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			735 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			735 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C++
		
	
	
	
| // Functor implementations -*- C++ -*-
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| 
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| // Copyright (C) 2001, 2002 Free Software Foundation, Inc.
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| //
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| // This file is part of the GNU ISO C++ Library.  This library is free
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| // software; you can redistribute it and/or modify it under the
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| // terms of the GNU General Public License as published by the
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| // Free Software Foundation; either version 2, or (at your option)
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| // any later version.
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| 
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| // This library is distributed in the hope that it will be useful,
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| // but WITHOUT ANY WARRANTY; without even the implied warranty of
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| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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| // GNU General Public License for more details.
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| 
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| // You should have received a copy of the GNU General Public License along
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| // with this library; see the file COPYING.  If not, write to the Free
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| // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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| // USA.
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| 
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| // As a special exception, you may use this file as part of a free software
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| // library without restriction.  Specifically, if other files instantiate
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| // templates or use macros or inline functions from this file, or you compile
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| // this file and link it with other files to produce an executable, this
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| // file does not by itself cause the resulting executable to be covered by
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| // the GNU General Public License.  This exception does not however
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| // invalidate any other reasons why the executable file might be covered by
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| // the GNU General Public License.
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| 
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| /*
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|  *
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|  * Copyright (c) 1994
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|  * Hewlett-Packard Company
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|  *
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|  * Permission to use, copy, modify, distribute and sell this software
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|  * and its documentation for any purpose is hereby granted without fee,
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|  * provided that the above copyright notice appear in all copies and
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|  * that both that copyright notice and this permission notice appear
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|  * in supporting documentation.  Hewlett-Packard Company makes no
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|  * representations about the suitability of this software for any
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|  * purpose.  It is provided "as is" without express or implied warranty.
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|  *
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|  *
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|  * Copyright (c) 1996-1998
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|  * Silicon Graphics Computer Systems, Inc.
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|  *
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|  * Permission to use, copy, modify, distribute and sell this software
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|  * and its documentation for any purpose is hereby granted without fee,
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|  * provided that the above copyright notice appear in all copies and
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|  * that both that copyright notice and this permission notice appear
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|  * in supporting documentation.  Silicon Graphics makes no
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|  * representations about the suitability of this software for any
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|  * purpose.  It is provided "as is" without express or implied warranty.
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|  */
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| 
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| /** @file stl_function.h
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|  *  This is an internal header file, included by other library headers.
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|  *  You should not attempt to use it directly.
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|  */
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| 
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| #ifndef _FUNCTION_H
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| #define _FUNCTION_H 1
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| 
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| namespace std
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| {
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| // 20.3.1 base classes
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| /** @defgroup s20_3_1_base Functor Base Classes
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|  *  Function objects, or @e functors, are objects with an @c operator()
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|  *  defined and accessible.  They can be passed as arguments to algorithm
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|  *  templates and used in place of a function pointer.  Not only is the
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|  *  resulting expressiveness of the library increased, but the generated
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|  *  code can be more efficient than what you might write by hand.  When we
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|  *  refer to "functors," then, generally we include function pointers in
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|  *  the description as well.
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|  *
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|  *  Often, functors are only created as temporaries passed to algorithm
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|  *  calls, rather than being created as named variables.
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|  *
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|  *  Two examples taken from the standard itself follow.  To perform a
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|  *  by-element addition of two vectors @c a and @c b containing @c double,
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|  *  and put the result in @c a, use
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|  *  \code
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|  *  transform (a.begin(), a.end(), b.begin(), a.begin(), plus<double>());
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|  *  \endcode
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|  *  To negate every element in @c a, use
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|  *  \code
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|  *  transform(a.begin(), a.end(), a.begin(), negate<double>());
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|  *  \endcode
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|  *  The addition and negation functions will be inlined directly.
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|  *
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|  *  The standard functiors are derived from structs named @c unary_function
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|  *  and @c binary_function.  These two classes contain nothing but typedefs,
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|  *  to aid in generic (template) programming.  If you write your own
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|  *  functors, you might consider doing the same.
