std::function

 

C++

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Utilities library

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Regular expressions library (C++11)

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Utilities library

Type support (basic types, RTTI, type traits)

Dynamic memory management

Error handling

Program utilities

Variadic functions

Date and time

Function objects

initializer_list (C++11)

bitset

hash (C++11)

Relational operators

rel_ops::operator!= rel_ops::operator> rel_ops::operator<= rel_ops::operator>=

Pairs and tuples

pair

tuple (C++11)

piecewise_construct_t (C++11)

piecewise_construct (C++11)

Swap, forward and move

swap

forward (C++11)

move (C++11)

move_if_noexcept (C++11)

declval (C++11)

 

Function objects

Operator wrappers
plus minus negate multiplies divides modulus logical_and logical_or logical_not	equal_to not_equal_to greater less greater_equal less_equal bit_and bit_or bit_xor
Negators
unary_negate binary_negate	not1 not2
Bind
bind (C++11)
is_bind_expression (C++11)
is_placeholder (C++11)
_1, _2, _3, ... (C++11)
Function wrappers
mem_fn (C++11)
function (C++11)
bad_function_call (C++11)
Reference wrappers
reference_wrapper (C++11)
ref cref (C++11) (C++11)
Deprecated binders and adaptors
unary_function (deprecated)
binary_function (deprecated)
ptr_fun (deprecated)
pointer_to_unary_function (deprecated)
pointer_to_binary_function (deprecated)
mem_fun (deprecated)
mem_fun_t mem_fun1_t const_mem_fun_t const_mem_fun1_t (deprecated) (deprecated) (deprecated) (deprecated)
mem_fun_ref (deprecated)
mem_fun_ref_t mem_fun1_ref_t const_mem_fun_ref_t const_mem_fun1_ref_t (deprecated) (deprecated) (deprecated) (deprecated)
binder1st binder2nd (deprecated) (deprecated)
bind1st bind2nd (deprecated) (deprecated)

 

std::function

Member functions

function::function

function::~function

function::operator=

function::swap

function::assign

function::operator bool

function::operator()

function::target_type

function::target

Non-member functions

operator== operator!=

std::swap(std::function)

Helper classes

std::uses_allocator<std::function>

 

Defined in header <functional>
template< class > class function; /* undefined */		(since C++11)
template< class R, class... Args > class function<R(Args...)>		(since C++11)

Class template std::function is a general-purpose polymorphic function wrapper. Instances of std::function can store, copy, and invoke any callable target -- functions, lambda expressions, bind expressions, or other function objects.

Member types

Type	Definition
result_type	R
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 functions

(constructor)	constructs a new std::function instance (public member function)
(destructor)	destroys a std::function instance (public member function)
operator=	assigns the contents (public member function)
swap	swaps the contents (public member function)
assign	assigns a new target (public member function)
operator bool	checks if a valid target is contained (public member function)
operator()	invokes the target (public member function)
Target access
target_type	obtains the typeid of the stored target of an std::function (public member function)
target	obtains a pointer to the stored target of an std::function (public member function)

Non-member functions

std::swap(std::function) (C++11)	specializes the std::swap algorithm (function template)
operator== operator!=	compares an std::function with std::nullptr (function template)

Helper classes

std::uses_allocator<std::function> (C++11)	specializes the std::uses_allocator type trait (class template specialization)

See also

bad_function_call (C++11)	the exception thrown when invoking an empty std::function (class)
mem_fn (C++11)	binds an object to a pointer to its member function to form independent function object (function template)