| 1 | // Formatting library for C++ - range and tuple support |
| 2 | // |
| 3 | // Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors |
| 4 | // All rights reserved. |
| 5 | // |
| 6 | // For the license information refer to format.h. |
| 7 | |
| 8 | #ifndef FMT_RANGES_H_ |
| 9 | #define FMT_RANGES_H_ |
| 10 | |
| 11 | #ifndef FMT_MODULE |
| 12 | # include <initializer_list> |
| 13 | # include <iterator> |
| 14 | # include <string> |
| 15 | # include <tuple> |
| 16 | # include <type_traits> |
| 17 | # include <utility> |
| 18 | #endif |
| 19 | |
| 20 | #include "format.h" |
| 21 | |
| 22 | FMT_BEGIN_NAMESPACE |
| 23 | |
| 24 | FMT_EXPORT |
| 25 | enum class range_format { disabled, map, set, sequence, string, debug_string }; |
| 26 | |
| 27 | namespace detail { |
| 28 | |
| 29 | template <typename T> class is_map { |
| 30 | template <typename U> static auto check(U*) -> typename U::mapped_type; |
| 31 | template <typename> static void check(...); |
| 32 | |
| 33 | public: |
| 34 | static constexpr const bool value = |
| 35 | !std::is_void<decltype(check<T>(nullptr))>::value; |
| 36 | }; |
| 37 | |
| 38 | template <typename T> class is_set { |
| 39 | template <typename U> static auto check(U*) -> typename U::key_type; |
| 40 | template <typename> static void check(...); |
| 41 | |
| 42 | public: |
| 43 | static constexpr const bool value = |
| 44 | !std::is_void<decltype(check<T>(nullptr))>::value && !is_map<T>::value; |
| 45 | }; |
| 46 | |
| 47 | template <typename... Ts> struct conditional_helper {}; |
| 48 | |
| 49 | template <typename T, typename _ = void> struct is_range_ : std::false_type {}; |
| 50 | |
| 51 | #if !FMT_MSC_VERSION || FMT_MSC_VERSION > 1800 |
| 52 | |
| 53 | # define FMT_DECLTYPE_RETURN(val) \ |
| 54 | ->decltype(val) { return val; } \ |
| 55 | static_assert( \ |
| 56 | true, "") // This makes it so that a semicolon is required after the |
| 57 | // macro, which helps clang-format handle the formatting. |
| 58 | |
| 59 | // C array overload |
| 60 | template <typename T, std::size_t N> |
| 61 | auto range_begin(const T (&arr)[N]) -> const T* { |
| 62 | return arr; |
| 63 | } |
| 64 | template <typename T, std::size_t N> |
| 65 | auto range_end(const T (&arr)[N]) -> const T* { |
| 66 | return arr + N; |
| 67 | } |
| 68 | |
| 69 | template <typename T, typename Enable = void> |
| 70 | struct has_member_fn_begin_end_t : std::false_type {}; |
| 71 | |
| 72 | template <typename T> |
| 73 | struct has_member_fn_begin_end_t<T, void_t<decltype(*std::declval<T>().begin()), |
| 74 | decltype(std::declval<T>().end())>> |
| 75 | : std::true_type {}; |
| 76 | |
| 77 | // Member function overloads. |
| 78 | template <typename T> |
| 79 | auto range_begin(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).begin()); |
| 80 | template <typename T> |
| 81 | auto range_end(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).end()); |
| 82 | |
| 83 | // ADL overloads. Only participate in overload resolution if member functions |
| 84 | // are not found. |
| 85 | template <typename T> |
| 86 | auto range_begin(T&& rng) |
| 87 | -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value, |
| 88 | decltype(begin(static_cast<T&&>(rng)))> { |
| 89 | return begin(static_cast<T&&>(rng)); |
| 90 | } |
| 91 | template <typename T> |
| 92 | auto range_end(T&& rng) -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value, |
| 93 | decltype(end(static_cast<T&&>(rng)))> { |
| 94 | return end(static_cast<T&&>(rng)); |
| 95 | } |
| 96 | |
| 97 | template <typename T, typename Enable = void> |
| 98 | struct has_const_begin_end : std::false_type {}; |
| 99 | template <typename T, typename Enable = void> |
| 100 | struct has_mutable_begin_end : std::false_type {}; |
| 101 | |
| 102 | template <typename T> |
| 103 | struct has_const_begin_end< |
| 104 | T, void_t<decltype(*detail::range_begin( |
| 105 | std::declval<const remove_cvref_t<T>&>())), |
| 106 | decltype(detail::range_end( |
| 107 | std::declval<const remove_cvref_t<T>&>()))>> |
| 108 | : std::true_type {}; |
| 109 | |
| 110 | template <typename T> |
| 111 | struct has_mutable_begin_end< |
| 112 | T, void_t<decltype(*detail::range_begin(std::declval<T&>())), |
| 113 | decltype(detail::range_end(std::declval<T&>())), |
| 114 | // the extra int here is because older versions of MSVC don't |
