1 | // (C) Copyright Toon Knapen 2001. |
2 | // (C) Copyright David Abrahams 2003. |
3 | // (C) Copyright Roland Richter 2003. |
4 | // Distributed under the Boost Software License, Version 1.0. (See |
5 | // accompanying file LICENSE_1_0.txt or copy at |
6 | // http://www.boost.org/LICENSE_1_0.txt) |
7 | |
8 | #ifndef BOOST_PERMUTATION_ITERATOR_HPP |
9 | #define BOOST_PERMUTATION_ITERATOR_HPP |
10 | |
11 | #include <iterator> |
12 | |
13 | #include <boost/iterator/iterator_adaptor.hpp> |
14 | |
15 | |
16 | namespace boost { |
17 | namespace iterators { |
18 | |
19 | template< class ElementIterator |
20 | , class IndexIterator> |
21 | class permutation_iterator |
22 | : public iterator_adaptor< |
23 | permutation_iterator<ElementIterator, IndexIterator> |
24 | , IndexIterator, typename std::iterator_traits<ElementIterator>::value_type |
25 | , use_default, typename std::iterator_traits<ElementIterator>::reference> |
26 | { |
27 | typedef iterator_adaptor< |
28 | permutation_iterator<ElementIterator, IndexIterator> |
29 | , IndexIterator, typename std::iterator_traits<ElementIterator>::value_type |
30 | , use_default, typename std::iterator_traits<ElementIterator>::reference> super_t; |
31 | |
32 | friend class iterator_core_access; |
33 | |
34 | public: |
35 | permutation_iterator() : m_elt_iter() {} |
36 | |
37 | explicit permutation_iterator(ElementIterator x, IndexIterator y) |
38 | : super_t(y), m_elt_iter(x) {} |
39 | |
40 | template<class OtherElementIterator, class OtherIndexIterator> |
41 | permutation_iterator( |
42 | permutation_iterator<OtherElementIterator, OtherIndexIterator> const& r |
43 | , typename enable_if_convertible<OtherElementIterator, ElementIterator>::type* = 0 |
44 | , typename enable_if_convertible<OtherIndexIterator, IndexIterator>::type* = 0 |
45 | ) |
46 | : super_t(r.base()), m_elt_iter(r.m_elt_iter) |
47 | {} |
48 | |
49 | private: |
50 | typename super_t::reference dereference() const |
51 | { return *(m_elt_iter + *this->base()); } |
52 | |
53 | #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS |
54 | template <class,class> friend class permutation_iterator; |
55 | #else |
56 | public: |
57 | #endif |
58 | ElementIterator m_elt_iter; |
59 | }; |
60 | |
61 | |
62 | template <class ElementIterator, class IndexIterator> |
63 | inline permutation_iterator<ElementIterator, IndexIterator> |
64 | make_permutation_iterator( ElementIterator e, IndexIterator i ) |
65 | { |
66 | return permutation_iterator<ElementIterator, IndexIterator>( e, i ); |
67 | } |
68 | |
69 | } // namespace iterators |
70 | |
71 | using iterators::permutation_iterator; |
72 | using iterators::make_permutation_iterator; |
73 | |
74 | } // namespace boost |
75 | |
76 | #endif |
77 | |