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std::visit_format_arg

From cppreference.com
< cpp‎ | utility‎ | format
 
 
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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.

Contents

[edit] Parameters

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

[edit] Return value

The value returned by the selected invocation of the visitor.

[edit] Notes

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

[edit] Example

[edit] See also

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