Adaptors for pointers to members
Function Objects
Collaboration diagram for Adaptors for pointers to members:

## Classes

class | std::const_mem_fun1_ref_t< _Ret, _Tp, _Arg >
class | std::const_mem_fun1_t< _Ret, _Tp, _Arg >
class | std::const_mem_fun_ref_t< _Ret, _Tp >
class | std::const_mem_fun_t< _Ret, _Tp >
class | std::mem_fun1_ref_t< _Ret, _Tp, _Arg >
class | std::mem_fun1_t< _Ret, _Tp, _Arg >
class | std::mem_fun_ref_t< _Ret, _Tp >
class | std::mem_fun_t< _Ret, _Tp >

## Functions

template<typename _Ret , typename _Tp >
mem_fun_t< _Ret, _Tp > | std::mem_fun (_Ret(_Tp::*__f)())
template<typename _Ret , typename _Tp , typename _Arg >
mem_fun1_t< _Ret, _Tp, _Arg > | std::mem_fun (_Ret(_Tp::*__f)(_Arg))
template<typename _Ret , typename _Tp >
mem_fun_ref_t< _Ret, _Tp > | std::mem_fun_ref (_Ret(_Tp::*__f)())
template<typename _Ret , typename _Tp , typename _Arg >
mem_fun1_ref_t< _Ret, _Tp, _Arg > | std::mem_fun_ref (_Ret(_Tp::*__f)(_Arg))

## Detailed Description

There are a total of 8 = 2^3 function objects in this family. (1) Member functions taking no arguments vs member functions taking one argument. (2) Call through pointer vs call through reference. (3) Const vs non-const member function.

All of this complexity is in the function objects themselves. You can ignore it by using the helper function mem_fun and mem_fun_ref, which create whichever type of adaptor is appropriate.