std::range-default-formatter<std::range_format::map>

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Execution support library (C++26)

Technical specifications

Symbols index

External libraries

 

Utilities library

Language support Type support (basic types, RTTI) Library feature-test macros (C++20) Dynamic memory management Program utilities Coroutine support (C++20) Variadic functions is_constant_evaluated (C++20) is_within_lifetime (C++26) initializer_list (C++11) source_location (C++20) Three-way comparison three_way_comparablethree_way_comparable_with (C++20)(C++20) strong_ordering (C++20) weak_ordering (C++20) partial_ordering (C++20) common_comparison_category (C++20) compare_three_way_result (C++20) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20)   is_eqis_ltis_lteq (C++20)(C++20)(C++20)   is_neqis_gtis_gteq (C++20)(C++20)(C++20)

General utilities Date and time Function objects Formatting library (C++20)   bitset hash (C++11) Relational operators (deprecated in C++20) rel_ops::operator!=rel_ops::operator>    rel_ops::operator<=rel_ops::operator>= Integer comparison functions cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)   cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) Swap and type operations swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) Common vocabulary types pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17) to_chars_result (C++17) from_chars_result (C++17)

 

Formatting library

Standard format specification

Formatting functions

format (C++20)

format_to (C++20)

format_to_n (C++20)

formatted_size (C++20)

vformat (C++20)

vformat_to (C++20)

Format strings

basic_format_stringformat_stringwformat_string (C++20)(C++20)(C++20)

runtime_format (C++26)

Formatting concepts

formattable (C++23)

Formatter

formatter (C++20)

formatter<pair-or-tuple> (C++23)

formatter<range> (C++23)

range_formatter (C++23)

enable_nonlocking_formatter_optimization (C++23)

basic_format_parse_contextformat_parse_contextwformat_parse_context (C++20)(C++20)(C++20)

basic_format_contextformat_contextwformat_context (C++20)(C++20)(C++20)

range_format (C++23)

format_kind (C++23)

Formatting arguments

basic_format_arg (C++20)

basic_format_arg::handle (C++20)

basic_format_argsformat_argswformat_args (C++20)(C++20)(C++20)

visit_format_arg (C++20) (deprecated in C++26)

make_format_argsmake_wformat_args (C++20)(C++20)

Format error

format_error (C++20)

 

std::formatter<range>

range-default-formatter specializations

range-default-formatter<std::range_format::sequence>

range-default-formatter<std::range_format::map>

range-default-formatter<std::range_format::set>

range-default-formatter<std::range_format::string> range-default-formatter<std::range_format::debug_string>

 

Defined in header <format>
template< ranges::input_range R, class CharT > struct range-default-formatter<range_format::map, R, CharT>;		(since C++23) (exposition only*)

The class template range-default-formatter for range types is specialized for formatting range as a map of keys to values if std::format_kind<R> is std::range_format::map.

Member types

Member type	Definition
maybe-const-map (private)	/*fmt-maybe-const*/<R, CharT> (exposition-only member type*)
element-type (private)	std::remove_cvref_t<ranges::range_reference_t<maybe-const-map>>

Member objects

Member name	Definition
underlying_ (private)	the underlying formatter of type std::range_formatter<element-type, CharT> (exposition-only member object*)

Member functions

(constructor)	constructs a range-default-formatter (public member function)
parse	parses the format specifier as specified by range-format-spec (public member function)
format	writes the range formatted output as specified by range-format-spec (public member function)

std::range-default-formatter<std::range_format::map>::range-default-formatter

constexpr range-default-formatter();

Equivalent to: underlying_.set_brackets(STATICALLY_WIDEN<CharT>("{"), STATICALLY_WIDEN<CharT>("}"));
underlying_.underlying().set_brackets({}, {});
underlying_.underlying().set_separator(STATICALLY-WIDEN<charT>(": "));

where STATICALLY_WIDEN<CharT>("...") is "..." if CharT is char, and L"..." if CharT is wchar_t.

The program is ill-formed unless:

• element-type is a specialization of std::pair, or
• element-type is a specialization of std::tuple and std::tuple_size_v<element-type> is 2.

std::range-default-formatter<std::range_format::map>::parse

template< class ParseContext > constexpr auto parse( ParseContext& ctx ) -> typename ParseContext::iterator;

Equivalent to return underlying_.parse(ctx);.

Returns an iterator past the end of the range-format-spec.

std::range-default-formatter<std::range_format::map>::format

template< class FormatContext > auto format( maybe-const-map& r, FormatContext& ctx ) const     -> typename FormatContext::iterator;

Equivalent to return underlying_.format(r, ctx);.

Returns an iterator past the end of the output range.

See also

formatter (C++20)	defines formatting rules for a given type (class template)
range_formatter (C++23)	class template that helps implementing std::formatter specializations for range types (class template)