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|  *
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|  *  @{
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| */
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| /**
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|  *  This is one of the @link s20_3_1_base functor base classes@endlink.
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| */
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| template <class _Arg, class _Result>
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| struct unary_function {
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|   typedef _Arg argument_type;   ///< @c argument_type is the type of the argument (no surprises here)
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|   typedef _Result result_type;  ///< @c result_type is the return type
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| };
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| 
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| /**
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|  *  This is one of the @link s20_3_1_base functor base classes@endlink.
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| */
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| template <class _Arg1, class _Arg2, class _Result>
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| struct binary_function {
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|   typedef _Arg1 first_argument_type;   ///< the type of the first argument (no surprises here)
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|   typedef _Arg2 second_argument_type;  ///< the type of the second argument
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|   typedef _Result result_type;         ///< type of the return type
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| };      
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| /** @}  */
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| 
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| // 20.3.2 arithmetic
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| /** @defgroup s20_3_2_arithmetic Arithmetic Classes
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|  *  Because basic math often needs to be done during an algorithm, the library
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|  *  provides functors for those operations.  See the documentation for
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|  *  @link s20_3_1_base the base classes@endlink for examples of their use.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct plus : public binary_function<_Tp,_Tp,_Tp> {
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|   _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x + __y; }
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| };
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| 
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct minus : public binary_function<_Tp,_Tp,_Tp> {
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|   _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x - __y; }
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| };
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| 
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct multiplies : public binary_function<_Tp,_Tp,_Tp> {
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|   _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x * __y; }
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| };
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| 
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct divides : public binary_function<_Tp,_Tp,_Tp> {
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|   _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x / __y; }
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| };
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| 
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct modulus : public binary_function<_Tp,_Tp,_Tp> 
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| {
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|   _Tp operator()(const _Tp& __x, const _Tp& __y) const { return __x % __y; }
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| };
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| 
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| /// One of the @link s20_3_2_arithmetic math functors@endlink.
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| template <class _Tp>
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| struct negate : public unary_function<_Tp,_Tp> 
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| {
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|   _Tp operator()(const _Tp& __x) const { return -__x; }
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| };
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| /** @}  */
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| 
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| // 20.3.3 comparisons
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| /** @defgroup s20_3_3_comparisons Comparison Classes
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|  *  The library provides six wrapper functors for all the basic comparisons
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|  *  in C++, like @c <.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct equal_to : public binary_function<_Tp,_Tp,bool> 
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x == __y; }
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| };
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| 
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct not_equal_to : public binary_function<_Tp,_Tp,bool> 
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x != __y; }
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| };
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| 
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct greater : public binary_function<_Tp,_Tp,bool> 
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x > __y; }
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| };
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| 
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct less : public binary_function<_Tp,_Tp,bool> 
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x < __y; }
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| };
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| 
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct greater_equal : public binary_function<_Tp,_Tp,bool>
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x >= __y; }
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| };
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| 
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| /// One of the @link s20_3_3_comparisons comparison functors@endlink.
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| template <class _Tp>
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| struct less_equal : public binary_function<_Tp,_Tp,bool> 
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x <= __y; }
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| };
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| /** @}  */
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| 
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| // 20.3.4 logical operations
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| /** @defgroup s20_3_4_logical Boolean Operations Classes
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|  *  Here are wrapper functors for Boolean operations:  @c &&, @c ||, and @c !.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_4_logical Boolean operations functors@endlink.
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| template <class _Tp>
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| struct logical_and : public binary_function<_Tp,_Tp,bool>
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x && __y; }
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| };
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| 
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| /// One of the @link s20_3_4_logical Boolean operations functors@endlink.
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| template <class _Tp>
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| struct logical_or : public binary_function<_Tp,_Tp,bool>
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| {
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|   bool operator()(const _Tp& __x, const _Tp& __y) const { return __x || __y; }
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| };
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| 
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| /// One of the @link s20_3_4_logical Boolean operations functors@endlink.