| 115 | // SFINAE properly unless there are distinct types |
| 116 | int>> : std::true_type {}; |
| 117 | |
| 118 | template <typename T> |
| 119 | struct is_range_<T, void> |
| 120 | : std::integral_constant<bool, (has_const_begin_end<T>::value || |
| 121 | has_mutable_begin_end<T>::value)> {}; |
| 122 | # undef FMT_DECLTYPE_RETURN |
| 123 | #endif |
| 124 | |
| 125 | // tuple_size and tuple_element check. |
| 126 | template <typename T> class is_tuple_like_ { |
| 127 | template <typename U> |
| 128 | static auto check(U* p) -> decltype(std::tuple_size<U>::value, int()); |
| 129 | template <typename> static void check(...); |
| 130 | |
| 131 | public: |
| 132 | static constexpr const bool value = |
| 133 | !std::is_void<decltype(check<T>(nullptr))>::value; |
| 134 | }; |
| 135 | |
| 136 | // Check for integer_sequence |
| 137 | #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VERSION >= 1900 |
| 138 | template <typename T, T... N> |
| 139 | using integer_sequence = std::integer_sequence<T, N...>; |
| 140 | template <size_t... N> using index_sequence = std::index_sequence<N...>; |
| 141 | template <size_t N> using make_index_sequence = std::make_index_sequence<N>; |
| 142 | #else |
| 143 | template <typename T, T... N> struct integer_sequence { |
| 144 | using value_type = T; |
| 145 | |
| 146 | static FMT_CONSTEXPR auto size() -> size_t { return sizeof...(N); } |
| 147 | }; |
| 148 | |
| 149 | template <size_t... N> using index_sequence = integer_sequence<size_t, N...>; |
| 150 | |
| 151 | template <typename T, size_t N, T... Ns> |
| 152 | struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {}; |
| 153 | template <typename T, T... Ns> |
| 154 | struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {}; |
| 155 | |
| 156 | template <size_t N> |
| 157 | using make_index_sequence = make_integer_sequence<size_t, N>; |
| 158 | #endif |
| 159 | |
| 160 | template <typename T> |
| 161 | using tuple_index_sequence = make_index_sequence<std::tuple_size<T>::value>; |
| 162 | |
| 163 | template <typename T, typename C, bool = is_tuple_like_<T>::value> |
| 164 | class is_tuple_formattable_ { |
| 165 | public: |
| 166 | static constexpr const bool value = false; |
| 167 | }; |
| 168 | template <typename T, typename C> class is_tuple_formattable_<T, C, true> { |
| 169 | template <size_t... Is> |
| 170 | static auto all_true(index_sequence<Is...>, |
| 171 | integer_sequence<bool, (Is >= 0)...>) -> std::true_type; |
| 172 | static auto all_true(...) -> std::false_type; |
| 173 | |
| 174 | template <size_t... Is> |
| 175 | static auto check(index_sequence<Is...>) -> decltype(all_true( |
| 176 | index_sequence<Is...>{}, |
| 177 | integer_sequence<bool, |
| 178 | (is_formattable<typename std::tuple_element<Is, T>::type, |
| 179 | C>::value)...>{})); |
| 180 | |
| 181 | public: |
| 182 | static constexpr const bool value = |
| 183 | decltype(check(tuple_index_sequence<T>{}))::value; |
| 184 | }; |
| 185 | |
| 186 | template <typename Tuple, typename F, size_t... Is> |
| 187 | FMT_CONSTEXPR void for_each(index_sequence<Is...>, Tuple&& t, F&& f) { |
| 188 | using std::get; |
| 189 | // Using a free function get<Is>(Tuple) now. |
| 190 | const int unused[] = {0, ((void)f(get<Is>(t)), 0)...}; |
| 191 | ignore_unused(unused); |
| 192 | } |
| 193 | |
| 194 | template <typename Tuple, typename F> |
| 195 | FMT_CONSTEXPR void for_each(Tuple&& t, F&& f) { |
| 196 | for_each(tuple_index_sequence<remove_cvref_t<Tuple>>(), |
| 197 | std::forward<Tuple>(t), std::forward<F>(f)); |
| 198 | } |
| 199 | |
| 200 | template <typename Tuple1, typename Tuple2, typename F, size_t... Is> |
| 201 | void for_each2(index_sequence<Is...>, Tuple1&& t1, Tuple2&& t2, F&& f) { |
| 202 | using std::get; |
| 203 | const int unused[] = {0, ((void)f(get<Is>(t1), get<Is>(t2)), 0)...}; |
| 204 | ignore_unused(unused); |
| 205 | } |
| 206 | |
| 207 | template <typename Tuple1, typename Tuple2, typename F> |
| 208 | void for_each2(Tuple1&& t1, Tuple2&& t2, F&& f) { |
| 209 | for_each2(tuple_index_sequence<remove_cvref_t<Tuple1>>(), |
| 210 | std::forward<Tuple1>(t1), std::forward<Tuple2>(t2), |
| 211 | std::forward<F>(f)); |
| 212 | } |
| 213 | |
| 214 | namespace tuple { |
| 215 | // Workaround a bug in MSVC 2019 (v140). |
| 216 | template <typename Char, typename... T> |
| 217 | using result_t = std::tuple<formatter<remove_cvref_t<T>, Char>...>; |
