std::promise<R>::operator=

promise& operator=( promise&& other ) noexcept;
(1) (since C++11)
promise& operator=( const promise& rhs ) = delete;
(2) (since C++11)

Assigns the contents.

1) Move assignment operator. First, abandons the shared state (as in ~promise()), then assigns the shared state of other as if by executing std::promise(std::move(other)).swap(*this).
2) promise is not copy-assignable.

Parameters

other - another promise to acquire the state from

Return value

*this.

Exceptions

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