Mercurial > minori
view dep/fmt/include/fmt/ranges.h @ 343:1faa72660932
*: transfer back to cmake from autotools
autotools just made lots of things more complicated than
they should have and many things broke (i.e. translations)
author | Paper <paper@paper.us.eu.org> |
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date | Thu, 20 Jun 2024 05:56:06 -0400 |
parents | 4aeffed717ef |
children |
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// Formatting library for C++ - range and tuple support // // Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors // All rights reserved. // // For the license information refer to format.h. #ifndef FMT_RANGES_H_ #define FMT_RANGES_H_ #include <initializer_list> #include <tuple> #include <type_traits> #include "format.h" FMT_BEGIN_NAMESPACE namespace detail { template <typename Range, typename OutputIt> auto copy(const Range& range, OutputIt out) -> OutputIt { for (auto it = range.begin(), end = range.end(); it != end; ++it) *out++ = *it; return out; } template <typename OutputIt> auto copy(const char* str, OutputIt out) -> OutputIt { while (*str) *out++ = *str++; return out; } template <typename OutputIt> auto copy(char ch, OutputIt out) -> OutputIt { *out++ = ch; return out; } template <typename OutputIt> auto copy(wchar_t ch, OutputIt out) -> OutputIt { *out++ = ch; return out; } // Returns true if T has a std::string-like interface, like std::string_view. template <typename T> class is_std_string_like { template <typename U> static auto check(U* p) -> decltype((void)p->find('a'), p->length(), (void)p->data(), int()); template <typename> static void check(...); public: static constexpr const bool value = is_string<T>::value || std::is_convertible<T, std_string_view<char>>::value || !std::is_void<decltype(check<T>(nullptr))>::value; }; template <typename Char> struct is_std_string_like<fmt::basic_string_view<Char>> : std::true_type {}; template <typename T> class is_map { template <typename U> static auto check(U*) -> typename U::mapped_type; template <typename> static void check(...); public: #ifdef FMT_FORMAT_MAP_AS_LIST // DEPRECATED! static constexpr const bool value = false; #else static constexpr const bool value = !std::is_void<decltype(check<T>(nullptr))>::value; #endif }; template <typename T> class is_set { template <typename U> static auto check(U*) -> typename U::key_type; template <typename> static void check(...); public: #ifdef FMT_FORMAT_SET_AS_LIST // DEPRECATED! static constexpr const bool value = false; #else static constexpr const bool value = !std::is_void<decltype(check<T>(nullptr))>::value && !is_map<T>::value; #endif }; template <typename... Ts> struct conditional_helper {}; template <typename T, typename _ = void> struct is_range_ : std::false_type {}; #if !FMT_MSC_VERSION || FMT_MSC_VERSION > 1800 # define FMT_DECLTYPE_RETURN(val) \ ->decltype(val) { return val; } \ static_assert( \ true, "") // This makes it so that a semicolon is required after the // macro, which helps clang-format handle the formatting. // C array overload template <typename T, std::size_t N> auto range_begin(const T (&arr)[N]) -> const T* { return arr; } template <typename T, std::size_t N> auto range_end(const T (&arr)[N]) -> const T* { return arr + N; } template <typename T, typename Enable = void> struct has_member_fn_begin_end_t : std::false_type {}; template <typename T> struct has_member_fn_begin_end_t<T, void_t<decltype(std::declval<T>().begin()), decltype(std::declval<T>().end())>> : std::true_type {}; // Member function overload template <typename T> auto range_begin(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).begin()); template <typename T> auto range_end(T&& rng) FMT_DECLTYPE_RETURN(static_cast<T&&>(rng).end()); // ADL overload. Only participates in overload resolution if member functions // are not found. template <typename T> auto range_begin(T&& rng) -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value, decltype(begin(static_cast<T&&>(rng)))> { return begin(static_cast<T&&>(rng)); } template <typename T> auto range_end(T&& rng) -> enable_if_t<!has_member_fn_begin_end_t<T&&>::value, decltype(end(static_cast<T&&>(rng)))> { return end(static_cast<T&&>(rng)); } template <typename T, typename Enable = void> struct has_const_begin_end : std::false_type {}; template <typename T, typename Enable = void> struct has_mutable_begin_end : std::false_type {}; template <typename T> struct