std::move_only_function:: operator=

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std::move_only_function
move_only_function & operator = ( move_only_function && other ) ;
(1) (since C++23)
move_only_function & operator = ( const move_only_function & ) = delete ;
(2) (since C++23)
move_only_function & operator = ( std:: nullptr_t ) noexcept ;
(3) (since C++23)
template < class F >
move_only_function & operator = ( F && f ) ;
(4) (since C++23)

Assigns a new target to std::move_only_function or destroys its target.

1) Moves the target of other to * this or destroys the target of * this (if any) if other is empty, by auto ( std :: move ( other ) ) . swap ( * this ) . other is in a valid state with an unspecified value after move assignment.
2) Copy assignment operator is deleted. std::move_only_function does not satisfy CopyAssignable .
3) Destroys the current target if it exists. * this is empty after the call.
4) Sets the target of * this to the callable f , or destroys the current target if f is a null function pointer, a null pointer to member function, or an empty std::move_only_function , as if by executing move_only_function ( std:: forward < F > ( f ) ) . swap ( * this ) ; . This overload participates in overload resolution only if the constructor of move_only_function from F participates in overload resolution. The program is ill-formed or has undefined behavior if the selected constructor call is ill-formed or has undefined behavior.

Parameters

other - another std::move_only_function object to move the target of
f - a callable object to initialize the new target with

Return value

* this

Notes

It is intentional not to require the move assignment operator to be noexcept to leave room for an allocator-aware move_only_function in future.

move_only_function can be assigned from std:: in_place_type < Fn > given it can be constructed from that argument.

Example

This section is incomplete
Reason: no example

See also

assigns a new target
(public member function of std::function<R(Args...)> )
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