| 1 | // Boost.Range library |
| 2 | // |
| 3 | // Copyright Thorsten Ottosen, Neil Groves 2006 - 2008. Use, modification and |
| 4 | // distribution is subject to the Boost Software License, Version |
| 5 | // 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| 6 | // http://www.boost.org/LICENSE_1_0.txt) |
| 7 | // |
| 8 | // For more information, see http://www.boost.org/libs/range/ |
| 9 | // |
| 10 | |
| 11 | #ifndef BOOST_RANGE_ADAPTOR_SLICED_HPP |
| 12 | #define BOOST_RANGE_ADAPTOR_SLICED_HPP |
| 13 | |
| 14 | #include <boost/range/adaptor/argument_fwd.hpp> |
| 15 | #include <boost/range/size_type.hpp> |
| 16 | #include <boost/range/iterator_range.hpp> |
| 17 | #include <boost/range/concepts.hpp> |
| 18 | #include <boost/next_prior.hpp> |
| 19 | |
| 20 | namespace boost |
| 21 | { |
| 22 | namespace adaptors |
| 23 | { |
| 24 | struct sliced |
| 25 | { |
| 26 | sliced(std::size_t t_, std::size_t u_) |
| 27 | : t(t_), u(u_) {} |
| 28 | std::size_t t; |
| 29 | std::size_t u; |
| 30 | }; |
| 31 | |
| 32 | template< class RandomAccessRange > |
| 33 | class sliced_range : public boost::iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<RandomAccessRange>::type > |
| 34 | { |
| 35 | typedef boost::iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<RandomAccessRange>::type > base_t; |
| 36 | public: |
| 37 | template<typename Rng, typename T, typename U> |
| 38 | sliced_range(Rng& rng, T t, U u) |
| 39 | : base_t(boost::next(boost::begin(rng), t), |
| 40 | boost::next(boost::begin(rng), u)) |
| 41 | { |
| 42 | } |
| 43 | }; |
| 44 | |
| 45 | template< class RandomAccessRange > |
| 46 | inline sliced_range<RandomAccessRange> |
| 47 | slice( RandomAccessRange& rng, std::size_t t, std::size_t u ) |
| 48 | { |
| 49 | BOOST_RANGE_CONCEPT_ASSERT(( |
| 50 | RandomAccessRangeConcept<RandomAccessRange>)); |
| 51 | |
| 52 | BOOST_ASSERT( t <= u && "error in slice indices" ); |
| 53 | BOOST_ASSERT( static_cast<std::size_t>(boost::size(rng)) >= u && |
| 54 | "second slice index out of bounds" ); |
| 55 | |
| 56 | return sliced_range<RandomAccessRange>(rng, t, u); |
| 57 | } |
| 58 | |
| 59 | template< class RandomAccessRange > |
| 60 | inline iterator_range< BOOST_DEDUCED_TYPENAME range_iterator<const RandomAccessRange>::type > |
| 61 | slice( const RandomAccessRange& rng, std::size_t t, std::size_t u ) |
| 62 | { |
| 63 | BOOST_RANGE_CONCEPT_ASSERT(( |
| 64 | RandomAccessRangeConcept<const RandomAccessRange>)); |
| 65 | |
| 66 | BOOST_ASSERT( t <= u && "error in slice indices" ); |
| 67 | BOOST_ASSERT( static_cast<std::size_t>(boost::size(rng)) >= u && |
| 68 | "second slice index out of bounds" ); |
| 69 | |
| 70 | return sliced_range<const RandomAccessRange>(rng, t, u); |
| 71 | } |
| 72 | |
| 73 | template< class RandomAccessRange > |
| 74 | inline sliced_range<RandomAccessRange> |
| 75 | operator|( RandomAccessRange& r, const sliced& f ) |
| 76 | { |
| 77 | BOOST_RANGE_CONCEPT_ASSERT(( |
| 78 | RandomAccessRangeConcept<RandomAccessRange>)); |
| 79 | |
| 80 | return sliced_range<RandomAccessRange>( r, f.t, f.u ); |
| 81 | } |
| 82 | |
| 83 | template< class RandomAccessRange > |
| 84 | inline sliced_range<const RandomAccessRange> |
| 85 | operator|( const RandomAccessRange& r, const sliced& f ) |
| 86 | { |
| 87 | BOOST_RANGE_CONCEPT_ASSERT(( |
| 88 | RandomAccessRangeConcept<const RandomAccessRange>)); |
| 89 | |
| 90 | return sliced_range<const RandomAccessRange>( r, f.t, f.u ); |
| 91 | } |
| 92 | |
| 93 | } // namespace adaptors |
| 94 | using adaptors::sliced_range; |
| 95 | } // namespace boost |
| 96 | |
| 97 | #endif |
| 98 | |