has_const_begin_end< T, void_t< decltype(detail::range_begin(std::declval<const remove_cvref_t<T>&>())), decltype(detail::range_end(std::declval<const remove_cvref_t<T>&>()))>> : std::true_type {}; template <typename T> struct has_mutable_begin_end< T, void_t<decltype(detail::range_begin(std::declval<T>())), decltype(detail::range_end(std::declval<T>())), // the extra int here is because older versions of MSVC don't // SFINAE properly unless there are distinct types int>> : std::true_type {}; template <typename T> struct is_range_<T, void> : std::integral_constant<bool, (has_const_begin_end<T>::value || has_mutable_begin_end<T>::value)> {}; # undef FMT_DECLTYPE_RETURN #endif // tuple_size and tuple_element check. template <typename T> class is_tuple_like_ { template <typename U> static auto check(U* p) -> decltype(std::tuple_size<U>::value, int()); template <typename> static void check(...); public: static constexpr const bool value = !std::is_void<decltype(check<T>(nullptr))>::value; }; // Check for integer_sequence #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VERSION >= 1900 template <typename T, T... N> using integer_sequence = std::integer_sequence<T, N...>; template <size_t... N> using index_sequence = std::index_sequence<N...>; template <size_t N> using make_index_sequence = std::make_index_sequence<N>; #else template <typename T, T... N> struct integer_sequence { using value_type = T; static FMT_CONSTEXPR auto size() -> size_t { return sizeof...(N); } }; template <size_t... N> using index_sequence = integer_sequence<size_t, N...>; template <typename T, size_t N, T... Ns> struct make_integer_sequence : make_integer_sequence<T, N - 1, N - 1, Ns...> {}; template <typename T, T... Ns> struct make_integer_sequence<T, 0, Ns...> : integer_sequence<T, Ns...> {}; template <size_t N> using make_index_sequence = make_integer_sequence<size_t, N>; #endif template <typename T> using tuple_index_sequence = make_index_sequence<std::tuple_size<T>::value>; template <typename T, typename C, bool = is_tuple_like_<T>::value> class is_tuple_formattable_ { public: static constexpr const bool value = false; }; template <typename T, typename C> class is_tuple_formattable_<T, C, true> { template <std::size_t... Is> static auto check2(index_sequence<Is...>, integer_sequence<bool, (Is == Is)...>) -> std::true_type; static auto check2(...) -> std::false_type; template <std::size_t... Is> static auto check(index_sequence<Is...>) -> decltype(check2( index_sequence<Is...>{}, integer_sequence<bool, (is_formattable<typename std::tuple_element<Is, T>::type, C>::value)...>{})); public: static constexpr const bool value = decltype(check(tuple_index_sequence<T>{}))::value; }; template <typename Tuple, typename F, size_t... Is> FMT_CONSTEXPR void for_each(index_sequence<Is...>, Tuple&& t, F&& f) { using std::get; // Using a free function get<Is>(Tuple) now. const int unused[] = {0, ((void)f(get<Is>(t)), 0)...}; ignore_unused(unused); } template <typename Tuple, typename F> FMT_CONSTEXPR void for_each(Tuple&& t, F&& f) { for_each(tuple_index_sequence<remove_cvref_t<Tuple>>(), std::forward<Tuple>(t), std::forward<F>(f)); } template <typename Tuple1, typename Tuple2, typename F, size_t... Is> void for_each2(index_sequence<Is...>, Tuple1&& t1, Tuple2&& t2, F&& f) { using std::get; const int unused[] = {0, ((void)f(get<Is>(t1), get<Is>(t2)), 0)...}; ignore_unused(unused); } template <typename Tuple1, typename Tuple2, typename F> void for_each2(Tuple1&& t1, Tuple2&& t2, F&& f) { for_each2(tuple_index_sequence<remove_cvref_t<Tuple1>>(), std::forward<Tuple1>(t1), std::forward<Tuple2>(t2), std::forward<F>(f)); } namespace tuple { // Workaround a bug in MSVC 2019 (v140). template <typename Char, typename... T> using result_t = std::tuple<formatter<remove_cvref_t<T>, Char>...>; using std::get; template <typename Tuple, typename Char, std::size_t... Is> auto get_formatters(index_sequence<Is...>) -> result_t<Char, decltype(get<Is>(std::declval<Tuple>()))...