| 218 | |
| 219 | using std::get; |
| 220 | template <typename Tuple, typename Char, std::size_t... Is> |
| 221 | auto get_formatters(index_sequence<Is...>) |
| 222 | -> result_t<Char, decltype(get<Is>(std::declval<Tuple>()))...>; |
| 223 | } // namespace tuple |
| 224 | |
| 225 | #if FMT_MSC_VERSION && FMT_MSC_VERSION < 1920 |
| 226 | // Older MSVC doesn't get the reference type correctly for arrays. |
| 227 | template <typename R> struct range_reference_type_impl { |
| 228 | using type = decltype(*detail::range_begin(std::declval<R&>())); |
| 229 | }; |
| 230 | |
| 231 | template <typename T, std::size_t N> struct range_reference_type_impl<T[N]> { |
| 232 | using type = T&; |
| 233 | }; |
| 234 | |
| 235 | template <typename T> |
| 236 | using range_reference_type = typename range_reference_type_impl<T>::type; |
| 237 | #else |
| 238 | template <typename Range> |
| 239 | using range_reference_type = |
| 240 | decltype(*detail::range_begin(std::declval<Range&>())); |
| 241 | #endif |
| 242 | |
| 243 | // We don't use the Range's value_type for anything, but we do need the Range's |
| 244 | // reference type, with cv-ref stripped. |
| 245 | template <typename Range> |
| 246 | using uncvref_type = remove_cvref_t<range_reference_type<Range>>; |
| 247 | |
| 248 | template <typename Formatter> |
| 249 | FMT_CONSTEXPR auto maybe_set_debug_format(Formatter& f, bool set) |
| 250 | -> decltype(f.set_debug_format(set)) { |
| 251 | f.set_debug_format(set); |
| 252 | } |
| 253 | template <typename Formatter> |
| 254 | FMT_CONSTEXPR void maybe_set_debug_format(Formatter&, ...) {} |
| 255 | |
| 256 | template <typename T> |
| 257 | struct range_format_kind_ |
| 258 | : std::integral_constant<range_format, |
| 259 | std::is_same<uncvref_type<T>, T>::value |
| 260 | ? range_format::disabled |
| 261 | : is_map<T>::value ? range_format::map |
| 262 | : is_set<T>::value ? range_format::set |
| 263 | : range_format::sequence> {}; |
| 264 | |
| 265 | template <range_format K> |
| 266 | using range_format_constant = std::integral_constant<range_format, K>; |
| 267 | |
| 268 | // These are not generic lambdas for compatibility with C++11. |
| 269 | template <typename ParseContext> struct parse_empty_specs { |
| 270 | template <typename Formatter> FMT_CONSTEXPR void operator()(Formatter& f) { |
| 271 | f.parse(ctx); |
| 272 | detail::maybe_set_debug_format(f, true); |
| 273 | } |
| 274 | ParseContext& ctx; |
| 275 | }; |
| 276 | template <typename FormatContext> struct format_tuple_element { |
| 277 | using char_type = typename FormatContext::char_type; |
| 278 | |
| 279 | template <typename T> |
| 280 | void operator()(const formatter<T, char_type>& f, const T& v) { |
| 281 | if (i > 0) ctx.advance_to(detail::copy<char_type>(separator, ctx.out())); |
| 282 | ctx.advance_to(f.format(v, ctx)); |
| 283 | ++i; |
| 284 | } |
| 285 | |
| 286 | int i; |
| 287 | FormatContext& ctx; |
| 288 | basic_string_view<char_type> separator; |
| 289 | }; |
| 290 | |
| 291 | } // namespace detail |
| 292 | |
| 293 | template <typename T> struct is_tuple_like { |
| 294 | static constexpr const bool value = |
| 295 | detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value; |
| 296 | }; |
| 297 | |
| 298 | template <typename T, typename C> struct is_tuple_formattable { |
| 299 | static constexpr const bool value = |
| 300 | detail::is_tuple_formattable_<T, C>::value; |
| 301 | }; |
| 302 | |
| 303 | template <typename Tuple, typename Char> |
| 304 | struct formatter<Tuple, Char, |
| 305 | enable_if_t<fmt::is_tuple_like<Tuple>::value && |
| 306 | fmt::is_tuple_formattable<Tuple, Char>::value>> { |
| 307 | private: |
| 308 | decltype(detail::tuple::get_formatters<Tuple, Char>( |
| 309 | detail::tuple_index_sequence<Tuple>())) formatters_; |
| 310 | |
| 311 | basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{}; |
| 312 | basic_string_view<Char> opening_bracket_ = |
| 313 | detail::string_literal<Char, '('>{}; |
| 314 | basic_string_view<Char> closing_bracket_ = |
| 315 | detail::string_literal<Char, ')'>{}; |
| 316 | |
| 317 | public: |
| 318 | FMT_CONSTEXPR formatter() {} |
| 319 | |
| 320 | FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) { |
| 321 | separator_ = sep; |
| 322 | } |
| 323 | |
| 324 | FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open, |
