std::mem_fun_ref_t, std::mem_fun1_ref_t, std::const_mem_fun_ref_t, std::const_mem_fun1_ref_t
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                    < cpp | utility | functional
                    
                                                            
                    | template< class S, class T >  class mem_fun_ref_t : public unary_function<T,S> { | (1) | (until C++17) (deprecated since C++11) | 
| template< class S, class T >  class const_mem_fun_ref_t : public unary_function<T,S> { | (2) | (until C++17) (deprecated since C++11) | 
| template< class S, class T, class A >  class mem_fun1_ref_t : public binary_function<T,A,S> { | (3) | (until C++17) (deprecated since C++11) | 
| template< class S, class T, class A >  class const_mem_fun1_ref_t : public binary_function<T,A,S> { | (4) | (until C++17) (deprecated since C++11) | 
Wrapper around a member function pointer. The class instance whose member function to call is passed as a reference 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.
[edit] See also
| (until C++17) | creates a wrapper from a pointer to member function, callable with a reference to object (function template) | 
| (until C++17)(until C++17)(until C++17)(until C++17) | wrapper for a pointer to nullary or unary member function, callable with a pointer to object (class template) |