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CXXLSTD, Function Objects, unary_function

 *Conan The Librarian

 			   Standard C++	Library
 		 Copyright 1996, Rogue Wave Software, Inc.

 NAME

   unary_function  - 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
   algorithms, 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 provides 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 provide the
   typedefs argument_type and result_type.  The	unary_function class
   makes  the task of creating	templated 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.

 STANDARDS CONFORMANCE
   ANSI X3J16/ISO WG21 Joint C++	Committee
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