boost_concept_check.h
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// -*- C++ -*-
// Copyright (C) 2004-2013 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/>.
// (C) Copyright Jeremy Siek 2000. Permission to copy, use, modify,
// sell and distribute this software is granted provided this
// copyright notice appears in all copies. This software is provided
// "as is" without express or implied warranty, and with no claim as
// to its suitability for any purpose.
//
/** @file bits/boost_concept_check.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{iterator}
*/
// GCC Note: based on version 1.12.0 of the Boost library.
#ifndef _BOOST_CONCEPT_CHECK_H
#define _BOOST_CONCEPT_CHECK_H 1
#pragma GCC system_header
#include <bits/c++config.h>
#include <bits/stl_iterator_base_types.h> // for traits and tags
namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#define _IsUnused __attribute__ ((__unused__))
// When the C-C code is in use, we would like this function to do as little
// as possible at runtime, use as few resources as possible, and hopefully
// be elided out of existence... hmmm.
template <class _Concept>
inline void __function_requires()
{
void (_Concept::*__x)() _IsUnused = &_Concept::__constraints;
}
// No definition: if this is referenced, there's a problem with
// the instantiating type not being one of the required integer types.
// Unfortunately, this results in a link-time error, not a compile-time error.
void __error_type_must_be_an_integer_type();
void __error_type_must_be_an_unsigned_integer_type();
void __error_type_must_be_a_signed_integer_type();
// ??? Should the "concept_checking*" structs begin with more than _ ?
#define _GLIBCXX_CLASS_REQUIRES(_type_var, _ns, _concept) \
typedef void (_ns::_concept <_type_var>::* _func##_type_var##_concept)(); \
template <_func##_type_var##_concept _Tp1> \
struct _concept_checking##_type_var##_concept { }; \
typedef _concept_checking##_type_var##_concept< \
&_ns::_concept <_type_var>::__constraints> \
_concept_checking_typedef##_type_var##_concept
#define _GLIBCXX_CLASS_REQUIRES2(_type_var1, _type_var2, _ns, _concept) \
typedef void (_ns::_concept <_type_var1,_type_var2>::* _func##_type_var1##_type_var2##_concept)(); \
template <_func##_type_var1##_type_var2##_concept _Tp1> \
struct _concept_checking##_type_var1##_type_var2##_concept { }; \
typedef _concept_checking##_type_var1##_type_var2##_concept< \
&_ns::_concept <_type_var1,_type_var2>::__constraints> \
_concept_checking_typedef##_type_var1##_type_var2##_concept
#define _GLIBCXX_CLASS_REQUIRES3(_type_var1, _type_var2, _type_var3, _ns, _concept) \
typedef void (_ns::_concept <_type_var1,_type_var2,_type_var3>::* _func##_type_var1##_type_var2##_type_var3##_concept)(); \
template <_func##_type_var1##_type_var2##_type_var3##_concept _Tp1> \
struct _concept_checking##_type_var1##_type_var2##_type_var3##_concept { }; \
typedef _concept_checking##_type_var1##_type_var2##_type_var3##_concept< \
&_ns::_concept <_type_var1,_type_var2,_type_var3>::__constraints> \
_concept_checking_typedef##_type_var1##_type_var2##_type_var3##_concept
#define _GLIBCXX_CLASS_REQUIRES4(_type_var1, _type_var2, _type_var3, _type_var4, _ns, _concept) \
typedef void (_ns::_concept <_type_var1,_type_var2,_type_var3,_type_var4>::* _func##_type_var1##_type_var2##_type_var3##_type_var4##_concept)(); \
template <_func##_type_var1##_type_var2##_type_var3##_type_var4##_concept _Tp1> \
struct _concept_checking##_type_var1##_type_var2##_type_var3##_type_var4##_concept { }; \
typedef _concept_checking##_type_var1##_type_var2##_type_var3##_type_var4##_concept< \
&_ns::_concept <_type_var1,_type_var2,_type_var3,_type_var4>::__constraints> \
_concept_checking_typedef##_type_var1##_type_var2##_type_var3##_type_var4##_concept
template <class _Tp1, class _Tp2>
struct _Aux_require_same { };
