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Diffstat (limited to 'boost/geometry/iterators/concatenate_iterator.hpp')
| -rw-r--r-- | boost/geometry/iterators/concatenate_iterator.hpp | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/boost/geometry/iterators/concatenate_iterator.hpp b/boost/geometry/iterators/concatenate_iterator.hpp new file mode 100644 index 0000000000..20112b4c4c --- /dev/null +++ b/boost/geometry/iterators/concatenate_iterator.hpp @@ -0,0 +1,184 @@ +// Boost.Geometry (aka GGL, Generic Geometry Library) + +// Copyright (c) 2014, Oracle and/or its affiliates. + +// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle + +// Licensed under the Boost Software License version 1.0. +// http://www.boost.org/users/license.html + +#ifndef BOOST_GEOMETRY_ITERATORS_CONCATENATE_ITERATOR_HPP +#define BOOST_GEOMETRY_ITERATORS_CONCATENATE_ITERATOR_HPP + +#include <boost/assert.hpp> +#include <boost/mpl/assert.hpp> +#include <boost/type_traits/is_convertible.hpp> +#include <boost/iterator.hpp> +#include <boost/iterator/iterator_facade.hpp> +#include <boost/iterator/iterator_categories.hpp> + + +namespace boost { namespace geometry +{ + + + +template +< + typename Iterator1, + typename Iterator2, + typename Value, + typename Reference = Value& +> +class concatenate_iterator + : public boost::iterator_facade + < + concatenate_iterator<Iterator1, Iterator2, Value, Reference>, + Value, + boost::bidirectional_traversal_tag, + Reference + > +{ +private: + Iterator1 m_it1, m_end1; + Iterator2 m_begin2, m_it2; + +public: + typedef Iterator1 first_iterator_type; + typedef Iterator2 second_iterator_type; + + // default constructor + concatenate_iterator() {} + + // for begin + concatenate_iterator(Iterator1 it1, Iterator1 end1, + Iterator2 begin2, Iterator2 it2) + : m_it1(it1), m_end1(end1), m_begin2(begin2), m_it2(it2) + {} + + // for end + concatenate_iterator(Iterator1 end1, Iterator2 begin2, Iterator2 end2) + : m_it1(end1), m_end1(end1), m_begin2(begin2), m_it2(end2) + {} + + template + < + typename OtherIt1, + typename OtherIt2, + typename OtherValue, + typename OtherReference + > + concatenate_iterator(concatenate_iterator + < + OtherIt1, + OtherIt2, + OtherValue, + OtherReference + > const& other) + : m_it1(other.m_it1) + , m_end1(other.m_end1) + , m_begin2(other.m_begin2) + , m_it2(other.m_it2) + { + static const bool are_conv + = boost::is_convertible<OtherIt1, Iterator1>::value + && boost::is_convertible<OtherIt2, Iterator2>::value; + + BOOST_MPL_ASSERT_MSG((are_conv), + NOT_CONVERTIBLE, + (types<OtherIt1, OtherIt2>)); + } + + template + < + typename OtherIt1, + typename OtherIt2, + typename OtherValue, + typename OtherReference + > + concatenate_iterator operator=(concatenate_iterator + < + OtherIt1, + OtherIt2, + OtherValue, + OtherReference + > const& other) + { + static const bool are_conv + = boost::is_convertible<OtherIt1, Iterator1>::value + && boost::is_convertible<OtherIt2, Iterator2>::value; + + BOOST_MPL_ASSERT_MSG((are_conv), + NOT_CONVERTIBLE, + (types<OtherIt1, OtherIt2>)); + + m_it1 = other.m_it1; + m_end1 = other.m_end1; + m_begin2 = other.m_begin2; + m_it2 = other.m_it2; + return *this; + } + +private: + friend class boost::iterator_core_access; + + template <typename It1, typename It2, typename V, typename R> + friend class concatenate_iterator; + + inline Reference dereference() const + { + if ( m_it1 == m_end1 ) + { + return *m_it2; + } + return *m_it1; + } + + template + < + typename OtherIt1, + typename OtherIt2, + typename OtherValue, + typename OtherReference + > + inline bool equal(concatenate_iterator + < + OtherIt1, + OtherIt2, + OtherValue, + OtherReference + > const& other) const + { + return m_it1 == other.m_it1 && m_it2 == other.m_it2; + } + + inline void increment() + { + if ( m_it1 == m_end1 ) + { + ++m_it2; + } + else + { + ++m_it1; + } + } + + inline void decrement() + { + if ( m_it2 == m_begin2 ) + { + --m_it1; + } + else + { + --m_it2; + } + } +}; + + + +}} // namespace boost::geometry + +#endif // BOOST_GEOMETRY_ITERATORS_CONCATENATE_ITERATOR_HPP |