| 325 | basic_string_view<Char> close) { |
| 326 | opening_bracket_ = open; |
| 327 | closing_bracket_ = close; |
| 328 | } |
| 329 | |
| 330 | template <typename ParseContext> |
| 331 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 332 | auto it = ctx.begin(); |
| 333 | if (it != ctx.end() && *it != '}') report_error("invalid format specifier"); |
| 334 | detail::for_each(formatters_, detail::parse_empty_specs<ParseContext>{ctx}); |
| 335 | return it; |
| 336 | } |
| 337 | |
| 338 | template <typename FormatContext> |
| 339 | auto format(const Tuple& value, FormatContext& ctx) const |
| 340 | -> decltype(ctx.out()) { |
| 341 | ctx.advance_to(detail::copy<Char>(opening_bracket_, ctx.out())); |
| 342 | detail::for_each2( |
| 343 | formatters_, value, |
| 344 | detail::format_tuple_element<FormatContext>{0, ctx, separator_}); |
| 345 | return detail::copy<Char>(closing_bracket_, ctx.out()); |
| 346 | } |
| 347 | }; |
| 348 | |
| 349 | template <typename T, typename Char> struct is_range { |
| 350 | static constexpr const bool value = |
| 351 | detail::is_range_<T>::value && !detail::has_to_string_view<T>::value; |
| 352 | }; |
| 353 | |
| 354 | namespace detail { |
| 355 | template <typename Context> struct range_mapper { |
| 356 | using mapper = arg_mapper<Context>; |
| 357 | |
| 358 | template <typename T, |
| 359 | FMT_ENABLE_IF(has_formatter<remove_cvref_t<T>, Context>::value)> |
| 360 | static auto map(T&& value) -> T&& { |
| 361 | return static_cast<T&&>(value); |
| 362 | } |
| 363 | template <typename T, |
| 364 | FMT_ENABLE_IF(!has_formatter<remove_cvref_t<T>, Context>::value)> |
| 365 | static auto map(T&& value) |
| 366 | -> decltype(mapper().map(static_cast<T&&>(value))) { |
| 367 | return mapper().map(static_cast<T&&>(value)); |
| 368 | } |
| 369 | }; |
| 370 | |
| 371 | template <typename Char, typename Element> |
| 372 | using range_formatter_type = |
| 373 | formatter<remove_cvref_t<decltype(range_mapper<buffered_context<Char>>{} |
| 374 | .map(std::declval<Element>()))>, |
| 375 | Char>; |
| 376 | |
| 377 | template <typename R> |
| 378 | using maybe_const_range = |
| 379 | conditional_t<has_const_begin_end<R>::value, const R, R>; |
| 380 | |
| 381 | // Workaround a bug in MSVC 2015 and earlier. |
| 382 | #if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910 |
| 383 | template <typename R, typename Char> |
| 384 | struct is_formattable_delayed |
| 385 | : is_formattable<uncvref_type<maybe_const_range<R>>, Char> {}; |
| 386 | #endif |
| 387 | } // namespace detail |
| 388 | |
| 389 | template <typename...> struct conjunction : std::true_type {}; |
| 390 | template <typename P> struct conjunction<P> : P {}; |
| 391 | template <typename P1, typename... Pn> |
| 392 | struct conjunction<P1, Pn...> |
| 393 | : conditional_t<bool(P1::value), conjunction<Pn...>, P1> {}; |
| 394 | |
| 395 | template <typename T, typename Char, typename Enable = void> |
| 396 | struct range_formatter; |
| 397 | |
| 398 | template <typename T, typename Char> |
| 399 | struct range_formatter< |
| 400 | T, Char, |
| 401 | enable_if_t<conjunction<std::is_same<T, remove_cvref_t<T>>, |
| 402 | is_formattable<T, Char>>::value>> { |
| 403 | private: |
| 404 | detail::range_formatter_type<Char, T> underlying_; |
| 405 | basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{}; |
| 406 | basic_string_view<Char> opening_bracket_ = |
| 407 | detail::string_literal<Char, '['>{}; |
| 408 | basic_string_view<Char> closing_bracket_ = |
| 409 | detail::string_literal<Char, ']'>{}; |
| 410 | bool is_debug = false; |
| 411 | |
| 412 | template <typename Output, typename It, typename Sentinel, typename U = T, |
| 413 | FMT_ENABLE_IF(std::is_same<U, Char>::value)> |
| 414 | auto write_debug_string(Output& out, It it, Sentinel end) const -> Output { |
| 415 | auto buf = basic_memory_buffer<Char>(); |
| 416 | for (; it != end; ++it) buf.push_back(*it); |
| 417 | auto specs = format_specs(); |
| 418 | specs.type = presentation_type::debug; |
| 419 | return detail::write<Char>( |
| 420 | out, basic_string_view<Char>(buf.data(), buf.size()), specs); |
| 421 | } |
| 422 | |
| 423 | template <typename Output, typename It, typename Sentinel, typename U = T, |
| 424 | FMT_ENABLE_IF(!std::is_same<U, Char>::value)> |
| 425 | auto write_debug_string(Output& out, It, Sentinel) const -> Output { |