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| template <class _Tp>
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| struct logical_not : public unary_function<_Tp,bool>
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| {
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|   bool operator()(const _Tp& __x) const { return !__x; }
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| };
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| /** @}  */
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| 
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| // 20.3.5 negators
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| /** @defgroup s20_3_5_negators Negators
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|  *  The functions @c not1 and @c not2 each take a predicate functor
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|  *  and return an instance of @c unary_negate or
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|  *  @c binary_negate, respectively.  These classes are functors whose
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|  *  @c operator() performs the stored predicate function and then returns
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|  *  the negation of the result.
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|  *
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|  *  For example, given a vector of integers and a trivial predicate,
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|  *  \code
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|  *  struct IntGreaterThanThree
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|  *    : public std::unary_function<int, bool>
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|  *  {
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|  *      bool operator() (int x) { return x > 3; }
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|  *  };
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|  *  
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|  *  std::find_if (v.begin(), v.end(), not1(IntGreaterThanThree()));
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|  *  \endcode
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|  *  The call to @c find_if will locate the first index (i) of @c v for which
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|  *  "!(v[i] > 3)" is true.
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|  *
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|  *  The not1/unary_negate combination works on predicates taking a single
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|  *  argument.  The not2/binary_negate combination works on predicates which
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|  *  take two arguments.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_5_negators negation functors@endlink.
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| template <class _Predicate>
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| class unary_negate
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|   : public unary_function<typename _Predicate::argument_type, bool> {
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| protected:
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|   _Predicate _M_pred;
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| public:
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|   explicit unary_negate(const _Predicate& __x) : _M_pred(__x) {}
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|   bool operator()(const typename _Predicate::argument_type& __x) const {
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|     return !_M_pred(__x);
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|   }
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| };
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| 
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| /// One of the @link s20_3_5_negators negation functors@endlink.
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| template <class _Predicate>
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| inline unary_negate<_Predicate> 
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| not1(const _Predicate& __pred)
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| {
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|   return unary_negate<_Predicate>(__pred);
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| }
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| 
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| /// One of the @link s20_3_5_negators negation functors@endlink.
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| template <class _Predicate> 
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| class binary_negate 
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|   : public binary_function<typename _Predicate::first_argument_type,
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|                            typename _Predicate::second_argument_type,
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|                            bool> {
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| protected:
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|   _Predicate _M_pred;
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| public:
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|   explicit binary_negate(const _Predicate& __x) : _M_pred(__x) {}
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|   bool operator()(const typename _Predicate::first_argument_type& __x, 
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|                   const typename _Predicate::second_argument_type& __y) const
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|   {
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|     return !_M_pred(__x, __y); 
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|   }
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| };
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| 
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| /// One of the @link s20_3_5_negators negation functors@endlink.
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| template <class _Predicate>
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| inline binary_negate<_Predicate> 
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| not2(const _Predicate& __pred)
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| {
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|   return binary_negate<_Predicate>(__pred);
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| }
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| /** @}  */
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| 
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| // 20.3.6 binders
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| /** @defgroup s20_3_6_binder Binder Classes
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|  *  Binders turn functions/functors with two arguments into functors with
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|  *  a single argument, storing an argument to be applied later.  For
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|  *  example, an variable @c B of type @c binder1st is constructed from a functor
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|  *  @c f and an argument @c x.  Later, B's @c operator() is called with a
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|  *  single argument @c y.  The return value is the value of @c f(x,y).
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|  *  @c B can be "called" with various arguments (y1, y2, ...) and will in
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|  *  turn call @c f(x,y1), @c f(x,y2), ...
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|  *
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|  *  The function @c bind1st is provided to save some typing.  It takes the
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|  *  function and an argument as parameters, and returns an instance of
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|  *  @c binder1st.
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|  *
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|  *  The type @c binder2nd and its creator function @c bind2nd do the same
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|  *  thing, but the stored argument is passed as the second parameter instead
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|  *  of the first, e.g., @c bind2nd(std::minus<float>,1.3) will create a
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|  *  functor whose @c operator() accepts a floating-point number, subtracts
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|  *  1.3 from it, and returns the result.  (If @c bind1st had been used,
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|  *  the functor would perform "1.3 - x" instead.
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|  *
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|  *  Creator-wrapper functions like @c bind1st are intended to be used in
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|  *  calling algorithms.  Their return values will be temporary objects.