template <class _Tp>
struct _Aux_require_same<_Tp,_Tp> { typedef _Tp _Type; };
template <class _Tp1, class _Tp2>
struct _SameTypeConcept
{
void __constraints() {
typedef typename _Aux_require_same<_Tp1, _Tp2>::_Type _Required;
}
};
template <class _Tp>
struct _IntegerConcept {
void __constraints() {
__error_type_must_be_an_integer_type();
}
};
template <> struct _IntegerConcept<short> { void __constraints() {} };
template <> struct _IntegerConcept<unsigned short> { void __constraints(){} };
template <> struct _IntegerConcept<int> { void __constraints() {} };
template <> struct _IntegerConcept<unsigned int> { void __constraints() {} };
template <> struct _IntegerConcept<long> { void __constraints() {} };
template <> struct _IntegerConcept<unsigned long> { void __constraints() {} };
template <> struct _IntegerConcept<long long> { void __constraints() {} };
template <> struct _IntegerConcept<unsigned long long>
{ void __constraints() {} };
template <class _Tp>
struct _SignedIntegerConcept {
void __constraints() {
__error_type_must_be_a_signed_integer_type();
}
};
template <> struct _SignedIntegerConcept<short> { void __constraints() {} };
template <> struct _SignedIntegerConcept<int> { void __constraints() {} };
template <> struct _SignedIntegerConcept<long> { void __constraints() {} };
template <> struct _SignedIntegerConcept<long long> { void __constraints(){}};
template <class _Tp>
struct _UnsignedIntegerConcept {
void __constraints() {
__error_type_must_be_an_unsigned_integer_type();
}
};
template <> struct _UnsignedIntegerConcept<unsigned short>
{ void __constraints() {} };
template <> struct _UnsignedIntegerConcept<unsigned int>
{ void __constraints() {} };
template <> struct _UnsignedIntegerConcept<unsigned long>
{ void __constraints() {} };
template <> struct _UnsignedIntegerConcept<unsigned long long>
{ void __constraints() {} };
//===========================================================================
// Basic Concepts
template <class _Tp>
struct _DefaultConstructibleConcept
{
void __constraints() {
_Tp __a _IsUnused; // require default constructor
}
};
template <class _Tp>
struct _AssignableConcept
{
void __constraints() {
__a = __a; // require assignment operator
__const_constraints(__a);
}
void __const_constraints(const _Tp& __b) {
__a = __b; // const required for argument to assignment
}
_Tp __a;
// possibly should be "Tp* a;" and then dereference "a" in constraint
// functions? present way would require a default ctor, i think...
};
template <class _Tp>
struct _CopyConstructibleConcept
{
void __constraints() {
_Tp __a(__b); // require copy constructor
_Tp* __ptr _IsUnused = &__a; // require address of operator
__const_constraints(__a);
}
void __const_constraints(const _Tp& __a) {
_Tp __c _IsUnused(__a); // require const copy constructor
const _Tp* __ptr _IsUnused = &__a; // require const address of operator
}
_Tp __b;
};
// The SGI STL version of Assignable requires copy constructor and operator=
template <class _Tp>
struct _SGIAssignableConcept
{
void __constraints() {
_Tp __b _IsUnused(__a);
__a = __a; // require assignment operator
__const_constraints(__a);
}
void __const_constraints(const _Tp& __b) {
_Tp __c _IsUnused(__b);
__a = __b; // const required for argument to assignment
}
_Tp __a;
};
template <class _From, class _To>
struct _ConvertibleConcept
{
void __constraints() {
_To __y _IsUnused = __x;
}
_From __x;
};
// The C++ standard requirements for many concepts talk about return
// types that must be "convertible to bool". The problem with this
// requirement is that it leaves the door open for evil proxies that
// define things like operator|| with strange return types. Two
// possible solutions are:
// 1) require the return type to be exactly bool
// 2) stay with convertible to bool, and also
// specify stuff about all the logical operators.
