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- // Formatting library for C++ - experimental range support
- //
- // Copyright (c) 2012 - present, Victor Zverovich
- // All rights reserved.
- //
- // For the license information refer to format.h.
- //
- // Copyright (c) 2018 - present, Remotion (Igor Schulz)
- // All Rights Reserved
- // {fmt} support for ranges, containers and types tuple interface.
-
- #ifndef FMT_RANGES_H_
- #define FMT_RANGES_H_
-
- #include <type_traits>
- #include "format.h"
-
- // output only up to N items from the range.
- #ifndef FMT_RANGE_OUTPUT_LENGTH_LIMIT
- # define FMT_RANGE_OUTPUT_LENGTH_LIMIT 256
- #endif
-
- FMT_BEGIN_NAMESPACE
-
- template <typename Char> struct formatting_base {
- template <typename ParseContext>
- FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
- return ctx.begin();
- }
- };
-
- template <typename Char, typename Enable = void>
- struct formatting_range : formatting_base<Char> {
- static FMT_CONSTEXPR_DECL const std::size_t range_length_limit =
- FMT_RANGE_OUTPUT_LENGTH_LIMIT; // output only up to N items from the
- // range.
- Char prefix;
- Char delimiter;
- Char postfix;
- formatting_range() : prefix('{'), delimiter(','), postfix('}') {}
- static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
- static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
- };
-
- template <typename Char, typename Enable = void>
- struct formatting_tuple : formatting_base<Char> {
- Char prefix;
- Char delimiter;
- Char postfix;
- formatting_tuple() : prefix('('), delimiter(','), postfix(')') {}
- static FMT_CONSTEXPR_DECL const bool add_delimiter_spaces = true;
- static FMT_CONSTEXPR_DECL const bool add_prepostfix_space = false;
- };
-
- namespace internal {
-
- template <typename RangeT, typename OutputIterator>
- OutputIterator copy(const RangeT& range, OutputIterator out) {
- for (auto it = range.begin(), end = range.end(); it != end; ++it)
- *out++ = *it;
- return out;
- }
-
- template <typename OutputIterator>
- OutputIterator copy(const char* str, OutputIterator out) {
- while (*str) *out++ = *str++;
- return out;
- }
-
- template <typename OutputIterator>
- OutputIterator copy(char ch, OutputIterator out) {
- *out++ = ch;
- return out;
- }
-
- /// Return true value if T has std::string interface, like std::string_view.
- template <typename T> class is_like_std_string {
- 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 FMT_CONSTEXPR_DECL const bool value =
- is_string<T>::value || !std::is_void<decltype(check<T>(nullptr))>::value;
- };
-
- template <typename Char>
- struct is_like_std_string<fmt::basic_string_view<Char>> : std::true_type {};
-
- template <typename... Ts> struct conditional_helper {};
-
- template <typename T, typename _ = void> struct is_range_ : std::false_type {};
-
- #if !FMT_MSC_VER || FMT_MSC_VER > 1800
- template <typename T>
- struct is_range_<
- T, conditional_t<false,
- conditional_helper<decltype(std::declval<T>().begin()),
- decltype(std::declval<T>().end())>,
- void>> : std::true_type {};
- #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,
- (void)std::declval<typename std::tuple_element<0, U>::type>(),
- int());
- template <typename> static void check(...);
-
- public:
- static FMT_CONSTEXPR_DECL const bool value =
- !std::is_void<decltype(check<T>(nullptr))>::value;
- };
-
- // Check for integer_sequence
- #if defined(__cpp_lib_integer_sequence) || FMT_MSC_VER >= 1900
- template <typename T, T... N>
- using integer_sequence = std::integer_sequence<T, N...>;
- template <std::size_t... N> using index_sequence = std::index_sequence<N...>;
- template <std::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 std::size_t size() { return sizeof...(N); }
- };
-
- template <std::size_t... N>
- using index_sequence = integer_sequence<std::size_t, N...>;
-
- template <typename T, std::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 <std::size_t N>
- using make_index_sequence = make_integer_sequence<std::size_t, N>;
- #endif
-
- template <class Tuple, class F, size_t... Is>
- void for_each(index_sequence<Is...>, Tuple&& tup, F&& f) FMT_NOEXCEPT {
- using std::get;
- // using free function get<I>(T) now.
