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Diffstat (limited to 'contrib/libstdc++/include/bits/cpp_type_traits.h')
| -rw-r--r-- | contrib/libstdc++/include/bits/cpp_type_traits.h | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/contrib/libstdc++/include/bits/cpp_type_traits.h b/contrib/libstdc++/include/bits/cpp_type_traits.h new file mode 100644 index 0000000..d66fe76 --- /dev/null +++ b/contrib/libstdc++/include/bits/cpp_type_traits.h @@ -0,0 +1,300 @@ +// The -*- C++ -*- type traits classes for internal use in libstdc++ + +// Copyright (C) 2000, 2001 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. + +// Written by Gabriel Dos Reis <dosreis@cmla.ens-cachan.fr> + +/** @file cpp_type_traits.h + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +#ifndef _CPP_BITS_CPP_TYPE_TRAITS_H +#define _CPP_BITS_CPP_TYPE_TRAITS_H 1 + +#pragma GCC system_header + +// +// This file provides some compile-time information about various types. +// These representations were designed, on purpose, to be constant-expressions +// and not types as found in <stl/bits/type_traits.h>. In particular, they +// can be used in control structures and the optimizer hopefully will do +// the obvious thing. +// +// Why integral expressions, and not functions nor types? +// Firstly, these compile-time entities are used as template-arguments +// so function return values won't work: We need compile-time entities. +// We're left with types and constant integral expressions. +// Secondly, from the point of view of ease of use, type-based compile-time +// information is -not- *that* convenient. On has to write lots of +// overloaded functions and to hope that the compiler will select the right +// one. As a net effect, the overall structure isn't very clear at first +// glance. +// Thirdly, partial ordering and overload resolution (of function templates) +// is highly costly in terms of compiler-resource. It is a Good Thing to +// keep these resource consumption as least as possible. +// +// See valarray_array.h for a case use. +// +// -- Gaby (dosreis@cmla.ens-cachan.fr) 2000-03-06. +// + +namespace std +{ + template<typename _Tp> + struct __is_void + { + enum + { + _M_type = 0 + }; + }; + + template<> + struct __is_void<void> + { + enum + { + _M_type = 1 + }; + }; + + // + // Integer types + // + template<typename _Tp> + struct __is_integer + { + enum + { + _M_type = 0 + }; + }; + + // Thirteen specializations (yes there are eleven standard integer + // types; 'long long' and 'unsigned long long' are supported as + // extensions) + template<> + struct __is_integer<bool> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<char> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<signed char> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<unsigned char> + { + enum + { + _M_type = 1 + }; + }; + +# ifdef _GLIBCPP_USE_WCHAR_T + template<> + struct __is_integer<wchar_t> + { + enum + { + _M_type = 1 + }; + }; +# endif + + template<> + struct __is_integer<short> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<unsigned short> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<int> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<unsigned int> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<long> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<unsigned long> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<long long> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_integer<unsigned long long> + { + enum + { + _M_type = 1 + }; + }; + + // + // Floating point types + // + template<typename _Tp> + struct __is_floating + { + enum + { + _M_type = 0 + }; + }; + + // three specializations (float, double and 'long double') + template<> + struct __is_floating<float> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_floating<double> + { + enum + { + _M_type = 1 + }; + }; + + template<> + struct __is_floating<long double> + { + enum + { + _M_type = 1 + }; + }; + + // + // An arithmetic type is an integer type or a floating point type + // + template<typename _Tp> + struct __is_arithmetic + { + enum + { + _M_type = __is_integer<_Tp>::_M_type || __is_floating<_Tp>::_M_type + }; + }; + + // + // A fundamental type is `void' or and arithmetic type + // + template<typename _Tp> + struct __is_fundamental + { + enum + { + _M_type = __is_void<_Tp>::_M_type || __is_arithmetic<_Tp>::_M_type + }; + }; + + // + // For the immediate use, the following is a good approximation + // + template<typename _Tp> + struct __is_pod + { + enum + { + _M_type = __is_fundamental<_Tp>::_M_type + }; + }; + +} // namespace std + + +#endif //_CPP_BITS_CPP_TYPE_TRAITS_H |