// For now we just test for convertible to bool.
template <class _Tp>
void __aux_require_boolean_expr(const _Tp& __t) {
bool __x _IsUnused = __t;
}
// FIXME
template <class _Tp>
struct _EqualityComparableConcept
{
void __constraints() {
__aux_require_boolean_expr(__a == __b);
}
_Tp __a, __b;
};
template <class _Tp>
struct _LessThanComparableConcept
{
void __constraints() {
__aux_require_boolean_expr(__a < __b);
}
_Tp __a, __b;
};
// This is equivalent to SGI STL's LessThanComparable.
template <class _Tp>
struct _ComparableConcept
{
void __constraints() {
__aux_require_boolean_expr(__a < __b);
__aux_require_boolean_expr(__a > __b);
__aux_require_boolean_expr(__a <= __b);
__aux_require_boolean_expr(__a >= __b);
}
_Tp __a, __b;
};
#define _GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(_OP,_NAME) \
template <class _First, class _Second> \
struct _NAME { \
void __constraints() { (void)__constraints_(); } \
bool __constraints_() { \
return __a _OP __b; \
} \
_First __a; \
_Second __b; \
}
#define _GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(_OP,_NAME) \
template <class _Ret, class _First, class _Second> \
struct _NAME { \
void __constraints() { (void)__constraints_(); } \
_Ret __constraints_() { \
return __a _OP __b; \
} \
_First __a; \
_Second __b; \
}
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(==, _EqualOpConcept);
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(!=, _NotEqualOpConcept);
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(<, _LessThanOpConcept);
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(<=, _LessEqualOpConcept);
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(>, _GreaterThanOpConcept);
_GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT(>=, _GreaterEqualOpConcept);
_GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(+, _PlusOpConcept);
_GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(*, _TimesOpConcept);
_GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(/, _DivideOpConcept);
_GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(-, _SubtractOpConcept);
_GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT(%, _ModOpConcept);
#undef _GLIBCXX_DEFINE_BINARY_PREDICATE_OP_CONSTRAINT
#undef _GLIBCXX_DEFINE_BINARY_OPERATOR_CONSTRAINT
//===========================================================================
// Function Object Concepts
template <class _Func, class _Return>
struct _GeneratorConcept
{
void __constraints() {
const _Return& __r _IsUnused = __f();// require operator() member function
}
_Func __f;
};
template <class _Func>
struct _GeneratorConcept<_Func,void>
{
void __constraints() {
__f(); // require operator() member function
}
_Func __f;
};
template <class _Func, class _Return, class _Arg>
struct _UnaryFunctionConcept
{
void __constraints() {
__r = __f(__arg); // require operator()
}
_Func __f;
_Arg __arg;
_Return __r;
};
template <class _Func, class _Arg>
struct _UnaryFunctionConcept<_Func, void, _Arg> {
void __constraints() {
__f(__arg); // require operator()
}
_Func __f;
_Arg __arg;
};
template <class _Func, class _Return, class _First, class _Second>
struct _BinaryFunctionConcept
{
void __constraints() {
__r = __f(__first, __second); // require operator()
}
_Func __f;
_First __first;
_Second __second;
_Return __r;
};
template <class _Func, class _First, class _Second>
struct _BinaryFunctionConcept<_Func, void, _First, _Second>
{
void __constraints() {
__f(__first, __second); // require operator()
}
_Func __f;
_First __first;
_Second __second;
};
template <class _Func, class _Arg>
struct _UnaryPredicateConcept
{
void __constraints() {
__aux_require_boolean_expr(__f(__arg)); // require op() returning bool
}
_Func __f;
_Arg __arg;
};
template <class _Func, class _First, class _Second>
struct _BinaryPredicateConcept
{
void __constraints() {
__aux_require_boolean_expr(__f(__a, __b)); // require op() returning bool
}
