1 // (C) Copyright Gennadiy Rozental 2004-2008. 2 // Distributed under the Boost Software License, Version 1.0. 3 // (See accompanying file LICENSE_1_0.txt or copy at 4 // http://www.boost.org/LICENSE_1_0.txt) 5 6 // See http://www.boost.org/libs/test for the library home page. 7 // 8 // File : $RCSfile$ 9 // 10 // Version : $Revision: 49312 $ 11 // 12 // Description : Input iterator facade 13 // *************************************************************************** 14 15 #ifndef BOOST_INPUT_ITERATOR_FACADE_HPP_071894GER 16 #define BOOST_INPUT_ITERATOR_FACADE_HPP_071894GER 17 18 // Boost 19 #include <boost/iterator/iterator_facade.hpp> 20 21 #include <boost/test/detail/suppress_warnings.hpp> 22 23 //____________________________________________________________________________// 24 25 namespace boost { 26 27 namespace unit_test { 28 29 // ************************************************************************** // 30 // ************** input_iterator_core_access ************** // 31 // ************************************************************************** // 32 33 class input_iterator_core_access 34 { 35 #if defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS) || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551)) 36 public: 37 #else 38 template <class I, class V, class R, class TC> friend class input_iterator_facade; 39 #endif 40 41 template <class Facade> get(Facade & f)42 static bool get( Facade& f ) 43 { 44 return f.get(); 45 } 46 47 private: 48 // objects of this class are useless 49 input_iterator_core_access(); //undefined 50 }; 51 52 // ************************************************************************** // 53 // ************** input_iterator_facade ************** // 54 // ************************************************************************** // 55 56 template<typename Derived, 57 typename ValueType, 58 typename Reference = ValueType const&, 59 typename Traversal = single_pass_traversal_tag> 60 class input_iterator_facade : public iterator_facade<Derived,ValueType,Traversal,Reference> 61 { 62 public: 63 // Constructor input_iterator_facade()64 input_iterator_facade() : m_valid( false ), m_value() {} 65 66 protected: // provide access to the Derived init()67 void init() 68 { 69 m_valid = true; 70 increment(); 71 } 72 73 // Data members 74 mutable bool m_valid; 75 ValueType m_value; 76 77 private: 78 friend class boost::iterator_core_access; 79 80 // iterator facade interface implementation increment()81 void increment() 82 { 83 // we make post-end incrementation indefinetly safe 84 if( m_valid ) 85 m_valid = input_iterator_core_access::get( *static_cast<Derived*>(this) ); 86 } dereference() const87 Reference dereference() const 88 { 89 return m_value; 90 } 91 92 // iterator facade interface implementation equal(input_iterator_facade const & rhs) const93 bool equal( input_iterator_facade const& rhs ) const 94 { 95 // two invalid iterator equals, inequal otherwise 96 return !m_valid && !rhs.m_valid; 97 } 98 }; 99 100 } // namespace unit_test 101 102 } // namespace boost 103 104 //____________________________________________________________________________// 105 106 #include <boost/test/detail/enable_warnings.hpp> 107 108 #endif // BOOST_INPUT_ITERATOR_FACADE_HPP_071894GER 109 110