| 426 | return out; |
| 427 | } |
| 428 | |
| 429 | public: |
| 430 | FMT_CONSTEXPR range_formatter() {} |
| 431 | |
| 432 | FMT_CONSTEXPR auto underlying() -> detail::range_formatter_type<Char, T>& { |
| 433 | return underlying_; |
| 434 | } |
| 435 | |
| 436 | FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) { |
| 437 | separator_ = sep; |
| 438 | } |
| 439 | |
| 440 | FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open, |
| 441 | basic_string_view<Char> close) { |
| 442 | opening_bracket_ = open; |
| 443 | closing_bracket_ = close; |
| 444 | } |
| 445 | |
| 446 | template <typename ParseContext> |
| 447 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 448 | auto it = ctx.begin(); |
| 449 | auto end = ctx.end(); |
| 450 | detail::maybe_set_debug_format(underlying_, true); |
| 451 | if (it == end) return underlying_.parse(ctx); |
| 452 | |
| 453 | switch (detail::to_ascii(*it)) { |
| 454 | case 'n': |
| 455 | set_brackets({}, {}); |
| 456 | ++it; |
| 457 | break; |
| 458 | case '?': |
| 459 | is_debug = true; |
| 460 | set_brackets({}, {}); |
| 461 | ++it; |
| 462 | if (it == end || *it != 's') report_error("invalid format specifier"); |
| 463 | FMT_FALLTHROUGH; |
| 464 | case 's': |
| 465 | if (!std::is_same<T, Char>::value) |
| 466 | report_error("invalid format specifier"); |
| 467 | if (!is_debug) { |
| 468 | set_brackets(detail::string_literal<Char, '"'>{}, |
| 469 | detail::string_literal<Char, '"'>{}); |
| 470 | set_separator({}); |
| 471 | detail::maybe_set_debug_format(underlying_, false); |
| 472 | } |
| 473 | ++it; |
| 474 | return it; |
| 475 | } |
| 476 | |
| 477 | if (it != end && *it != '}') { |
| 478 | if (*it != ':') report_error("invalid format specifier"); |
| 479 | detail::maybe_set_debug_format(underlying_, false); |
| 480 | ++it; |
| 481 | } |
| 482 | |
| 483 | ctx.advance_to(it); |
| 484 | return underlying_.parse(ctx); |
| 485 | } |
| 486 | |
| 487 | template <typename R, typename FormatContext> |
| 488 | auto format(R&& range, FormatContext& ctx) const -> decltype(ctx.out()) { |
| 489 | auto mapper = detail::range_mapper<buffered_context<Char>>(); |
| 490 | auto out = ctx.out(); |
| 491 | auto it = detail::range_begin(range); |
| 492 | auto end = detail::range_end(range); |
| 493 | if (is_debug) return write_debug_string(out, std::move(it), end); |
| 494 | |
| 495 | out = detail::copy<Char>(opening_bracket_, out); |
| 496 | int i = 0; |
| 497 | for (; it != end; ++it) { |
| 498 | if (i > 0) out = detail::copy<Char>(separator_, out); |
| 499 | ctx.advance_to(out); |
| 500 | auto&& item = *it; // Need an lvalue |
| 501 | out = underlying_.format(mapper.map(item), ctx); |
| 502 | ++i; |
| 503 | } |
| 504 | out = detail::copy<Char>(closing_bracket_, out); |
| 505 | return out; |
| 506 | } |
| 507 | }; |
| 508 | |
| 509 | FMT_EXPORT |
| 510 | template <typename T, typename Char, typename Enable = void> |
| 511 | struct range_format_kind |
| 512 | : conditional_t< |
| 513 | is_range<T, Char>::value, detail::range_format_kind_<T>, |
| 514 | std::integral_constant<range_format, range_format::disabled>> {}; |
| 515 | |
| 516 | template <typename R, typename Char> |
| 517 | struct formatter< |
| 518 | R, Char, |
| 519 | enable_if_t<conjunction< |
| 520 | bool_constant< |
| 521 | range_format_kind<R, Char>::value != range_format::disabled && |
| 522 | range_format_kind<R, Char>::value != range_format::map && |
| 523 | range_format_kind<R, Char>::value != range_format::string && |
| 524 | range_format_kind<R, Char>::value != range_format::debug_string> |
| 525 | // Workaround a bug in MSVC 2015 and earlier. |
| 526 | #if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910 |
| 527 | , |
| 528 | detail::is_formattable_delayed<R, Char> |
| 529 | #endif |
| 530 | >::value>> { |
| 531 | private: |
| 532 | using range_type = detail::maybe_const_range<R>; |
| 533 | range_formatter<detail::uncvref_type<range_type>, Char> range_formatter_; |
| 534 | |
| 535 | public: |
| 536 | using nonlocking = void; |
| 537 | |
| 538 | FMT_CONSTEXPR formatter() { |
| 539 | if (detail::const_check(range_format_kind<R, Char>::value != |
| 540 | range_format::set)) |
| 541 | return; |
| 542 | range_formatter_.set_brackets(detail::string_literal<Char, '{'>{}, |
| 543 | detail::string_literal<Char, '}'>{}); |
| 544 | } |
| 545 | |
