std::copyable_function:: operator=

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( until C++17* )
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copyable_function & operator = ( const copyable_function & other ) ;
(1) (since C++26)
copyable_function & operator = ( copyable_function && other ) ;
(2) (since C++26)
copyable_function & operator = ( std:: nullptr_t ) noexcept ;
(3) (since C++26)
template < class F >
copyable_function & operator = ( F && f ) ;
(4) (since C++26)

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

1) Assigns a copy of the target of other to * this as if by executing auto ( other ) . swap ( * this ) .
2) 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.
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::copyable_function , as if by executing copyable_function ( std:: forward < F > ( f ) ) . swap ( * this ) ; . This overload participates in overload resolution only if the constructor of copyable_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::copyable_function object to copy or move the target of
f - a callable object to initialize the new target with

Return value

* this

Example

See also

assigns a new target
(public member function of std::function<R(Args...)> )
replaces or destroys the target
(public member function of std::move_only_function )