std::holds_alternative

 

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Defined in header <variant>
template <class T, class... Types> constexpr bool holds_alternative(const std::variant<Types...>& v)		(since C++17)

Checks if the variant v holds the alternative T. The call is ill-formed if T appears more than once in Types...

Parameters

v

-

variant to examine

Return value

true if the variant currently holds the alternative T, false otherwise.

Exceptions

noexcept specification:  

noexcept