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