
| 1925 | static_assert( Extent != nonstd::dynamic_extent && I < Extent, "get<>(span): dynamic extent or index out of range" ); | |
| 1926 | #endif | |
| 1927 | return spn[I]; | |
| 1928 | } | |
| 1929 | ||
| 1930 | template< size_t I, typename ElementType, nonstd::span_lite::extent_t Extent > | |
| 1931 | span_constexpr ElementType const & get( nonstd::span<ElementType, Extent> const & spn ) span_noexcept | |
| 1932 | { | |
| 1933 | #if span_HAVE( STATIC_ASSERT ) | |
| 1934 | static_assert( Extent != nonstd::dynamic_extent && I < Extent, "get<>(span): dynamic extent or index out of range" ); | |
| 1935 | #endif | |
| 1936 | return spn[I]; | |
| 1937 | } | |
| 1938 | ||
| 1939 | } // end namespace std | |
| 1940 | ||
| f90b6191 | 1941 | #endif // !span_USES_STD_SPAN && span_HAVE( STRUCT_BINDING ) |
| 30586bf0 PP |
1942 | |
| 1943 | #if ! span_USES_STD_SPAN | |
| 1944 | span_RESTORE_WARNINGS() | |
| 1945 | #endif // span_USES_STD_SPAN | |
| 1946 | ||
| 1947 | #endif // NONSTD_SPAN_HPP_INCLUDED |