1 // (C) Copyright Jens Maurer 2001. 2 // Distributed under the Boost Software License, Version 1.0. (See 3 // accompanying file LICENSE_1_0.txt or copy at 4 // http://www.boost.org/LICENSE_1_0.txt) 5 // 6 // Revision History: 7 8 // 15 Nov 2001 Jens Maurer 9 // created. 10 11 // See http://www.boost.org/libs/utility/iterator_adaptors.htm for documentation. 12 13 #ifndef BOOST_ITERATOR_ADAPTOR_GENERATOR_ITERATOR_HPP 14 #define BOOST_ITERATOR_ADAPTOR_GENERATOR_ITERATOR_HPP 15 16 #include <boost/iterator/iterator_facade.hpp> 17 #include <boost/ref.hpp> 18 19 namespace boost { 20 namespace iterators { 21 22 template<class Generator> 23 class generator_iterator 24 : public iterator_facade< 25 generator_iterator<Generator> 26 , typename Generator::result_type 27 , single_pass_traversal_tag 28 , typename Generator::result_type const& 29 > 30 { 31 typedef iterator_facade< 32 generator_iterator<Generator> 33 , typename Generator::result_type 34 , single_pass_traversal_tag 35 , typename Generator::result_type const& 36 > super_t; 37 38 public: 39 generator_iterator() {} 40 generator_iterator(Generator* g) : m_g(g), m_value((*m_g)()) {} 41 42 void increment() 43 { 44 m_value = (*m_g)(); 45 } 46 47 const typename Generator::result_type& 48 dereference() const 49 { 50 return m_value; 51 } 52 53 bool equal(generator_iterator const& y) const 54 { 55 return this->m_g == y.m_g && this->m_value == y.m_value; 56 } 57 58 private: 59 Generator* m_g; 60 typename Generator::result_type m_value; 61 }; 62 63 template<class Generator> 64 struct generator_iterator_generator 65 { 66 typedef generator_iterator<Generator> type; 67 }; 68 69 template <class Generator> 70 inline generator_iterator<Generator> 71 make_generator_iterator(Generator & gen) 72 { 73 typedef generator_iterator<Generator> result_t; 74 return result_t(&gen); 75 } 76 77 } // namespace iterators 78 79 using iterators::generator_iterator; 80 using iterators::generator_iterator_generator; 81 using iterators::make_generator_iterator; 82 83 } // namespace boost 84 85 #endif // BOOST_ITERATOR_ADAPTOR_GENERATOR_ITERATOR_HPP 86