>; } // namespace tuple #if FMT_MSC_VERSION && FMT_MSC_VERSION < 1920 // Older MSVC doesn't get the reference type correctly for arrays. template <typename R> struct range_reference_type_impl { using type = decltype(*detail::range_begin(std::declval<R&>())); }; template <typename T, std::size_t N> struct range_reference_type_impl<T[N]> { using type = T&; }; template <typename T> using range_reference_type = typename range_reference_type_impl<T>::type; #else template <typename Range> using range_reference_type = decltype(*detail::range_begin(std::declval<Range&>())); #endif // We don't use the Range's value_type for anything, but we do need the Range's // reference type, with cv-ref stripped. template <typename Range> using uncvref_type = remove_cvref_t<range_reference_type<Range>>; template <typename Formatter> FMT_CONSTEXPR auto maybe_set_debug_format(Formatter& f, bool set) -> decltype(f.set_debug_format(set)) { f.set_debug_format(set); } template <typename Formatter> FMT_CONSTEXPR void maybe_set_debug_format(Formatter&, ...) {} // These are not generic lambdas for compatibility with C++11. template <typename ParseContext> struct parse_empty_specs { template <typename Formatter> FMT_CONSTEXPR void operator()(Formatter& f) { f.parse(ctx); detail::maybe_set_debug_format(f, true); } ParseContext& ctx; }; template <typename FormatContext> struct format_tuple_element { using char_type = typename FormatContext::char_type; template <typename T> void operator()(const formatter<T, char_type>& f, const T& v) { if (i > 0) ctx.advance_to(detail::copy_str<char_type>(separator, ctx.out())); ctx.advance_to(f.format(v, ctx)); ++i; } int i; FormatContext& ctx; basic_string_view<char_type> separator; }; } // namespace detail template <typename T> struct is_tuple_like { static constexpr const bool value = detail::is_tuple_like_<T>::value && !detail::is_range_<T>::value; }; template <typename T, typename C> struct is_tuple_formattable { static constexpr const bool value = detail::is_tuple_formattable_<T, C>::value; }; template <typename Tuple, typename Char> struct formatter<Tuple, Char, enable_if_t<fmt::is_tuple_like<Tuple>::value && fmt::is_tuple_formattable<Tuple, Char>::value>> { private: decltype(detail::tuple::get_formatters<Tuple, Char>( detail::tuple_index_sequence<Tuple>())) formatters_; basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{}; basic_string_view<Char> opening_bracket_ = detail::string_literal<Char, '('>{}; basic_string_view<Char> closing_bracket_ = detail::string_literal<Char, ')'>{}; public: FMT_CONSTEXPR formatter() {} FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) { separator_ = sep; } FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open, basic_string_view<Char> close) { opening_bracket_ = open; closing_bracket_ = close; } template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { auto it = ctx.begin(); if (it != ctx.end() && *it != '}') FMT_THROW(format_error("invalid format specifier")); detail::for_each(formatters_, detail::parse_empty_specs<ParseContext>{ctx}); return it; } template <typename FormatContext> auto format(const Tuple& value, FormatContext& ctx) const -> decltype(ctx.out()) { ctx.advance_to(detail::copy_str<Char>(opening_bracket_, ctx.out())); detail::for_each2( formatters_, value, detail::format_tuple_element<FormatContext>{0, ctx, separator_}); return detail::copy_str<Char>(closing_bracket_, ctx.out()); } }; template <typename T, typename Char> struct is_range { static constexpr const bool value = detail::is_range_<T>::value && !detail::is_std_string_like<T>::value && !std::is_convertible<T, std::basic_string<Char>>::value && !std::is_convertible<T, detail::std_string_view<Char>>::value; }; namespace detail { template <typename Context> struct range_mapper { using mapper = arg_mapper<Context>; template <typename T, FMT_ENABLE_IF(has_formatter<remove_cvref_t<T>, Context>::value)> static auto map(T&& value) -> T&& { return static_cast<T&&>(value); } template <typename T, FMT_ENABLE_IF(!has_formatter<remove_cvref_t<T>, Context>::value)> static auto map(T&& value) -> decltype(mapper().map(static_cast<T&&>(value))) { return mapper().map(static_cast<T&&>(value)); } }; template <typename Char, typename Element> using range_formatter_type = formatter<remove_cvref_t<decltype(range_mapper<buffer_context<Char>>{}.map( std::declval<Element>()))>, Char>; template <typename R> using maybe_const_range = conditional_t<has_const_begin_end<R>::value, const R, R>; // Workaround a bug in MSVC 2015 and earlier. #if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910 template <typename R, typename Char> struct is_formattable_delayed : is_formattable<uncvref_type<maybe_const_range<R>>, Char> {}; #endif } // namespace detail template <typename...> struct conjunction : std::true_type {}; template <typename P> struct conjunction<P> : P {}; template <typename P1, typename... Pn> struct conjunction<P1, Pn...> : conditional_t<bool(P1::value), conjunction<Pn...