std::move_only_function::operator= - cppreference.com (original) (raw)
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.
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.
Copy assignment operator is deleted.
std::move_only_function
does not satisfy CopyAssignable.Destroys the current target if it exists. *this is empty after the call.
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 ofmove_only_function
fromF
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.
[edit] Parameters
other | - | another std::move_only_function object to move the target of |
---|---|---|
f | - | a callable object to initialize the new target with |
[edit] Return value
*this
[edit] 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.
[edit] Example
[edit] See also
| | assigns a new target (public member function of std::function<R(Args...)>) [edit] | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |