std::optional<T>::reset

void reset() noexcept;
 (since C++17)

If *this contains a value, destroy that value as if by value().T::~T(). Otherwise, there are no effects.

*this does not contain a value after this call.

See also

assigns contents
(public member function)

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/utility/optional/reset