// Concept-checking control -*- C++ -*- 
 
// Copyright (C) 2001-2019 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 3, 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. 
 
// Under Section 7 of GPL version 3, you are granted additional 
// permissions described in the GCC Runtime Library Exception, version 
// 3.1, as published by the Free Software Foundation. 
 
// You should have received a copy of the GNU General Public License and 
// a copy of the GCC Runtime Library Exception along with this program; 
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 
// <http://www.gnu.org/licenses/>. 
 
/** @file bits/concept_check.h 
* This is an internal header file, included by other library headers. 
* Do not attempt to use it directly. @headername{iterator} 
*/ 
 
#ifndef _CONCEPT_CHECK_H 
#define _CONCEPT_CHECK_H 1 
 
#pragma GCC system_header 
 
#include <bits/c++config.h> 
 
// All places in libstdc++-v3 where these are used, or /might/ be used, or 
// don't need to be used, or perhaps /should/ be used, are commented with 
// "concept requirements" (and maybe some more text). So grep like crazy 
// if you're looking for additional places to use these. 
 
// Concept-checking code is off by default unless users turn it on via 
// configure options or editing c++config.h. 
// It is not supported for freestanding implementations. 
 
#if !defined(_GLIBCXX_CONCEPT_CHECKS) || !_GLIBCXX_HOSTED 
 
#define __glibcxx_function_requires(...) 
#define __glibcxx_class_requires(_a,_b) 
#define __glibcxx_class_requires2(_a,_b,_c) 
#define __glibcxx_class_requires3(_a,_b,_c,_d) 
#define __glibcxx_class_requires4(_a,_b,_c,_d,_e) 
 
#else // the checks are on 
 
#include <bits/boost_concept_check.h> 
 
// Note that the obvious and elegant approach of 
// 
//#define glibcxx_function_requires(C) debug::function_requires< debug::C >() 
// 
// won't work due to concept templates with more than one parameter, e.g., 
// BinaryPredicateConcept. The preprocessor tries to split things up on 
// the commas in the template argument list. We can't use an inner pair of 
// parenthesis to hide the commas, because "debug::(Temp<Foo,Bar>)" isn't 
// a valid instantiation pattern. Thus, we steal a feature from C99. 
 
#define __glibcxx_function_requires(...) \ 
__gnu_cxx::__function_requires< __gnu_cxx::__VA_ARGS__ >(); 
#define __glibcxx_class_requires(_a,_C) \ 
_GLIBCXX_CLASS_REQUIRES(_a, __gnu_cxx, _C); 
#define __glibcxx_class_requires2(_a,_b,_C) \ 
_GLIBCXX_CLASS_REQUIRES2(_a, _b, __gnu_cxx, _C); 
#define __glibcxx_class_requires3(_a,_b,_c,_C) \ 
_GLIBCXX_CLASS_REQUIRES3(_a, _b, _c, __gnu_cxx, _C); 
#define __glibcxx_class_requires4(_a,_b,_c,_d,_C) \ 
_GLIBCXX_CLASS_REQUIRES4(_a, _b, _c, _d, __gnu_cxx, _C); 
 
#endif // enable/disable 
 
#endif // _GLIBCXX_CONCEPT_CHECK