std::experimental::function<R(Args...)>::operator=
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< cpp | experimental | function
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) |
(5) | ||
template<class F > function& operator=(std::reference_wrapper<F> f ); | (library fundamentals TS) | |
template<class F > function& operator=(std::reference_wrapper<F> f )noexcept; | (library fundamentals TS v3) | |
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)