std::mem_fun

 

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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_tmem_fun1_tconst_mem_fun_tconst_mem_fun1_t (until C++17)(until C++17)(until C++17)(until C++17) not1 (until C++20) not2 (until C++20)	binder1stbinder2nd (until C++17)(until C++17) bind1stbind2nd (until C++17)(until C++17) mem_fun_ref (until C++17) mem_fun_ref_tmem_fun1_ref_tconst_mem_fun_ref_tconst_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 Res, class T > std::mem_fun_t<Res,T> mem_fun( Res (T::*f)() );	(1)	(deprecated in C++11) (removed in C++17)
template< class Res, class T > std::const_mem_fun_t<Res,T> mem_fun( Res (T::*f)() );	(1)	(deprecated in C++11) (removed in C++17)
template< class Res, class T, class Arg > std::mem_fun1_t<Res,T,Arg> mem_fun( Res (T::*f)(Arg) );	(2)	(deprecated in C++11) (removed in C++17)
template< class Res, class T, class Arg > std::const_mem_fun1_t<Res,T,Arg> mem_fun( S (T::*f)(Arg) );	(2)	(deprecated in C++11) (removed in C++17)

Creates a member function wrapper object, deducing the target type from the template arguments. The wrapper object expects a pointer to an object of type T as the first parameter to its operator().

1) Effectively calls std::mem_fun_t<S,T>(f) or std::const_mem_fun_t<S,T>(f).

2) Effectively calls std::mem_fun1_t<S,T>(f) or std::const_mem_fun1_t<S,T>(f).

This function and the related types were deprecated in C++11 and removed in C++17 in favor of the more general std::mem_fn and std::bind, both of which create callable adapter-compatible function objects from member functions.

Parameters

f

-

pointer to a member function to create a wrapper for

Return value

A function object wrapping f.

Exceptions

(none)

Notes

The difference between std::mem_fun and std::mem_fun_ref is that the former produces an function wrapper that expects a pointer to an object, whereas the latter -- a reference.

See also

mem_fun_ref (deprecated in C++11)(removed in C++17)

creates a wrapper from a pointer to member function, callable with a reference to object (function template)