| 546 | template <typename ParseContext> |
| 547 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 548 | return range_formatter_.parse(ctx); |
| 549 | } |
| 550 | |
| 551 | template <typename FormatContext> |
| 552 | auto format(range_type& range, FormatContext& ctx) const |
| 553 | -> decltype(ctx.out()) { |
| 554 | return range_formatter_.format(range, ctx); |
| 555 | } |
| 556 | }; |
| 557 | |
| 558 | // A map formatter. |
| 559 | template <typename R, typename Char> |
| 560 | struct formatter< |
| 561 | R, Char, |
| 562 | enable_if_t<range_format_kind<R, Char>::value == range_format::map>> { |
| 563 | private: |
| 564 | using map_type = detail::maybe_const_range<R>; |
| 565 | using element_type = detail::uncvref_type<map_type>; |
| 566 | |
| 567 | decltype(detail::tuple::get_formatters<element_type, Char>( |
| 568 | detail::tuple_index_sequence<element_type>())) formatters_; |
| 569 | bool no_delimiters_ = false; |
| 570 | |
| 571 | public: |
| 572 | FMT_CONSTEXPR formatter() {} |
| 573 | |
| 574 | template <typename ParseContext> |
| 575 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 576 | auto it = ctx.begin(); |
| 577 | auto end = ctx.end(); |
| 578 | if (it != end) { |
| 579 | if (detail::to_ascii(*it) == 'n') { |
| 580 | no_delimiters_ = true; |
| 581 | ++it; |
| 582 | } |
| 583 | if (it != end && *it != '}') { |
| 584 | if (*it != ':') report_error("invalid format specifier"); |
| 585 | ++it; |
| 586 | } |
| 587 | ctx.advance_to(it); |
| 588 | } |
| 589 | detail::for_each(formatters_, detail::parse_empty_specs<ParseContext>{ctx}); |
| 590 | return it; |
| 591 | } |
| 592 | |
| 593 | template <typename FormatContext> |
| 594 | auto format(map_type& map, FormatContext& ctx) const -> decltype(ctx.out()) { |
| 595 | auto out = ctx.out(); |
| 596 | basic_string_view<Char> open = detail::string_literal<Char, '{'>{}; |
| 597 | if (!no_delimiters_) out = detail::copy<Char>(open, out); |
| 598 | int i = 0; |
| 599 | auto mapper = detail::range_mapper<buffered_context<Char>>(); |
| 600 | basic_string_view<Char> sep = detail::string_literal<Char, ',', ' '>{}; |
| 601 | for (auto&& value : map) { |
| 602 | if (i > 0) out = detail::copy<Char>(sep, out); |
| 603 | ctx.advance_to(out); |
| 604 | detail::for_each2(formatters_, mapper.map(value), |
| 605 | detail::format_tuple_element<FormatContext>{ |
| 606 | 0, ctx, detail::string_literal<Char, ':', ' '>{}}); |
| 607 | ++i; |
| 608 | } |
| 609 | basic_string_view<Char> close = detail::string_literal<Char, '}'>{}; |
| 610 | if (!no_delimiters_) out = detail::copy<Char>(close, out); |
| 611 | return out; |
| 612 | } |
| 613 | }; |
| 614 | |
| 615 | // A (debug_)string formatter. |
| 616 | template <typename R, typename Char> |
| 617 | struct formatter< |
| 618 | R, Char, |
| 619 | enable_if_t<range_format_kind<R, Char>::value == range_format::string || |
| 620 | range_format_kind<R, Char>::value == |
| 621 | range_format::debug_string>> { |
| 622 | private: |
| 623 | using range_type = detail::maybe_const_range<R>; |
| 624 | using string_type = |
| 625 | conditional_t<std::is_constructible< |
| 626 | detail::std_string_view<Char>, |
| 627 | decltype(detail::range_begin(std::declval<R>())), |
| 628 | decltype(detail::range_end(std::declval<R>()))>::value, |
| 629 | detail::std_string_view<Char>, std::basic_string<Char>>; |
| 630 | |
| 631 | formatter<string_type, Char> underlying_; |
| 632 | |
| 633 | public: |
| 634 | template <typename ParseContext> |
| 635 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 636 | return underlying_.parse(ctx); |
| 637 | } |
| 638 | |
| 639 | template <typename FormatContext> |
| 640 | auto format(range_type& range, FormatContext& ctx) const |
| 641 | -> decltype(ctx.out()) { |
| 642 | auto out = ctx.out(); |
| 643 | if (detail::const_check(range_format_kind<R, Char>::value == |
| 644 | range_format::debug_string)) |
| 645 | *out++ = '"'; |
| 646 | out = underlying_.format( |
| 647 | string_type{detail::range_begin(range), detail::range_end(range)}, ctx); |
| 648 | if (detail::const_check(range_format_kind<R, Char>::value == |
| 649 | range_format::debug_string)) |
| 650 | *out++ = '"'; |
| 651 | return out; |
| 652 | } |
| 653 | }; |
| 654 | |
| 655 | template <typename It, typename Sentinel, typename Char = char> |
| 656 | struct join_view : detail::view { |
| 657 | It begin; |
