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) | 
|   template< class F >  function& operator=( std::reference_wrapper<F> f );  | 
(5) | (library fundamentals TS) | 
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() 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);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.
 | ||
Return value
*this
Exceptions
1-2,4-5) (none)