std::visit_format_arg

 

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formatter (C++20)

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

Formatting arguments

basic_format_arg (C++20)

basic_format_argsformat_argswformat_argsformat_args_t (C++20)(C++20)(C++20)(C++20)

visit_format_arg (C++20)

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)

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.