std:: visit_format_arg

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Utilities library
General utilities
Relational operators (deprecated in 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 .

Example

See also

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