std::experimental::function<R(Args...)>::operator=
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< cpp | experimental | function
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function& operator=( const function& other );
(1)
(library fundamentals TS)
function& operator=( function&& other );
(2)
(library fundamentals TS)
function& operator=( std::nullptr_t ) noexcept;
(3)
(library fundamentals TS)
template< class F >
function& operator=( F&& f );
(4)
(library fundamentals TS)
function& operator=( F&& f );
(5)
template< class F >
function& operator=( std::reference_wrapper <F> f );
(library fundamentals TS)
function& operator=( std::reference_wrapper <F> f );
template< class F >
function& operator=( std::reference_wrapper <F> f ) noexcept;
(library fundamentals TS v3)
function& operator=( std::reference_wrapper <F> f ) noexcept;
Assigns a new target to std::experimental::function. In the description below, let ALLOCATOR_OF(f) be the allocator specified in the construction of f, or the value of std::experimental::pmr::get_default_resource ()(until library fundamentals TS v3)the default-constructed std::pmr::polymorphic_allocator <> value(library fundamentals TS v3) at the time of construction if no allocator was specified.
1) Assigns a copy of target of other, as if by executing function(std::allocator_arg, ALLOCATOR_OF(*this), other).swap(*this);.
2) Moves the target of other to *this, as if by executing function(std::allocator_arg, ALLOCATOR_OF(*this), std::move(other)).swap(*this);. other is in a valid state with an unspecified value.
3) Destroys the target of *this. *this is empty after the call. The memory resource returned by
get_memory_resource() after the assignment is equivalent to the memory resource before the assignment, but the address may change.4) Sets the target of *this to the callable f, as if by executing function(std::allocator_arg, ALLOCATOR_OF(*this),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.5) Sets the target of *this to a copy of f, as if by executing function(std::allocator_arg, ALLOCATOR_OF(*this), f).swap(*this);.
Contents
[edit] Parameters
other
-
another
std::experimental::function object to copy or move from
f
-
a callable to initialize the target with
Type requirements
-
F must meet the requirements of Callable.
[edit] Return value
*this
[edit] Exceptions
1,2,4) Exception thrown on needed allocation of the storage or initialization of the target of *this, if any.
5) (none)
[edit] Notes
The move assignment operator may need to allocate storage if get_memory_resource() != other.get_memory_resource()(until library fundamentals TS v3)get_allocator() != other.get_allocator()(library fundamentals TS v3)