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|  *  (The goal is to not require you to type names like
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|  *  @c std::binder1st<std::plus<int>> for declaring a variable to hold the
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|  *  return value from @c bind1st(std::plus<int>,5).
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|  *
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|  *  These become more useful when combined with the composition functions.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_6_binder binder functors@endlink.
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| template <class _Operation> 
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| class binder1st
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|   : public unary_function<typename _Operation::second_argument_type,
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|                           typename _Operation::result_type> {
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| protected:
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|   _Operation op;
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|   typename _Operation::first_argument_type value;
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| public:
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|   binder1st(const _Operation& __x,
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|             const typename _Operation::first_argument_type& __y)
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|       : op(__x), value(__y) {}
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|   typename _Operation::result_type
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|   operator()(const typename _Operation::second_argument_type& __x) const {
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|     return op(value, __x); 
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|   }
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|   // _GLIBCXX_RESOLVE_LIB_DEFECTS
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|   // 109.  Missing binders for non-const sequence elements
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|   typename _Operation::result_type
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|   operator()(typename _Operation::second_argument_type& __x) const {
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|     return op(value, __x); 
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|   }
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| };
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| 
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| /// One of the @link s20_3_6_binder binder functors@endlink.
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| template <class _Operation, class _Tp>
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| inline binder1st<_Operation> 
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| bind1st(const _Operation& __fn, const _Tp& __x) 
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| {
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|   typedef typename _Operation::first_argument_type _Arg1_type;
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|   return binder1st<_Operation>(__fn, _Arg1_type(__x));
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| }
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| 
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| /// One of the @link s20_3_6_binder binder functors@endlink.
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| template <class _Operation> 
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| class binder2nd
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|   : public unary_function<typename _Operation::first_argument_type,
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|                           typename _Operation::result_type> {
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| protected:
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|   _Operation op;
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|   typename _Operation::second_argument_type value;
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| public:
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|   binder2nd(const _Operation& __x,
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|             const typename _Operation::second_argument_type& __y) 
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|       : op(__x), value(__y) {}
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|   typename _Operation::result_type
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|   operator()(const typename _Operation::first_argument_type& __x) const {
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|     return op(__x, value); 
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|   }
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|   // _GLIBCXX_RESOLVE_LIB_DEFECTS
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|   // 109.  Missing binders for non-const sequence elements
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|   typename _Operation::result_type
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|   operator()(typename _Operation::first_argument_type& __x) const {
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|     return op(__x, value); 
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|   }
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| };
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| 
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| /// One of the @link s20_3_6_binder binder functors@endlink.
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| template <class _Operation, class _Tp>
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| inline binder2nd<_Operation> 
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| bind2nd(const _Operation& __fn, const _Tp& __x) 
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| {
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|   typedef typename _Operation::second_argument_type _Arg2_type;
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|   return binder2nd<_Operation>(__fn, _Arg2_type(__x));
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| }
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| /** @}  */
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| 
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| // 20.3.7 adaptors pointers functions
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| /** @defgroup s20_3_7_adaptors Adaptors for pointers to functions
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|  *  The advantage of function objects over pointers to functions is that
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|  *  the objects in the standard library declare nested typedefs describing
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|  *  their argument and result types with uniform names (e.g., @c result_type
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|  *  from the base classes @c unary_function and @c binary_function).
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|  *  Sometimes those typedefs are required, not just optional.
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|  *
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|  *  Adaptors are provided to turn pointers to unary (single-argument) and
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|  *  binary (double-argument) functions into function objects.  The long-winded
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|  *  functor @c pointer_to_unary_function is constructed with a function
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|  *  pointer @c f, and its @c operator() called with argument @c x returns
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|  *  @c f(x).  The functor @c pointer_to_binary_function does the same thing,
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|  *  but with a double-argument @c f and @c operator().
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|  *
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|  *  The function @c ptr_fun takes a pointer-to-function @c f and constructs
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|  *  an instance of the appropriate functor.
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|  *
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|  *  @{
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| */
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| /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink.
