...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
template<typename T> concept code_unit = std::same_as<std::remove_cv_t<T>, char> || std::same_as<std::remove_cv_t<T>, wchar_t> || std::same_as<std::remove_cv_t<T>, char8_t> || std::same_as<std::remove_cv_t<T>, char16_t>|| std::same_as<std::remove_cv_t<T>, char32_t>; template<typename T> concept parsable_iter = std::forward_iterator<T> && code_unit<std::iter_value_t<T>>; template<typename T> concept parsable_range = std::ranges::forward_range<T> && code_unit<std::ranges::range_value_t<T>>; template<typename T> concept parsable_pointer = std::is_pointer_v<std::remove_cvref_t<T>> && code_unit<std::remove_pointer_t<std::remove_cvref_t<T>>>; template<typename T> concept parsable_range_like = parsable_range<T> || parsable_pointer<T>; template<typename T> concept range_like = std::ranges::range<T> || parsable_pointer<T>; template< typename I, typename S, typename ErrorHandler, typename GlobalState> using minimal_parse_context = decltype(detail::make_context<false, false>( std::declval<I>(), std::declval<S>(), std::declval<bool &>(), std::declval<int &>(), std::declval<ErrorHandler const &>(), std::declval<detail::nope &>(), std::declval<detail::symbol_table_tries_t &>(), std::declval<detail::pending_symbol_table_operations_t &>())); template<typename T, typename I, typename S, typename GlobalState> concept error_handler = requires ( T const & t, I first, S last, parse_error<I> const & e, diagnostic_kind kind, std::string_view message, minimal_parse_context< I, S, T, GlobalState> const & context) { { t(first, last, e) } -> std::same_as<error_handler_result>; t.diagnose(kind, message, context, first); t.diagnose(kind, message, context); }; template<typename T> concept container = std::ranges::common_range<T> && requires(T t) { { t.insert(t.begin(), *t.begin()) } -> std::same_as<std::ranges::iterator_t<T>>; };