// Pair implementation -*- C++ -*- // Copyright (C) 2001, 2004 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 2, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // You should have received a copy of the GNU General Public License along // with this library; see the file COPYING. If not, write to the Free // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, // USA. // As a special exception, you may use this file as part of a free software // library without restriction. Specifically, if other files instantiate // templates or use macros or inline functions from this file, or you compile // this file and link it with other files to produce an executable, this // file does not by itself cause the resulting executable to be covered by // the GNU General Public License. This exception does not however // invalidate any other reasons why the executable file might be covered by // the GNU General Public License. /* * * Copyright (c) 1994 * Hewlett-Packard Company * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Hewlett-Packard Company makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. * * * Copyright (c) 1996,1997 * Silicon Graphics Computer Systems, Inc. * * Permission to use, copy, modify, distribute and sell this software * and its documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. Silicon Graphics makes no * representations about the suitability of this software for any * purpose. It is provided "as is" without express or implied warranty. */ /** @file stl_pair.h * This is an internal header file, included by other library headers. * You should not attempt to use it directly. */ #ifndef _PAIR_H #define _PAIR_H 1 namespace std { /// pair holds two objects of arbitrary type. template<class _T1, class _T2> struct pair { typedef _T1 first_type; ///< @c first_type is the first bound type typedef _T2 second_type; ///< @c second_type is the second bound type _T1 first; ///< @c first is a copy of the first object _T2 second; ///< @c second is a copy of the second object // _GLIBCXX_RESOLVE_LIB_DEFECTS // 265. std::pair::pair() effects overly restrictive /** The default constructor creates @c first and @c second using their * respective default constructors. */ pair() : first(), second() { } /** Two objects may be passed to a @c pair constructor to be copied. */ pair(const _T1& __a, const _T2& __b) : first(__a), second(__b) { } /** There is also a templated copy ctor for the @c pair class itself. */ template<class _U1, class _U2> pair(const pair<_U1, _U2>& __p) : first(__p.first), second(__p.second) { } }; /// Two pairs of the same type are equal iff their members are equal. template<class _T1, class _T2> inline bool operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return __x.first == __y.first && __x.second == __y.second; } /// <http://gcc.gnu.org/onlinedocs/libstdc++/20_util/howto.html#pairlt> template<class _T1, class _T2> inline bool operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return __x.first < __y.first || (!(__y.first < __x.first) && __x.second < __y.second); } /// Uses @c operator== to find the result. template<class _T1, class _T2> inline bool operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return !(__x == __y); } /// Uses @c operator< to find the result. template<class _T1, class _T2> inline bool operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return __y < __x; } /// Uses @c operator< to find the result. template<class _T1, class _T2> inline bool operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return !(__y < __x); } /// Uses @c operator< to find the result. template<class _T1, class _T2> inline bool operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) { return !(__x < __y); } /** * @brief A convenience wrapper for creating a pair from two objects. * @param x The first object. * @param y The second object. * @return A newly-constructed pair<> object of the appropriate type. * * The standard requires that the objects be passed by reference-to-const, * but LWG issue #181 says they should be passed by const value. We follow * the LWG by default. */ // _GLIBCXX_RESOLVE_LIB_DEFECTS // 181. make_pair() unintended behavior template<class _T1, class _T2> inline pair<_T1, _T2> make_pair(_T1 __x, _T2 __y) { return pair<_T1, _T2>(__x, __y); } } // namespace std #endif /* _PAIR_H */