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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_
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