_Func __f;
_First __a;
_Second __b;
};
// use this when functor is used inside a container class like std::set
template <class _Func, class _First, class _Second>
struct _Const_BinaryPredicateConcept {
void __constraints() {
__const_constraints(__f);
}
void __const_constraints(const _Func& __fun) {
__function_requires<_BinaryPredicateConcept<_Func, _First, _Second> >();
// operator() must be a const member function
__aux_require_boolean_expr(__fun(__a, __b));
}
_Func __f;
_First __a;
_Second __b;
};
//===========================================================================
// Iterator Concepts
template <class _Tp>
struct _TrivialIteratorConcept
{
void __constraints() {
// __function_requires< _DefaultConstructibleConcept<_Tp> >();
__function_requires< _AssignableConcept<_Tp> >();
__function_requires< _EqualityComparableConcept<_Tp> >();
// typedef typename std::iterator_traits<_Tp>::value_type _V;
(void)*__i; // require dereference operator
}
_Tp __i;
};
template <class _Tp>
struct _Mutable_TrivialIteratorConcept
{
void __constraints() {
__function_requires< _TrivialIteratorConcept<_Tp> >();
*__i = *__j; // require dereference and assignment
}
_Tp __i, __j;
};
template <class _Tp>
struct _InputIteratorConcept
{
void __constraints() {
__function_requires< _TrivialIteratorConcept<_Tp> >();
// require iterator_traits typedef's
typedef typename std::iterator_traits<_Tp>::difference_type _Diff;
// __function_requires< _SignedIntegerConcept<_Diff> >();
typedef typename std::iterator_traits<_Tp>::reference _Ref;
typedef typename std::iterator_traits<_Tp>::pointer _Pt;
typedef typename std::iterator_traits<_Tp>::iterator_category _Cat;
__function_requires< _ConvertibleConcept<
typename std::iterator_traits<_Tp>::iterator_category,
std::input_iterator_tag> >();
++__i; // require preincrement operator
__i++; // require postincrement operator
}
_Tp __i;
};
template <class _Tp, class _ValueT>
struct _OutputIteratorConcept
{
void __constraints() {
__function_requires< _AssignableConcept<_Tp> >();
++__i; // require preincrement operator
__i++; // require postincrement operator
*__i++ = __t; // require postincrement and assignment
}
_Tp __i;
_ValueT __t;
};
template <class _Tp>
struct _ForwardIteratorConcept
{
void __constraints() {
__function_requires< _InputIteratorConcept<_Tp> >();
__function_requires< _DefaultConstructibleConcept<_Tp> >();
__function_requires< _ConvertibleConcept<
typename std::iterator_traits<_Tp>::iterator_category,
std::forward_iterator_tag> >();
typedef typename std::iterator_traits<_Tp>::reference _Ref;
_Ref __r _IsUnused = *__i;
}
_Tp __i;
};
template <class _Tp>
struct _Mutable_ForwardIteratorConcept
{
void __constraints() {
__function_requires< _ForwardIteratorConcept<_Tp> >();
*__i++ = *__i; // require postincrement and assignment
}
_Tp __i;
};
template <class _Tp>
struct _BidirectionalIteratorConcept
{
void __constraints() {
__function_requires< _ForwardIteratorConcept<_Tp> >();
__function_requires< _ConvertibleConcept<
typename std::iterator_traits<_Tp>::iterator_category,
std::bidirectional_iterator_tag> >();
--__i; // require predecrement operator
__i--; // require postdecrement operator
}
_Tp __i;
};
template <class _Tp>
struct _Mutable_BidirectionalIteratorConcept
{
void __constraints() {
__function_requires< _BidirectionalIteratorConcept<_Tp> >();
__function_requires< _Mutable_ForwardIteratorConcept<_Tp> >();
*__i-- = *__i; // require postdecrement and assignment
}
_Tp __i;
};
template <class _Tp>
struct _RandomAccessIteratorConcept
{
void __constraints() {
__function_requires< _BidirectionalIteratorConcept<_Tp> >();
__function_requires< _ComparableConcept<_Tp> >();
__function_requires< _ConvertibleConcept<
typename std::iterator_traits<_Tp>::iterator_category,
std::random_access_iterator_tag> >();
// ??? We don't use _Ref, are we just checking for "referenceability"?
