std:: mem_fun_t, std:: mem_fun1_t, std:: const_mem_fun_t, std:: const_mem_fun1_t

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Partial function application
bind_front bind_back (C++20) (C++23)
bind (C++11)
is_bind_expression (C++11)
is_placeholder (C++11)
_1, _2, _3, ... (C++11)

Reference wrappers
reference_wrapper (C++11)
ref cref (C++11) (C++11)
unwrap_reference unwrap_ref_decay (C++20) (C++20)

Negators
not_fn (C++17)
Searchers
default_searcher (C++17)
boyer_moore_searcher (C++17)
boyer_moore_horspool_searcher (C++17)

unary_function ( until C++17* )
binary_function ( until C++17* )
ptr_fun ( until C++17* )
pointer_to_unary_function ( until C++17* )
pointer_to_binary_function ( until C++17* )
mem_fun ( until C++17* )
mem_fun_t mem_fun1_t const_mem_fun_t const_mem_fun1_t ( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
not1 ( until C++20* )
not2 ( until C++20* )

binder1st binder2nd ( until C++17* ) ( until C++17* )
bind1st bind2nd ( until C++17* ) ( until C++17* )

mem_fun_ref ( until C++17* )
mem_fun_ref_t mem_fun1_ref_t const_mem_fun_ref_t const_mem_fun1_ref_t ( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
unary_negate ( until C++20* )
binary_negate ( until C++20* )

Defined in header `<functional>`
template < class S, class T > class mem_fun_t : public unary_function < T * ,S > { public : explicit mem_fun_t ( S ( T :: * p ) ( ) ) ; S operator ( ) ( T * p ) const ; } ;	(1)	(deprecated in C++11) (removed in C++17)
template < class S, class T > class const_mem_fun_t : public unary_function < const T * ,S > { public : explicit const_mem_fun_t ( S ( T :: * p ) ( ) const ) ; S operator ( ) ( const T * p ) const ; } ;	(2)	(deprecated in C++11) (removed in C++17)
template < class S, class T, class A > class mem_fun1_t : public binary_function < T * ,A,S > { public : explicit mem_fun1_t ( S ( T :: * p ) ( A ) ) ; S operator ( ) ( T * p, A x ) const ; } ;	(3)	(deprecated in C++11) (removed in C++17)
template < class S, class T, class A > class const_mem_fun1_t : public binary_function < const T * ,A,S > { public : explicit const_mem_fun1_t ( S ( T :: * p ) ( A ) const ) ; S operator ( ) ( const T * p, A x ) const ; } ;	(4)	(deprecated in C++11) (removed in C++17)

Wrapper around a member function pointer. The class instance whose member function to call is passed as a pointer to the operator() .

1) Wraps a non-const member function with no parameters.

2) Wraps a const member function with no parameters.

3) Wraps a non-const member function with a single parameter.

4) Wraps a const member function with a single parameter.

Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros (C++20)
Language support library
Concepts library (C++20)
Metaprogramming library (C++11)
Diagnostics library
General utilities library
Strings library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Numerics library
Localizations library
Input/output library
Filesystem library (C++17)
Regular expressions library (C++11)
Concurrency support library (C++11)
Execution support library (C++26)
Technical specifications
Symbols index
External libraries

mem_fun (deprecated in C++11) (removed in C++17)	creates a wrapper from a pointer to member function, callable with a pointer to object (function template)
mem_fun_ref_t mem_fun1_ref_t const_mem_fun_ref_t const_mem_fun1_ref_t (deprecated in C++11) (removed in C++17)	wrapper for a pointer to nullary or unary member function, callable with a reference to object (class template)