ptr_fun



Categories: functors adaptors	Component type: function

Prototype

template <class Arg
class Result>
pointer_to_unary_function<Arg
Result>
ptr_fun(Result (*x)(Arg));

template <class Arg1
class Arg2
class Result>
pointer_to_binary_function<Arg1
Arg2
Result>
ptr_fun(Result (*x)(Arg1
Arg2));

Description

Ptr_fun takes a function pointer as its argument and returns a function pointer adaptor a type of function object. It is actually two different functions not one (that is the name ptr_fun is overloaded). If its argument is of type Result (*)(Arg) then ptr_fun creates a pointer_to_unary_function and if its argument is of type Result (*)(Arg1 Arg2) then ptr_fun creates a pointer_to_binary_function.

Definition

Defined in the standard header functional and in the nonstandard backward-compatibility header function.h.

Requirements on types

The argument must be a pointer to a function that takes either one or two arguments. The argument type(s) and the return type of the function are arbitrary with the restriction that the function must return a value; it may not be a void function.

Preconditions

Complexity

Example

See the examples in the discussions of pointer_to_unary_function and pointer_to_binary_function.