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std::function::operator=

function& operator=( const function& other );	(1)	(since C++11)
function& operator=( function&& other );	(2)	(since C++11)
function& operator=( std::nullptr_t );	(3)	(since C++11)
template< class F > function& operator=( F&& f );	(4)	(since C++11)
template< class F > function& operator=( std::reference_wrapper<F> f );	(5)	(since C++11)

Assigns a new target to std::function.

1) Assigns a copy of target of other, as if by executing function(other).swap(*this);

2) Moves the target of other to *this. other is in a valid state with an unspecified value.

3) Drops the current target. *this is empty after the call.

4) Sets the target of *this to the callable f, as if by executing function(std::forward<F>(f)).swap(*this);. This operator does not participate in overload resolution unless f is Callable for argument types Args... and return type R. (since C++14)

5) Sets the target of *this to a copy of f, as if by executing function(f).swap(*this);

Parameters

other	-	another `std::function` object to copy the target of
f	-	a callable to initialize the target with
Type requirements
-`F` must meet the requirements of Callable.

Return value

*this.

Exceptions

1-2) (none)

(none).	(until C++17)
`noexcept` specification: `noexcept`	(since C++17)

4) (none)

noexcept specification:

noexcept

Notes

Even before allocator support was removed from std::function in C++17, these assignment operators use the default allocator rather than the allocator of *this or the allocator of other (see LWG #2386).

std::function::operator=

Parameters

Return value

Exceptions

Notes

See also