| 658 | Sentinel end; |
| 659 | basic_string_view<Char> sep; |
| 660 | |
| 661 | join_view(It b, Sentinel e, basic_string_view<Char> s) |
| 662 | : begin(std::move(b)), end(e), sep(s) {} |
| 663 | }; |
| 664 | |
| 665 | template <typename It, typename Sentinel, typename Char> |
| 666 | struct formatter<join_view<It, Sentinel, Char>, Char> { |
| 667 | private: |
| 668 | using value_type = |
| 669 | #ifdef __cpp_lib_ranges |
| 670 | std::iter_value_t<It>; |
| 671 | #else |
| 672 | typename std::iterator_traits<It>::value_type; |
| 673 | #endif |
| 674 | formatter<remove_cvref_t<value_type>, Char> value_formatter_; |
| 675 | |
| 676 | using view_ref = conditional_t<std::is_copy_constructible<It>::value, |
| 677 | const join_view<It, Sentinel, Char>&, |
| 678 | join_view<It, Sentinel, Char>&&>; |
| 679 | |
| 680 | public: |
| 681 | using nonlocking = void; |
| 682 | |
| 683 | template <typename ParseContext> |
| 684 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> const Char* { |
| 685 | return value_formatter_.parse(ctx); |
| 686 | } |
| 687 | |
| 688 | template <typename FormatContext> |
| 689 | auto format(view_ref& value, FormatContext& ctx) const |
| 690 | -> decltype(ctx.out()) { |
| 691 | auto it = std::forward<view_ref>(value).begin; |
| 692 | auto out = ctx.out(); |
| 693 | if (it == value.end) return out; |
| 694 | out = value_formatter_.format(*it, ctx); |
| 695 | ++it; |
| 696 | while (it != value.end) { |
| 697 | out = detail::copy<Char>(value.sep.begin(), value.sep.end(), out); |
| 698 | ctx.advance_to(out); |
| 699 | out = value_formatter_.format(*it, ctx); |
| 700 | ++it; |
| 701 | } |
| 702 | return out; |
| 703 | } |
| 704 | }; |
| 705 | |
| 706 | /// Returns a view that formats the iterator range `[begin, end)` with elements |
| 707 | /// separated by `sep`. |
| 708 | template <typename It, typename Sentinel> |
| 709 | auto join(It begin, Sentinel end, string_view sep) -> join_view<It, Sentinel> { |
| 710 | return {std::move(begin), end, sep}; |
| 711 | } |
| 712 | |
| 713 | /** |
| 714 | * Returns a view that formats `range` with elements separated by `sep`. |
| 715 | * |
| 716 | * **Example**: |
| 717 | * |
| 718 | * auto v = std::vector<int>{1, 2, 3}; |
| 719 | * fmt::print("{}", fmt::join(v, ", ")); |
| 720 | * // Output: 1, 2, 3 |
| 721 | * |
| 722 | * `fmt::join` applies passed format specifiers to the range elements: |
| 723 | * |
| 724 | * fmt::print("{:02}", fmt::join(v, ", ")); |
| 725 | * // Output: 01, 02, 03 |
| 726 | */ |
| 727 | template <typename Range> |
| 728 | auto join(Range&& r, string_view sep) |
| 729 | -> join_view<decltype(detail::range_begin(r)), |
| 730 | decltype(detail::range_end(r))> { |
| 731 | return {detail::range_begin(r), detail::range_end(r), sep}; |
| 732 | } |
| 733 | |
| 734 | template <typename Char, typename... T> struct tuple_join_view : detail::view { |
| 735 | const std::tuple<T...>& tuple; |
| 736 | basic_string_view<Char> sep; |
| 737 | |
| 738 | tuple_join_view(const std::tuple<T...>& t, basic_string_view<Char> s) |
| 739 | : tuple(t), sep{s} {} |
| 740 | }; |
| 741 | |
| 742 | // Define FMT_TUPLE_JOIN_SPECIFIERS to enable experimental format specifiers |
| 743 | // support in tuple_join. It is disabled by default because of issues with |
| 744 | // the dynamic width and precision. |
| 745 | #ifndef FMT_TUPLE_JOIN_SPECIFIERS |
| 746 | # define FMT_TUPLE_JOIN_SPECIFIERS 0 |
| 747 | #endif |
| 748 | |
| 749 | template <typename Char, typename... T> |
| 750 | struct formatter<tuple_join_view<Char, T...>, Char> { |
| 751 | template <typename ParseContext> |
| 752 | FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { |
| 753 | return do_parse(ctx, std::integral_constant<size_t, sizeof...(T)>()); |
| 754 | } |
| 755 | |
| 756 | template <typename FormatContext> |
| 757 | auto format(const tuple_join_view<Char, T...>& value, |
| 758 | FormatContext& ctx) const -> typename FormatContext::iterator { |
| 759 | return do_format(value, ctx, |
| 760 | std::integral_constant<size_t, sizeof...(T)>()); |
| 761 | } |
| 762 | |
| 763 | private: |
| 764 | std::tuple<formatter<typename std::decay<T>::type, Char>...> formatters_; |
| 765 | |
| 766 | template <typename ParseContext> |
| 767 | FMT_CONSTEXPR auto do_parse(ParseContext& ctx, |
| 768 | std::integral_constant<size_t, 0>) |
| 769 | -> decltype(ctx.begin()) { |
| 770 | return ctx.begin(); |
| 771 | } |
| 772 | |
| 773 | template <typename ParseContext, size_t N> |
| 774 | FMT_CONSTEXPR auto do_parse(ParseContext& ctx, |
| 775 | std::integral_constant<size_t, N>) |
| 776 | -> decltype(ctx.begin()) { |
| 777 | auto end = ctx.begin(); |
| 778 | #if FMT_TUPLE_JOIN_SPECIFIERS |
| 779 | end = std::get<sizeof...(T) - N>(formatters_).parse(ctx); |
| 780 | if (N > 1) { |
| 781 | auto end1 = do_parse(ctx, std::integral_constant<size_t, N - 1>()); |
| 782 | if (end != end1) |
| 783 | report_error("incompatible format specs for tuple elements"); |
| 784 | } |
| 785 | #endif |
| 786 | return end; |
| 787 | } |
| 788 | |
| 789 | template <typename FormatContext> |
| 790 | auto do_format(const tuple_join_view<Char, T...>&, FormatContext& ctx, |
| 791 | std::integral_constant<size_t, 0>) const -> |
| 792 | typename FormatContext::iterator { |
| 793 | return ctx.out(); |
| 794 | } |
| 795 | |
| 796 | template <typename FormatContext, size_t N> |
| 797 | auto do_format(const tuple_join_view<Char, T...>& value, FormatContext& ctx, |
| 798 | std::integral_constant<size_t, N>) const -> |
| 799 | typename FormatContext::iterator { |
| 800 | auto out = std::get<sizeof...(T) - N>(formatters_) |
| 801 | .format(std::get<sizeof...(T) - N>(value.tuple), ctx); |
| 802 | if (N <= 1) return out; |
| 803 | out = detail::copy<Char>(value.sep, out); |
| 804 | ctx.advance_to(out); |
| 805 | return do_format(value, ctx, std::integral_constant<size_t, N - 1>()); |
| 806 | } |
| 807 | }; |
| 808 | |
| 809 | namespace detail { |
| 810 | // Check if T has an interface like a container adaptor (e.g. std::stack, |
| 811 | // std::queue, std::priority_queue). |
| 812 | template <typename T> class is_container_adaptor_like { |
| 813 | template <typename U> static auto check(U* p) -> typename U::container_type; |
| 814 | template <typename> static void check(...); |
| 815 | |
| 816 | public: |
| 817 | static constexpr const bool value = |
| 818 | !std::is_void<decltype(check<T>(nullptr))>::value; |
| 819 | }; |
| 820 | |
| 821 | template <typename Container> struct all { |
| 822 | const Container& c; |
| 823 | auto begin() const -> typename Container::const_iterator { return c.begin(); } |
| 824 | auto end() const -> typename Container::const_iterator { return c.end(); } |
| 825 | }; |
| 826 | } // namespace detail |
| 827 | |
| 828 | template <typename T, typename Char> |
| 829 | struct formatter< |
| 830 | T, Char, |
| 831 | enable_if_t<conjunction<detail::is_container_adaptor_like<T>, |
| 832 | bool_constant<range_format_kind<T, Char>::value == |
| 833 | range_format::disabled>>::value>> |
| 834 | : formatter<detail::all<typename T::container_type>, Char> { |
| 835 | using all = detail::all<typename T::container_type>; |
| 836 | template <typename FormatContext> |
| 837 | auto format(const T& t, FormatContext& ctx) const -> decltype(ctx.out()) { |
| 838 | struct getter : T { |
| 839 | static auto get(const T& t) -> all { |
| 840 | return {t.*(&getter::c)}; // Access c through the derived class. |
| 841 | } |
| 842 | }; |
| 843 | return formatter<all>::format(getter::get(t), ctx); |
| 844 | } |
| 845 | }; |
| 846 | |
| 847 | FMT_BEGIN_EXPORT |
| 848 | |
| 849 | /** |
| 850 | * Returns an object that formats `std::tuple` with elements separated by `sep`. |
| 851 | * |
| 852 | * **Example**: |
| 853 | * |
| 854 | * auto t = std::tuple<int, char>{1, 'a'}; |
| 855 | * fmt::print("{}", fmt::join(t, ", ")); |
| 856 | * // Output: 1, a |
| 857 | */ |
| 858 | template <typename... T> |
| 859 | FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple, string_view sep) |
| 860 | -> tuple_join_view<char, T...> { |
| 861 | return {tuple, sep}; |
| 862 | } |
| 863 | |
| 864 | /** |
| 865 | * Returns an object that formats `std::initializer_list` with elements |
| 866 | * separated by `sep`. |
| 867 | * |
| 868 | * **Example**: |
| 869 | * |
| 870 | * fmt::print("{}", fmt::join({1, 2, 3}, ", ")); |
| 871 | * // Output: "1, 2, 3" |
| 872 | */ |
| 873 | template <typename T> |
| 874 | auto join(std::initializer_list<T> list, string_view sep) |
| 875 | -> join_view<const T*, const T*> { |
| 876 | return join(std::begin(list), std::end(list), sep); |
| 877 | } |
| 878 | |
| 879 | FMT_END_EXPORT |
| 880 | FMT_END_NAMESPACE |
| 881 | |
| 882 | #endif // FMT_RANGES_H_ |