>, P1> {}; template <typename T, typename Char, typename Enable = void> struct range_formatter; template <typename T, typename Char> struct range_formatter< T, Char, enable_if_t<conjunction<std::is_same<T, remove_cvref_t<T>>, is_formattable<T, Char>>::value>> { private: detail::range_formatter_type<Char, T> underlying_; basic_string_view<Char> separator_ = detail::string_literal<Char, ',', ' '>{}; basic_string_view<Char> opening_bracket_ = detail::string_literal<Char, '['>{}; basic_string_view<Char> closing_bracket_ = detail::string_literal<Char, ']'>{}; public: FMT_CONSTEXPR range_formatter() {} FMT_CONSTEXPR auto underlying() -> detail::range_formatter_type<Char, T>& { return underlying_; } FMT_CONSTEXPR void set_separator(basic_string_view<Char> sep) { separator_ = sep; } FMT_CONSTEXPR void set_brackets(basic_string_view<Char> open, basic_string_view<Char> close) { opening_bracket_ = open; closing_bracket_ = close; } template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { auto it = ctx.begin(); auto end = ctx.end(); if (it != end && *it == 'n') { set_brackets({}, {}); ++it; } if (it != end && *it != '}') { if (*it != ':') FMT_THROW(format_error("invalid format specifier")); ++it; } else { detail::maybe_set_debug_format(underlying_, true); } ctx.advance_to(it); return underlying_.parse(ctx); } template <typename R, typename FormatContext> auto format(R&& range, FormatContext& ctx) const -> decltype(ctx.out()) { detail::range_mapper<buffer_context<Char>> mapper; auto out = ctx.out(); out = detail::copy_str<Char>(opening_bracket_, out); int i = 0; auto it = detail::range_begin(range); auto end = detail::range_end(range); for (; it != end; ++it) { if (i > 0) out = detail::copy_str<Char>(separator_, out); ctx.advance_to(out); auto&& item = *it; out = underlying_.format(mapper.map(item), ctx); ++i; } out = detail::copy_str<Char>(closing_bracket_, out); return out; } }; enum class range_format { disabled, map, set, sequence, string, debug_string }; namespace detail { template <typename T> struct range_format_kind_ : std::integral_constant<range_format, std::is_same<uncvref_type<T>, T>::value ? range_format::disabled : is_map<T>::value ? range_format::map : is_set<T>::value ? range_format::set : range_format::sequence> {}; template <range_format K, typename R, typename Char, typename Enable = void> struct range_default_formatter; template <range_format K> using range_format_constant = std::integral_constant<range_format, K>; template <range_format K, typename R, typename Char> struct range_default_formatter< K, R, Char, enable_if_t<(K == range_format::sequence || K == range_format::map || K == range_format::set)>> { using range_type = detail::maybe_const_range<R>; range_formatter<detail::uncvref_type<range_type>, Char> underlying_; FMT_CONSTEXPR range_default_formatter() { init(range_format_constant<K>()); } FMT_CONSTEXPR void init(range_format_constant<range_format::set>) { underlying_.set_brackets(detail::string_literal<Char, '{'>{}, detail::string_literal<Char, '}'>{}); } FMT_CONSTEXPR void init(range_format_constant<range_format::map>) { underlying_.set_brackets(detail::string_literal<Char, '{'>{}, detail::string_literal<Char, '}'>{}); underlying_.underlying().set_brackets({}, {}); underlying_.underlying().set_separator( detail::string_literal<Char, ':', ' '>{}); } FMT_CONSTEXPR void init(range_format_constant<range_format::sequence>) {} template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { return underlying_.parse(ctx); } template <typename FormatContext> auto format(range_type& range, FormatContext& ctx) const -> decltype(ctx.out()) { return underlying_.format(range, ctx); } }; } // namespace detail template <typename T, typename Char, typename Enable = void> struct range_format_kind : conditional_t< is_range<T, Char>::value, detail::range_format_kind_<T>, std::integral_constant<range_format, range_format::disabled>> {}; template <typename R, typename Char> struct formatter< R, Char, enable_if_t<conjunction<bool_constant<range_format_kind<R, Char>::value != range_format::disabled> // Workaround a bug in MSVC 2015 and earlier. #if !FMT_MSC_VERSION || FMT_MSC_VERSION >= 1910 , detail::is_formattable_delayed<R, Char> #endif >::value>> : detail::range_default_formatter<range_format_kind<R, Char>::value, R, Char> { }; template <typename Char, typename... T> struct tuple_join_view : detail::view { const std::tuple<T...>& tuple; basic_string_view<Char> sep; tuple_join_view(const std::tuple<T...