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| template <class _Arg, class _Result>
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| class pointer_to_unary_function : public unary_function<_Arg, _Result> {
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| protected:
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|   _Result (*_M_ptr)(_Arg);
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| public:
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|   pointer_to_unary_function() {}
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|   explicit pointer_to_unary_function(_Result (*__x)(_Arg)) : _M_ptr(__x) {}
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|   _Result operator()(_Arg __x) const { return _M_ptr(__x); }
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| };
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| 
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| /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink.
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| template <class _Arg, class _Result>
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| inline pointer_to_unary_function<_Arg, _Result> ptr_fun(_Result (*__x)(_Arg))
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| {
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|   return pointer_to_unary_function<_Arg, _Result>(__x);
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| }
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| 
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| /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink.
 | |
| template <class _Arg1, class _Arg2, class _Result>
 | |
| class pointer_to_binary_function : 
 | |
|   public binary_function<_Arg1,_Arg2,_Result> {
 | |
| protected:
 | |
|     _Result (*_M_ptr)(_Arg1, _Arg2);
 | |
| public:
 | |
|     pointer_to_binary_function() {}
 | |
|     explicit pointer_to_binary_function(_Result (*__x)(_Arg1, _Arg2)) 
 | |
|       : _M_ptr(__x) {}
 | |
|     _Result operator()(_Arg1 __x, _Arg2 __y) const {
 | |
|       return _M_ptr(__x, __y);
 | |
|     }
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_7_adaptors adaptors for function pointers@endlink.
 | |
| template <class _Arg1, class _Arg2, class _Result>
 | |
| inline pointer_to_binary_function<_Arg1,_Arg2,_Result> 
 | |
| ptr_fun(_Result (*__x)(_Arg1, _Arg2)) {
 | |
|   return pointer_to_binary_function<_Arg1,_Arg2,_Result>(__x);
 | |
| }
 | |
| /** @}  */
 | |
| 
 | |
| template <class _Tp>
 | |
| struct _Identity : public unary_function<_Tp,_Tp> {
 | |
|   _Tp& operator()(_Tp& __x) const { return __x; }
 | |
|   const _Tp& operator()(const _Tp& __x) const { return __x; }
 | |
| };
 | |
| 
 | |
| template <class _Pair>
 | |
| struct _Select1st : public unary_function<_Pair, typename _Pair::first_type> {
 | |
|   typename _Pair::first_type& operator()(_Pair& __x) const {
 | |
|     return __x.first;
 | |
|   }
 | |
|   const typename _Pair::first_type& operator()(const _Pair& __x) const {
 | |
|     return __x.first;
 | |
|   }
 | |
| };
 | |
| 
 | |
| template <class _Pair>
 | |
| struct _Select2nd : public unary_function<_Pair, typename _Pair::second_type>
 | |
| {
 | |
|   typename _Pair::second_type& operator()(_Pair& __x) const {
 | |
|     return __x.second;
 | |
|   }
 | |
|   const typename _Pair::second_type& operator()(const _Pair& __x) const {
 | |
|     return __x.second;
 | |
|   }
 | |
| };
 | |
| 
 | |
| // 20.3.8 adaptors pointers members
 | |
| /** @defgroup s20_3_8_memadaptors Adaptors for pointers to members
 | |
|  *  There are a total of 16 = 2^4 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) Member function with void return type vs member function with
 | |
|  *       non-void return type.
 | |
|  *   (4) Const vs non-const member function.
 | |
|  *
 | |
|  *  Note that choice (3) is nothing more than a workaround: according
 | |
|  *   to the draft, compilers should handle void and non-void the same way.
 | |
|  *   This feature is not yet widely implemented, though.  You can only use
 | |
|  *   member functions returning void if your compiler supports partial
 | |
|  *   specialization.
 | |
|  *
 | |
|  *  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.
