| // Boost.Range library |
| // |
| // Copyright Neil Groves 2007. Use, modification and |
| // distribution is subject to the Boost Software License, Version |
| // 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| // |
| // For more information, see http://www.boost.org/libs/range/ |
| // |
| |
| #ifndef BOOST_RANGE_ADAPTOR_REPLACED_IMPL_HPP_INCLUDED |
| #define BOOST_RANGE_ADAPTOR_REPLACED_IMPL_HPP_INCLUDED |
| |
| #include <boost/config.hpp> |
| #include <boost/range/adaptor/argument_fwd.hpp> |
| #include <boost/range/iterator_range.hpp> |
| #include <boost/range/begin.hpp> |
| #include <boost/range/end.hpp> |
| #include <boost/range/value_type.hpp> |
| #include <boost/range/concepts.hpp> |
| #include <boost/iterator/iterator_adaptor.hpp> |
| #include <boost/iterator/transform_iterator.hpp> |
| #include <boost/optional/optional.hpp> |
| |
| namespace boost |
| { |
| namespace range_detail |
| { |
| template< class Value > |
| class replace_value |
| { |
| public: |
| typedef const Value& result_type; |
| typedef const Value& first_argument_type; |
| |
| // Rationale: |
| // The default constructor is required to allow the transform |
| // iterator to properly model the iterator concept. |
| replace_value() |
| { |
| } |
| |
| replace_value(const Value& from, const Value& to) |
| : m_impl(data(from, to)) |
| { |
| } |
| |
| const Value& operator()(const Value& x) const |
| { |
| return (x == m_impl->m_from) ? m_impl->m_to : x; |
| } |
| |
| private: |
| struct data |
| { |
| data(const Value& from, const Value& to) |
| : m_from(from) |
| , m_to(to) |
| { |
| } |
| |
| Value m_from; |
| Value m_to; |
| }; |
| boost::optional<data> m_impl; |
| }; |
| |
| template< class R > |
| class replaced_range : |
| public boost::iterator_range< |
| boost::transform_iterator< |
| replace_value< BOOST_DEDUCED_TYPENAME range_value<R>::type >, |
| BOOST_DEDUCED_TYPENAME range_iterator<R>::type > > |
| { |
| private: |
| typedef replace_value< BOOST_DEDUCED_TYPENAME range_value<R>::type > Fn; |
| |
| typedef boost::iterator_range< |
| boost::transform_iterator< |
| replace_value< BOOST_DEDUCED_TYPENAME range_value<R>::type >, |
| BOOST_DEDUCED_TYPENAME range_iterator<R>::type > > base_t; |
| |
| public: |
| typedef BOOST_DEDUCED_TYPENAME range_value<R>::type value_type; |
| |
| replaced_range( R& r, value_type from, value_type to ) |
| : base_t( make_transform_iterator( boost::begin(r), Fn(from, to) ), |
| make_transform_iterator( boost::end(r), Fn(from, to) ) ) |
| { } |
| }; |
| |
| template< class T > |
| class replace_holder : public holder2<T> |
| { |
| public: |
| replace_holder( const T& from, const T& to ) |
| : holder2<T>(from, to) |
| { } |
| private: |
| // not assignable |
| void operator=(const replace_holder&); |
| }; |
| |
| template< class SinglePassRange > |
| inline replaced_range<SinglePassRange> |
| operator|( |
| SinglePassRange& r, |
| const replace_holder< |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type>& f ) |
| { |
| BOOST_RANGE_CONCEPT_ASSERT(( |
| SinglePassRangeConcept<SinglePassRange>)); |
| |
| return replaced_range<SinglePassRange>(r, f.val1, f.val2); |
| } |
| |
| template< class SinglePassRange > |
| inline replaced_range<const SinglePassRange> |
| operator|( |
| const SinglePassRange& r, |
| const replace_holder< |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type>& f) |
| { |
| BOOST_RANGE_CONCEPT_ASSERT(( |
| SinglePassRangeConcept<const SinglePassRange>)); |
| |
| return replaced_range<const SinglePassRange>(r, f.val1, f.val2); |
| } |
| } // 'range_detail' |
| |
| using range_detail::replaced_range; |
| |
| namespace adaptors |
| { |
| namespace |
| { |
| const range_detail::forwarder2<range_detail::replace_holder> |
| replaced = |
| range_detail::forwarder2<range_detail::replace_holder>(); |
| } |
| |
| template<class SinglePassRange> |
| inline replaced_range<SinglePassRange> |
| replace(SinglePassRange& rng, |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type from, |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type to) |
| { |
| BOOST_RANGE_CONCEPT_ASSERT(( |
| SinglePassRangeConcept<SinglePassRange>)); |
| |
| return replaced_range<SinglePassRange>(rng, from, to); |
| } |
| |
| template<class SinglePassRange> |
| inline replaced_range<const SinglePassRange> |
| replace(const SinglePassRange& rng, |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type from, |
| BOOST_DEDUCED_TYPENAME range_value<SinglePassRange>::type to) |
| { |
| BOOST_RANGE_CONCEPT_ASSERT(( |
| SinglePassRangeConcept<const SinglePassRange>)); |
| |
| return replaced_range<const SinglePassRange>(rng, from ,to); |
| } |
| |
| } // 'adaptors' |
| } // 'boost' |
| |
| #endif // include guard |