>& t, basic_string_view<Char> s) : tuple(t), sep{s} {} }; // Define FMT_TUPLE_JOIN_SPECIFIERS to enable experimental format specifiers // support in tuple_join. It is disabled by default because of issues with // the dynamic width and precision. #ifndef FMT_TUPLE_JOIN_SPECIFIERS # define FMT_TUPLE_JOIN_SPECIFIERS 0 #endif template <typename Char, typename... T> struct formatter<tuple_join_view<Char, T...>, Char> { template <typename ParseContext> FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) { return do_parse(ctx, std::integral_constant<size_t, sizeof...(T)>()); } template <typename FormatContext> auto format(const tuple_join_view<Char, T...>& value, FormatContext& ctx) const -> typename FormatContext::iterator { return do_format(value, ctx, std::integral_constant<size_t, sizeof...(T)>()); } private: std::tuple<formatter<typename std::decay<T>::type, Char>...> formatters_; template <typename ParseContext> FMT_CONSTEXPR auto do_parse(ParseContext& ctx, std::integral_constant<size_t, 0>) -> decltype(ctx.begin()) { return ctx.begin(); } template <typename ParseContext, size_t N> FMT_CONSTEXPR auto do_parse(ParseContext& ctx, std::integral_constant<size_t, N>) -> decltype(ctx.begin()) { auto end = ctx.begin(); #if FMT_TUPLE_JOIN_SPECIFIERS end = std::get<sizeof...(T) - N>(formatters_).parse(ctx); if (N > 1) { auto end1 = do_parse(ctx, std::integral_constant<size_t, N - 1>()); if (end != end1) FMT_THROW(format_error("incompatible format specs for tuple elements")); } #endif return end; } template <typename FormatContext> auto do_format(const tuple_join_view<Char, T...>&, FormatContext& ctx, std::integral_constant<size_t, 0>) const -> typename FormatContext::iterator { return ctx.out(); } template <typename FormatContext, size_t N> auto do_format(const tuple_join_view<Char, T...>& value, FormatContext& ctx, std::integral_constant<size_t, N>) const -> typename FormatContext::iterator { auto out = std::get<sizeof...(T) - N>(formatters_) .format(std::get<sizeof...(T) - N>(value.tuple), ctx); if (N > 1) { out = std::copy(value.sep.begin(), value.sep.end(), out); ctx.advance_to(out); return do_format(value, ctx, std::integral_constant<size_t, N - 1>()); } return out; } }; namespace detail { // Check if T has an interface like a container adaptor (e.g. std::stack, // std::queue, std::priority_queue). template <typename T> class is_container_adaptor_like { template <typename U> static auto check(U* p) -> typename U::container_type; template <typename> static void check(...); public: static constexpr const bool value = !std::is_void<decltype(check<T>(nullptr))>::value; }; template <typename Container> struct all { const Container& c; auto begin() const -> typename Container::const_iterator { return c.begin(); } auto end() const -> typename Container::const_iterator { return c.end(); } }; } // namespace detail template <typename T, typename Char> struct formatter< T, Char, enable_if_t<conjunction<detail::is_container_adaptor_like<T>, bool_constant<range_format_kind<T, Char>::value == range_format::disabled>>::value>> : formatter<detail::all<typename T::container_type>, Char> { using all = detail::all<typename T::container_type>; template <typename FormatContext> auto format(const T& t, FormatContext& ctx) const -> decltype(ctx.out()) { struct getter : T { static auto get(const T& t) -> all { return {t.*(&getter::c)}; // Access c through the derived class. } }; return formatter<all>::format(getter::get(t), ctx); } }; FMT_BEGIN_EXPORT /** \rst Returns an object that formats `tuple` with elements separated by `sep`. **Example**:: std::tuple<int, char> t = {1, 'a'}; fmt::print("{}", fmt::join(t, ", ")); // Output: "1, a" \endrst */ template <typename... T> FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple, string_view sep) -> tuple_join_view<char, T...> { return {tuple, sep}; } template <typename... T> FMT_CONSTEXPR auto join(const std::tuple<T...>& tuple, basic_string_view<wchar_t> sep) -> tuple_join_view<wchar_t, T...> { return {tuple, sep}; } /** \rst Returns an object that formats `initializer_list` with elements separated by `sep`. **Example**:: fmt::print("{}", fmt::join({1, 2, 3}, ", ")); // Output: "1, 2, 3" \endrst */ template <typename T> auto join(std::initializer_list<T> list, string_view sep) -> join_view<const T*, const T*> { return join(std::begin(list), std::end(list), sep); } FMT_END_EXPORT FMT_END_NAMESPACE #endif // FMT_RANGES_H_