std::visit_format_arg

 

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format (C++20)

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format_to_n (C++20)

formatted_size (C++20)

vformat (C++20)

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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)

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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)

 

Defined in header <format>
template< class Visitor, class Context > /* see below */ visit_format_arg( Visitor&& vis, std::basic_format_arg<Context> arg );		(since C++20) (deprecated in C++26)

Applies the visitor vis to the object contained in arg.

Equivalent to std::visit(std::forward<Visitor>(vis), value), where value is the std::variant stored in arg.

Parameters

vis	-	a Callable that accepts every possible alternative from arg
arg	-	a std::basic_format_arg to be visited

Return value

The value returned by the selected invocation of the visitor.

Notes

As of C++26, std::visit_format_arg is deprecated in favor of the visit member functions of std::basic_format_arg.

See also

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

creates a type-erased object referencing all formatting arguments, convertible to format_args (function template)