 | |
|  *
 | |
|  *  @{
 | |
| */
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp>
 | |
| class mem_fun_t : public unary_function<_Tp*,_Ret> {
 | |
| public:
 | |
|   explicit mem_fun_t(_Ret (_Tp::*__pf)()) : _M_f(__pf) {}
 | |
|   _Ret operator()(_Tp* __p) const { return (__p->*_M_f)(); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)();
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp>
 | |
| class const_mem_fun_t : public unary_function<const _Tp*,_Ret> {
 | |
| public:
 | |
|   explicit const_mem_fun_t(_Ret (_Tp::*__pf)() const) : _M_f(__pf) {}
 | |
|   _Ret operator()(const _Tp* __p) const { return (__p->*_M_f)(); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)() const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp>
 | |
| class mem_fun_ref_t : public unary_function<_Tp,_Ret> {
 | |
| public:
 | |
|   explicit mem_fun_ref_t(_Ret (_Tp::*__pf)()) : _M_f(__pf) {}
 | |
|   _Ret operator()(_Tp& __r) const { return (__r.*_M_f)(); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)();
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp>
 | |
| class const_mem_fun_ref_t : public unary_function<_Tp,_Ret> {
 | |
| public:
 | |
|   explicit const_mem_fun_ref_t(_Ret (_Tp::*__pf)() const) : _M_f(__pf) {}
 | |
|   _Ret operator()(const _Tp& __r) const { return (__r.*_M_f)(); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)() const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| class mem_fun1_t : public binary_function<_Tp*,_Arg,_Ret> {
 | |
| public:
 | |
|   explicit mem_fun1_t(_Ret (_Tp::*__pf)(_Arg)) : _M_f(__pf) {}
 | |
|   _Ret operator()(_Tp* __p, _Arg __x) const { return (__p->*_M_f)(__x); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)(_Arg);
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| class const_mem_fun1_t : public binary_function<const _Tp*,_Arg,_Ret> {
 | |
| public:
 | |
|   explicit const_mem_fun1_t(_Ret (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {}
 | |
|   _Ret operator()(const _Tp* __p, _Arg __x) const
 | |
|     { return (__p->*_M_f)(__x); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)(_Arg) const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| class mem_fun1_ref_t : public binary_function<_Tp,_Arg,_Ret> {
 | |
| public:
 | |
|   explicit mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg)) : _M_f(__pf) {}
 | |
|   _Ret operator()(_Tp& __r, _Arg __x) const { return (__r.*_M_f)(__x); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)(_Arg);
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| class const_mem_fun1_ref_t : public binary_function<_Tp,_Arg,_Ret> {
 | |
| public:
 | |
|   explicit const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {}
 | |
|   _Ret operator()(const _Tp& __r, _Arg __x) const { return (__r.*_M_f)(__x); }
 | |
| private:
 | |
|   _Ret (_Tp::*_M_f)(_Arg) const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp>
 | |
| class mem_fun_t<void, _Tp> : public unary_function<_Tp*,void> {
 | |
| public:
 | |
|   explicit mem_fun_t(void (_Tp::*__pf)()) : _M_f(__pf) {}
 | |
|   void operator()(_Tp* __p) const { (__p->*_M_f)(); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)();
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp>
 | |
| class const_mem_fun_t<void, _Tp> : public unary_function<const _Tp*,void> {
 | |
| public:
 | |
|   explicit const_mem_fun_t(void (_Tp::*__pf)() const) : _M_f(__pf) {}
 | |
|   void operator()(const _Tp* __p) const { (__p->*_M_f)(); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)() const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp>
 | |
| class mem_fun_ref_t<void, _Tp> : public unary_function<_Tp,void> {
 | |
| public:
 | |
|   explicit mem_fun_ref_t(void (_Tp::*__pf)()) : _M_f(__pf) {}
 | |
|   void operator()(_Tp& __r) const { (__r.*_M_f)(); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)();
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp>
 | |
| class const_mem_fun_ref_t<void, _Tp> : public unary_function<_Tp,void> {
 | |
| public:
 | |
|   explicit const_mem_fun_ref_t(void (_Tp::*__pf)() const) : _M_f(__pf) {}
 | |
|   void operator()(const _Tp& __r) const { (__r.*_M_f)(); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)() const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp, class _Arg>
 | |
| class mem_fun1_t<void, _Tp, _Arg> : public binary_function<_Tp*,_Arg,void> {
 | |
| public:
 | |
|   explicit mem_fun1_t(void (_Tp::*__pf)(_Arg)) : _M_f(__pf) {}
 | |
|   void operator()(_Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)(_Arg);
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp, class _Arg>
 | |
| class const_mem_fun1_t<void, _Tp, _Arg> 
 | |
|   : public binary_function<const _Tp*,_Arg,void> {
 | |
| public:
 | |
|   explicit const_mem_fun1_t(void (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {}
 | |
|   void operator()(const _Tp* __p, _Arg __x) const { (__p->*_M_f)(__x); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)(_Arg) const;
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp, class _Arg>
 | |
| class mem_fun1_ref_t<void, _Tp, _Arg>
 | |
|   : public binary_function<_Tp,_Arg,void> {
 | |
| public:
 | |
|   explicit mem_fun1_ref_t(void (_Tp::*__pf)(_Arg)) : _M_f(__pf) {}
 | |
|   void operator()(_Tp& __r, _Arg __x) const { (__r.*_M_f)(__x); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)(_Arg);
 | |
| };
 | |
| 
 | |
| /// One of the @link s20_3_8_memadaptors adaptors for member pointers@endlink.
