libstdc++
concept_check.h
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00001 // Concept-checking control -*- C++ -*-
00002 
00003 // Copyright (C) 2001, 2009, 2010 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file bits/concept_check.h
00026  *  This is an internal header file, included by other library headers.
00027  *  Do not attempt to use it directly. @headername{iterator}
00028  */
00029 
00030 #ifndef _CONCEPT_CHECK_H
00031 #define _CONCEPT_CHECK_H 1
00032 
00033 #pragma GCC system_header
00034 
00035 #include <bits/c++config.h>
00036 
00037 // All places in libstdc++-v3 where these are used, or /might/ be used, or
00038 // don't need to be used, or perhaps /should/ be used, are commented with
00039 // "concept requirements" (and maybe some more text).  So grep like crazy
00040 // if you're looking for additional places to use these.
00041 
00042 // Concept-checking code is off by default unless users turn it on via
00043 // configure options or editing c++config.h.
00044 
00045 #ifndef _GLIBCXX_CONCEPT_CHECKS
00046 
00047 #define __glibcxx_function_requires(...)
00048 #define __glibcxx_class_requires(_a,_b)
00049 #define __glibcxx_class_requires2(_a,_b,_c)
00050 #define __glibcxx_class_requires3(_a,_b,_c,_d)
00051 #define __glibcxx_class_requires4(_a,_b,_c,_d,_e)
00052 
00053 #else // the checks are on
00054 
00055 #include <bits/boost_concept_check.h>
00056 
00057 // Note that the obvious and elegant approach of
00058 //
00059 //#define glibcxx_function_requires(C) boost::function_requires< boost::C >()
00060 //
00061 // won't work due to concept templates with more than one parameter, e.g.,
00062 // BinaryPredicateConcept.  The preprocessor tries to split things up on
00063 // the commas in the template argument list.  We can't use an inner pair of
00064 // parenthesis to hide the commas, because "boost::(Temp<Foo,Bar>)" isn't
00065 // a valid instantiation pattern.  Thus, we steal a feature from C99.
00066 
00067 #define __glibcxx_function_requires(...)                                 \
00068             __gnu_cxx::__function_requires< __gnu_cxx::__VA_ARGS__ >();
00069 #define __glibcxx_class_requires(_a,_C)                                  \
00070             _GLIBCXX_CLASS_REQUIRES(_a, __gnu_cxx, _C);
00071 #define __glibcxx_class_requires2(_a,_b,_C)                              \
00072             _GLIBCXX_CLASS_REQUIRES2(_a, _b, __gnu_cxx, _C);
00073 #define __glibcxx_class_requires3(_a,_b,_c,_C)                           \
00074             _GLIBCXX_CLASS_REQUIRES3(_a, _b, _c, __gnu_cxx, _C);
00075 #define __glibcxx_class_requires4(_a,_b,_c,_d,_C)                        \
00076             _GLIBCXX_CLASS_REQUIRES4(_a, _b, _c, _d, __gnu_cxx, _C);
00077 
00078 #endif // enable/disable
00079 
00080 #endif // _GLIBCXX_CONCEPT_CHECK