std::swap(std::optional)

 

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Defined in header <optional>
template< class T > void swap( optional<T>& lhs, optional<T>& rhs ) noexcept(/* see below */);		(since C++17)

Overloads the std::swap algorithm for std::optional. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs).

This function template does not participate in overload resolution unless std::is_move_constructible_v<T> and std::is_swappable_v<T> are both true.

Parameters

lhs, rhs

-

optional objects whose states to swap

Return value

(none)

Exceptions

noexcept specification:  

noexcept(noexcept(lhs.swap(rhs)))

See also

swap	exchanges the contents (public member function)