unary_function(3C++) - unary_function(3C++)
Standard C++ Library Copyright 1998, Rogue Wave Software, Inc.
NAMEunary_function
- A base class for creating unary function objects.
SYNOPSIS
#include <functional>
template <class Arg, class Result>
struct unary_function{
typedef Arg argument_type;
typedef Result result_type;
};
DESCRIPTION
Function objects are objects with an operator() defined. They are
important for the effective use of the standard library's generic algo‐
rithms, because the interface for each algorithmic template can accept
either an object with an operator() defined or a pointer to a function.
The standard library includes both a standard set of function objects
and a pair of classes that you can use as the base for creating your
own function objects.
Function objects that take one argument are called unary function
objects. Unary function objects are required to include the typedefs
argument_type and result_type. The unary_function class makes the task
of creating templatized unary function objects easier by providing the
necessary typedefs for a unary function object. You can create your own
unary function objects by inheriting from unary_function.
SEE ALSO
Function_Objects, and Function Objects Section in User's Guide.
Rogue Wave Software 02 Apr 1998 unary_function(3C++)
