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 40 namespace 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