std::experimental:: function

From cppreference.com
Defined in header <experimental/functional>
template < class >
class function ; /* undefined */
(library fundamentals TS)
template < class R, class ... Args >
class function < R ( Args... ) >
(library fundamentals TS)

std::experimental::function is a modified version of std::function with support for type-erased allocators.

Member types

Type Definition
allocator_type

std::experimental::erased_type

(library fundamentals TS)
(until library fundamentals TS v3)

std:: pmr :: polymorphic_allocator <>

(library fundamentals TS v3)

Member functions

constructs a new std::experimental::function instance
(public member function)
assigns a new target
(public member function)
swaps the contents
(public member function)
(removed in library fundamentals TS v3)
retrieves a pointer to the memory resource used by this object to allocate memory
(public member function)
(library fundamentals TS v3)
retrieves a type-erased std::pmr::polymorphic_allocator used by this object to allocate memory
(public member function)

Non-member functions

specializes the swap algorithm
(function template)
(removed in library fundamentals TS v3)
compares an std::experimental::function with nullptr
(function template)

Helper classes

(removed in library fundamentals TS v3)
specializes the std::uses_allocator type trait
(class template specialization)

Members identical to std:: function

Member types

Type Definition
result_type R
Member types removed in Library Fundamental TS v3
argument_type T if sizeof... ( Args ) == 1 and T is the first and only type in Args...
first_argument_type T1 if sizeof... ( Args ) == 2 and T1 is the first of the two types in Args...
second_argument_type T2 if sizeof... ( Args ) == 2 and T2 is the second of the two types in Args...

Member types argument_type , first_argument_type , and second_argument_type are removed, because the correponding member types of std::function are removed in C++20.

(library fundamentals TS v3)

Member functions

destroys a std::function instance
(public member function of std::function<R(Args...)> )
checks if a target is contained
(public member function of std::function<R(Args...)> )
invokes the target
(public member function of std::function<R(Args...)> )
Target access
obtains the typeid of the stored target
(public member function of std::function<R(Args...)> )
obtains a pointer to the stored target
(public member function of std::function<R(Args...)> )