std::experimental::function::function
| function(); |
(1) | (library fundamentals TS) |
| function( std::nullptr_t ); |
(2) | (library fundamentals TS) |
| function( const function& other ); |
(3) | (library fundamentals TS) |
| function( function&& other ); |
(4) | (library fundamentals TS) |
| template< class F > function( F f ); |
(5) | (library fundamentals TS) |
| template< class Alloc > function( std::allocator_arg_t, const Alloc& alloc ); |
(6) | (library fundamentals TS) |
| template< class Alloc > function( std::allocator_arg_t, const Alloc& alloc, |
(7) | (library fundamentals TS) |
| template< class Alloc > function( std::allocator_arg_t, const Alloc& alloc, |
(8) | (library fundamentals TS) |
| template< class Alloc > function( std::allocator_arg_t, const Alloc& alloc, |
(9) | (library fundamentals TS) |
| template< class F, class Alloc > function( std::allocator_arg_t, const Alloc& alloc, F f ); |
(10) | (library fundamentals TS) |
Constructs a std::experimental::function from a variety of sources.
other to the target of *this. If other is empty, *this will be empty after the call too.f. If f is a null pointer to function or null pointer to member, *this will be empty after the call. This constructor does not participate in overload resolution unless f is Callable for argument types Args... and return type R.alloc is used to allocate memory for any internal data structures that the function might use. These constructors treat alloc as a type-erased allocator (see below).When the target is a function pointer or a std::reference_wrapper, small object optimization is guaranteed, that is, these targets are always directly stored inside the std::experimental::function object, no dynamic allocation takes place. Other large objects may be constructed in dynamic allocated storage and accessed by the std::experimental::function object through a pointer.
If a constructor moves or copies a function object, including an instance of std::experimental::function, then that move or copy is performed by using-allocator construction with allocator this->get_memory_resource().
Contents |
[edit] Type-erased allocator
The constructors of function taking an allocator argument alloc treats that argument as a type-erased allocator. The memory resource pointer used by function to allocate memory is determined using the allocator argument (if specified) as follows:
Type of alloc
|
value of the memory resource pointer |
| Non-existent (no allocator specified at time of construction) | The value of std::experimental::pmr::get_default_resource() at time of construction. |
| std::nullptr_t | The value of std::experimental::pmr::get_default_resource() at time of construction |
| A pointer type convertible to std::experimental::pmr::memory_resource* |
static_cast<std::experimental::pmr::memory_resource*>(alloc) |
| A specialization of std::experimental::pmr::polymorphic_allocator |
alloc.resource() |
Any other type meeting the Allocator requirements
|
A pointer to a value of type std::experimental::pmr::resource_adaptor<A>(alloc), where A is the type of alloc. The pointer remains valid only for the lifetime of the function object.
|
| None of the above | The program is ill-formed. |
[edit] Parameters
| other | - | the function object used to initialize *this |
| f | - | a callable used to initialize *this |
| alloc | - | an allocator used for internal memory allocation |
| Type requirements | ||
-F must meet the requirements of Callable and CopyConstructible.
| ||
[edit] Exceptions
other's target is a function pointer or a std::reference_wrapper, otherwise may throw std::bad_alloc or any exception thrown by the copy constructor of the stored callable object.f is a function pointer or a std::reference_wrapper, otherwise may throw std::bad_alloc or any exception thrown by the copy constructor of the stored callable object.[edit] Example
| This section is incomplete Reason: no example |