- const int _[] = {0, ((void)f(get<Is>(tup)), 0)...};
- (void)_; // blocks warnings
- }
-
- template <class T>
- FMT_CONSTEXPR make_index_sequence<std::tuple_size<T>::value> get_indexes(
- T const&) {
- return {};
- }
-
- template <class Tuple, class F> void for_each(Tuple&& tup, F&& f) {
- const auto indexes = get_indexes(tup);
- for_each(indexes, std::forward<Tuple>(tup), std::forward<F>(f));
- }
-
- template <typename Arg, FMT_ENABLE_IF(!is_like_std_string<
- typename std::decay<Arg>::type>::value)>
- FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
- return add_space ? " {}" : "{}";
- }
-
- template <typename Arg, FMT_ENABLE_IF(is_like_std_string<
- typename std::decay<Arg>::type>::value)>
- FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const Arg&) {
- return add_space ? " \"{}\"" : "\"{}\"";
- }
-
- FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char*) {
- return add_space ? " \"{}\"" : "\"{}\"";
- }
- FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t*) {
- return add_space ? L" \"{}\"" : L"\"{}\"";
- }
-
- FMT_CONSTEXPR const char* format_str_quoted(bool add_space, const char) {
- return add_space ? " '{}'" : "'{}'";
- }
- FMT_CONSTEXPR const wchar_t* format_str_quoted(bool add_space, const wchar_t) {
- return add_space ? L" '{}'" : L"'{}'";
- }
-
- } // namespace internal
-
- template <typename T> struct is_tuple_like {
- static FMT_CONSTEXPR_DECL const bool value =
- internal::is_tuple_like_<T>::value && !internal::is_range_<T>::value;
- };
-
- template <typename TupleT, typename Char>
- struct formatter<TupleT, Char, enable_if_t<fmt::is_tuple_like<TupleT>::value>> {
- private:
- // C++11 generic lambda for format()
- template <typename FormatContext> struct format_each {
- template <typename T> void operator()(const T& v) {
- if (i > 0) {
- if (formatting.add_prepostfix_space) {
- *out++ = ' ';
- }
- out = internal::copy(formatting.delimiter, out);
- }
- out = format_to(out,
- internal::format_str_quoted(
- (formatting.add_delimiter_spaces && i > 0), v),
- v);
- ++i;
- }
-
- formatting_tuple<Char>& formatting;
- std::size_t& i;
- typename std::add_lvalue_reference<decltype(
- std::declval<FormatContext>().out())>::type out;
- };
-
- public:
- formatting_tuple<Char> formatting;
-
- template <typename ParseContext>
- FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
- return formatting.parse(ctx);
- }
-
- template <typename FormatContext = format_context>
- auto format(const TupleT& values, FormatContext& ctx) -> decltype(ctx.out()) {
- auto out = ctx.out();
- std::size_t i = 0;
- internal::copy(formatting.prefix, out);
-
- internal::for_each(values, format_each<FormatContext>{formatting, i, out});
- if (formatting.add_prepostfix_space) {
- *out++ = ' ';
- }
- internal::copy(formatting.postfix, out);
-
- return ctx.out();
- }
- };
-
- template <typename T, typename Char> struct is_range {
- static FMT_CONSTEXPR_DECL const bool value =
- internal::is_range_<T>::value &&
- !internal::is_like_std_string<T>::value &&
- !std::is_convertible<T, std::basic_string<Char>>::value;
- };
-
- template <typename RangeT, typename Char>
- struct formatter<RangeT, Char,
- enable_if_t<fmt::is_range<RangeT, Char>::value>> {
- formatting_range<Char> formatting;
-
- template <typename ParseContext>
- FMT_CONSTEXPR auto parse(ParseContext& ctx) -> decltype(ctx.begin()) {
- return formatting.parse(ctx);
- }
-
- template <typename FormatContext>
- typename FormatContext::iterator format(const RangeT& values,
- FormatContext& ctx) {
- auto out = internal::copy(formatting.prefix, ctx.out());
- std::size_t i = 0;
- for (auto it = values.begin(), end = values.end(); it != end; ++it) {
- if (i > 0) {
- if (formatting.add_prepostfix_space) *out++ = ' ';
- out = internal::copy(formatting.delimiter, out);
- }
- out = format_to(out,
- internal::format_str_quoted(
- (formatting.add_delimiter_spaces && i > 0), *it),
- *it);
- if (++i > formatting.range_length_limit) {
- out = format_to(out, " ... <other elements>");
- break;
- }
- }
- if (formatting.add_prepostfix_space) *out++ = ' ';
- return internal::copy(formatting.postfix, out);
- }
- };
-
- FMT_END_NAMESPACE
-
- #endif // FMT_RANGES_H_
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