typedef typename std::iterator_traits<_Tp>::reference _Ref;
__i += __n; // require assignment addition operator
__i = __i + __n; __i = __n + __i; // require addition with difference type
__i -= __n; // require assignment subtraction op
__i = __i - __n; // require subtraction with
// difference type
__n = __i - __j; // require difference operator
(void)__i[__n]; // require element access operator
}
_Tp __a, __b;
_Tp __i, __j;
typename std::iterator_traits<_Tp>::difference_type __n;
};
template <class _Tp>
struct _Mutable_RandomAccessIteratorConcept
{
void __constraints() {
__function_requires< _RandomAccessIteratorConcept<_Tp> >();
__function_requires< _Mutable_BidirectionalIteratorConcept<_Tp> >();
__i[__n] = *__i; // require element access and assignment
}
_Tp __i;
typename std::iterator_traits<_Tp>::difference_type __n;
};
//===========================================================================
// Container Concepts
template <class _Container>
struct _ContainerConcept
{
typedef typename _Container::value_type _Value_type;
typedef typename _Container::difference_type _Difference_type;
typedef typename _Container::size_type _Size_type;
typedef typename _Container::const_reference _Const_reference;
typedef typename _Container::const_pointer _Const_pointer;
typedef typename _Container::const_iterator _Const_iterator;
void __constraints() {
__function_requires< _InputIteratorConcept<_Const_iterator> >();
__function_requires< _AssignableConcept<_Container> >();
const _Container __c;
__i = __c.begin();
__i = __c.end();
__n = __c.size();
__n = __c.max_size();
__b = __c.empty();
}
bool __b;
_Const_iterator __i;
_Size_type __n;
};
template <class _Container>
struct _Mutable_ContainerConcept
{
typedef typename _Container::value_type _Value_type;
typedef typename _Container::reference _Reference;
typedef typename _Container::iterator _Iterator;
typedef typename _Container::pointer _Pointer;
void __constraints() {
__function_requires< _ContainerConcept<_Container> >();
__function_requires< _AssignableConcept<_Value_type> >();
__function_requires< _InputIteratorConcept<_Iterator> >();
__i = __c.begin();
__i = __c.end();
__c.swap(__c2);
}
_Iterator __i;
_Container __c, __c2;
};
template <class _ForwardContainer>
struct _ForwardContainerConcept
{
void __constraints() {
__function_requires< _ContainerConcept<_ForwardContainer> >();
typedef typename _ForwardContainer::const_iterator _Const_iterator;
__function_requires< _ForwardIteratorConcept<_Const_iterator> >();
}
};
template <class _ForwardContainer>
struct _Mutable_ForwardContainerConcept
{
void __constraints() {
__function_requires< _ForwardContainerConcept<_ForwardContainer> >();
__function_requires< _Mutable_ContainerConcept<_ForwardContainer> >();
typedef typename _ForwardContainer::iterator _Iterator;
__function_requires< _Mutable_ForwardIteratorConcept<_Iterator> >();
}
};
template <class _ReversibleContainer>
struct _ReversibleContainerConcept
{
typedef typename _ReversibleContainer::const_iterator _Const_iterator;
typedef typename _ReversibleContainer::const_reverse_iterator
_Const_reverse_iterator;
void __constraints() {
__function_requires< _ForwardContainerConcept<_ReversibleContainer> >();
__function_requires< _BidirectionalIteratorConcept<_Const_iterator> >();
__function_requires<
_BidirectionalIteratorConcept<_Const_reverse_iterator> >();
const _ReversibleContainer __c;
_Const_reverse_iterator __i = __c.rbegin();
__i = __c.rend();
}
};
template <class _ReversibleContainer>
struct _Mutable_ReversibleContainerConcept
{
typedef typename _ReversibleContainer::iterator _Iterator;
typedef typename _ReversibleContainer::reverse_iterator _Reverse_iterator;
void __constraints() {
__function_requires<_ReversibleContainerConcept<_ReversibleContainer> >();
__function_requires<
_Mutable_ForwardContainerConcept<_ReversibleContainer> >();
