common.h revision 169691
1// Internal header for TR1 complex -*- C++ -*- 2 3// Copyright (C) 2006 Free Software Foundation, Inc. 4// 5// This file is part of the GNU ISO C++ Library. This library is free 6// software; you can redistribute it and/or modify it under the 7// terms of the GNU General Public License as published by the 8// Free Software Foundation; either version 2, or (at your option) 9// any later version. 10 11// This library is distributed in the hope that it will be useful, 12// but WITHOUT ANY WARRANTY; without even the implied warranty of 13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14// GNU General Public License for more details. 15 16// You should have received a copy of the GNU General Public License along 17// with this library; see the file COPYING. If not, write to the Free 18// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 19// USA. 20 21// As a special exception, you may use this file as part of a free software 22// library without restriction. Specifically, if other files instantiate 23// templates or use macros or inline functions from this file, or you compile 24// this file and link it with other files to produce an executable, this 25// file does not by itself cause the resulting executable to be covered by 26// the GNU General Public License. This exception does not however 27// invalidate any other reasons why the executable file might be covered by 28// the GNU General Public License. 29 30/** @file tr1/common.h 31 * This is a TR1 C++ Library header. 32 */ 33 34#ifndef _TR1_COMMON_H 35#define _TR1_COMMON_H 1 36 37#include <tr1/type_traits> 38 39// namespace std::tr1 40namespace std 41{ 42_GLIBCXX_BEGIN_NAMESPACE(tr1) 43 44 template<typename _Tp, bool = is_integral<_Tp>::value> 45 struct __promote 46 { typedef double __type; }; 47 48 template<typename _Tp> 49 struct __promote<_Tp, false> 50 { typedef _Tp __type; }; 51 52 template<typename _Tp, typename _Up> 53 struct __promote_2 54 { 55 private: 56 typedef typename __promote<_Tp>::__type __type1; 57 typedef typename __promote<_Up>::__type __type2; 58 59 public: 60 typedef __typeof__(__type1() + __type2()) __type; 61 }; 62 63 template<typename _Tp, typename _Up, typename _Vp> 64 struct __promote_3 65 { 66 private: 67 typedef typename __promote<_Tp>::__type __type1; 68 typedef typename __promote<_Up>::__type __type2; 69 typedef typename __promote<_Vp>::__type __type3; 70 71 public: 72 typedef __typeof__(__type1() + __type2() + __type3()) __type; 73 }; 74 75_GLIBCXX_END_NAMESPACE 76} // namespace std 77 78#endif 79