std::formatter<range>

 

C++

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Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

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Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

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Filesystem library (C++17)

Regular expressions library (C++11)

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Execution support library (C++26)

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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 >     requires (std::format_kind<R> != std::range_format::disabled) &&               std::formattable<ranges::range_reference_t<R>, CharT> struct formatter<R, CharT>;		(since C++23)
Helper templates
template< std::range_format K, ranges::input_range R, class CharT > struct /*range-default-formatter*/;		(exposition only*)

The template specialization of std::formatter for the range types allows users to convert a range to its textual representation as a collection of elements or a string using formatting functions.

The specialization is derived from range-default-formatter<std::format_kind<R>, R, CharT>.

The specialization is enabled if R satisfies input_range, std::format_kind<R> is not std::range_format::disabled, and std::formattable<ranges::range_reference_t<R>, CharT> is true.

This specialization meets the Formatter requirements if const R models input_range and ranges::range_reference_t<const R> models std::formattable<CharT>. It always meets the BasicFormatter requirements.

Format specification

The syntax of range-format-spec is:

range-fill-and-align (optional) width (optional) n(optional) range-type (optional) range-underlying-spec (optional)

The syntax is fully described in range format specification.

For specializations of std::formatter where std::format_kind<R> is either std::range_format::string or std::range_format::debug_string, the format-spec is std-format-spec instead of range-format-spec (which uses std::formatter<std::basic_string<CharT>, CharT> as the underlying formatter).

Specializations of range-default-formatter

range-default-formatter<std::range_format::sequence> (C++23)	formatting utility for ranges in sequence form (class template specialization)
range-default-formatter<std::range_format::map> (C++23)	formatting utility for ranges in map form (class template specialization)
range-default-formatter<std::range_format::set> (C++23)	formatting utility for ranges in set form (class template specialization)
range-default-formatter<std::range_format::string>range-default-formatter<std::range_format::debug_string> (C++23)	formatting utility for ranges in string or escaped string form (class template specialization)

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)