__function_requires<_Mutable_BidirectionalIteratorConcept<_Iterator> >();
__function_requires<
_Mutable_BidirectionalIteratorConcept<_Reverse_iterator> >();
_Reverse_iterator __i = __c.rbegin();
__i = __c.rend();
}
_ReversibleContainer __c;
};
template <class _RandomAccessContainer>
struct _RandomAccessContainerConcept
{
typedef typename _RandomAccessContainer::size_type _Size_type;
typedef typename _RandomAccessContainer::const_reference _Const_reference;
typedef typename _RandomAccessContainer::const_iterator _Const_iterator;
typedef typename _RandomAccessContainer::const_reverse_iterator
_Const_reverse_iterator;
void __constraints() {
__function_requires<
_ReversibleContainerConcept<_RandomAccessContainer> >();
__function_requires< _RandomAccessIteratorConcept<_Const_iterator> >();
__function_requires<
_RandomAccessIteratorConcept<_Const_reverse_iterator> >();
const _RandomAccessContainer __c;
_Const_reference __r _IsUnused = __c[__n];
}
_Size_type __n;
};
template <class _RandomAccessContainer>
struct _Mutable_RandomAccessContainerConcept
{
typedef typename _RandomAccessContainer::size_type _Size_type;
typedef typename _RandomAccessContainer::reference _Reference;
typedef typename _RandomAccessContainer::iterator _Iterator;
typedef typename _RandomAccessContainer::reverse_iterator _Reverse_iterator;
void __constraints() {
__function_requires<
_RandomAccessContainerConcept<_RandomAccessContainer> >();
__function_requires<
_Mutable_ReversibleContainerConcept<_RandomAccessContainer> >();
__function_requires< _Mutable_RandomAccessIteratorConcept<_Iterator> >();
__function_requires<
_Mutable_RandomAccessIteratorConcept<_Reverse_iterator> >();
_Reference __r _IsUnused = __c[__i];
}
_Size_type __i;
_RandomAccessContainer __c;
};
// A Sequence is inherently mutable
template <class _Sequence>
struct _SequenceConcept
{
typedef typename _Sequence::reference _Reference;
typedef typename _Sequence::const_reference _Const_reference;
void __constraints() {
// Matt Austern's book puts DefaultConstructible here, the C++
// standard places it in Container
// function_requires< DefaultConstructible<Sequence> >();
__function_requires< _Mutable_ForwardContainerConcept<_Sequence> >();
__function_requires< _DefaultConstructibleConcept<_Sequence> >();
_Sequence
__c _IsUnused(__n, __t),
__c2 _IsUnused(__first, __last);
__c.insert(__p, __t);
__c.insert(__p, __n, __t);
__c.insert(__p, __first, __last);
__c.erase(__p);
__c.erase(__p, __q);
_Reference __r _IsUnused = __c.front();
__const_constraints(__c);
}
void __const_constraints(const _Sequence& __c) {
_Const_reference __r _IsUnused = __c.front();
}
typename _Sequence::value_type __t;
typename _Sequence::size_type __n;
typename _Sequence::value_type *__first, *__last;
typename _Sequence::iterator __p, __q;
};
template <class _FrontInsertionSequence>
struct _FrontInsertionSequenceConcept
{
void __constraints() {
__function_requires< _SequenceConcept<_FrontInsertionSequence> >();
__c.push_front(__t);
__c.pop_front();
}
_FrontInsertionSequence __c;
typename _FrontInsertionSequence::value_type __t;
};
template <class _BackInsertionSequence>
struct _BackInsertionSequenceConcept
{
typedef typename _BackInsertionSequence::reference _Reference;
typedef typename _BackInsertionSequence::const_reference _Const_reference;
void __constraints() {
__function_requires< _SequenceConcept<_BackInsertionSequence> >();
__c.push_back(__t);
__c.pop_back();
_Reference __r _IsUnused = __c.back();
}
void __const_constraints(const _BackInsertionSequence& __c) {
_Const_reference __r _IsUnused = __c.back();
};
_BackInsertionSequence __c;
typename _BackInsertionSequence::value_type __t;
};
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#undef _IsUnused
#endif // _GLIBCXX_BOOST_CONCEPT_CHECK