 | |
| template <class _Tp, class _Arg>
 | |
| class const_mem_fun1_ref_t<void, _Tp, _Arg>
 | |
|   : public binary_function<_Tp,_Arg,void> {
 | |
| public:
 | |
|   explicit const_mem_fun1_ref_t(void (_Tp::*__pf)(_Arg) const) : _M_f(__pf) {}
 | |
|   void operator()(const _Tp& __r, _Arg __x) const { (__r.*_M_f)(__x); }
 | |
| private:
 | |
|   void (_Tp::*_M_f)(_Arg) const;
 | |
| };
 | |
| 
 | |
| 
 | |
| // Mem_fun adaptor helper functions.  There are only two:
 | |
| // mem_fun and mem_fun_ref.
 | |
| 
 | |
| template <class _Ret, class _Tp>
 | |
| inline mem_fun_t<_Ret,_Tp> mem_fun(_Ret (_Tp::*__f)())
 | |
|   { return mem_fun_t<_Ret,_Tp>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp>
 | |
| inline const_mem_fun_t<_Ret,_Tp> mem_fun(_Ret (_Tp::*__f)() const)
 | |
|   { return const_mem_fun_t<_Ret,_Tp>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp>
 | |
| inline mem_fun_ref_t<_Ret,_Tp> mem_fun_ref(_Ret (_Tp::*__f)()) 
 | |
|   { return mem_fun_ref_t<_Ret,_Tp>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp>
 | |
| inline const_mem_fun_ref_t<_Ret,_Tp> mem_fun_ref(_Ret (_Tp::*__f)() const)
 | |
|   { return const_mem_fun_ref_t<_Ret,_Tp>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| inline mem_fun1_t<_Ret,_Tp,_Arg> mem_fun(_Ret (_Tp::*__f)(_Arg))
 | |
|   { return mem_fun1_t<_Ret,_Tp,_Arg>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| inline const_mem_fun1_t<_Ret,_Tp,_Arg> mem_fun(_Ret (_Tp::*__f)(_Arg) const)
 | |
|   { return const_mem_fun1_t<_Ret,_Tp,_Arg>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| inline mem_fun1_ref_t<_Ret,_Tp,_Arg> mem_fun_ref(_Ret (_Tp::*__f)(_Arg))
 | |
|   { return mem_fun1_ref_t<_Ret,_Tp,_Arg>(__f); }
 | |
| 
 | |
| template <class _Ret, class _Tp, class _Arg>
 | |
| inline const_mem_fun1_ref_t<_Ret,_Tp,_Arg>
 | |
| mem_fun_ref(_Ret (_Tp::*__f)(_Arg) const)
 | |
|   { return const_mem_fun1_ref_t<_Ret,_Tp,_Arg>(__f); }
 | |
| 
 | |
| /** @}  */
 | |
| 
 | |
| } // namespace std
 | |
| 
 | |
| #endif /* _FUNCTION_H */
 | |
| 
 | |
| // Local Variables:
 | |
| // mode:C++
 | |
| // End:
 |