v3/algorithm/adjacent_remove_if.hpp

0001 /// \file
0002 // Range v3 library
0003 //
0004 //  Copyright Eric Niebler
0005 //  Copyright Christopher Di Bella
0006 //
0007 //  Use, modification and distribution is subject to the
0008 //  Boost Software License, Version 1.0. (See accompanying
0009 //  file LICENSE_1_0.txt or copy at
0010 //  http://www.boost.org/LICENSE_1_0.txt)
0011 //
0012 // Project home: https://github.com/ericniebler/range-v3
0013 //
0014 #ifndef RANGES_V3_ALGORITHM_ADJACENT_REMOVE_IF_HPP
0015 #define RANGES_V3_ALGORITHM_ADJACENT_REMOVE_IF_HPP
0016
0017 #include <functional>
0018 #include <utility>
0019
0020 #include <range/v3/range_fwd.hpp>
0021
0022 #include <range/v3/algorithm/adjacent_find.hpp>
0023 #include <range/v3/algorithm/move.hpp>
0024 #include <range/v3/functional/identity.hpp>
0025 #include <range/v3/functional/invoke.hpp>
0026 #include <range/v3/iterator/concepts.hpp>
0027 #include <range/v3/iterator/traits.hpp>
0028 #include <range/v3/range/access.hpp>
0029 #include <range/v3/range/concepts.hpp>
0030 #include <range/v3/range/traits.hpp>
0031 #include <range/v3/utility/move.hpp>
0032 #include <range/v3/utility/static_const.hpp>
0033
0034 #include <range/v3/detail/prologue.hpp>
0035
0036 namespace ranges
0037 {
0038     /// \addtogroup group-algorithms
0039     /// @{
0040     RANGES_FUNC_BEGIN(adjacent_remove_if)
0041         /// \brief function \c adjacent_remove_if
0042         ///
0043         /// range-based version of the \c adjacent_remove_if algorithm
0044         ///
0045         /// \pre `Rng` is a model of the `forward_range` concept.
0046         /// \pre `Pred` is a model of the `BinaryPredicate` concept.
0047         template(typename I, typename S, typename Pred, typename Proj = identity)(
0048             requires permutable<I> AND sentinel_for<S, I> AND
0049                 indirect_relation<Pred, projected<I, Proj>>)
0050         constexpr I RANGES_FUNC(adjacent_remove_if)(I first, S last, Pred pred = {}, Proj proj = {})
0051         {
0052             first = adjacent_find(std::move(first), last, ranges::ref(pred), ranges::ref(proj));
0053             if(first == last)
0054                 return first;
0055
0056             auto i = first;
0057             for(auto j = ++i; ++j != last; ++i)
0058             {
0059                 if(!invoke(pred, invoke(proj, *i), invoke(proj, *j)))
0060                 {
0061                     *first = iter_move(i);
0062                     ++first;
0063                 }
0064             }
0065
0066             *first = iter_move(i);
0067             ++first;
0068             return first;
0069         }
0070
0071         /// \overload
0072         template(typename Rng, typename Pred, typename Proj = identity)(
0073             requires forward_range<Rng> AND
0074             indirect_relation<Pred, projected<iterator_t<Rng>, Proj>> AND
0075             permutable<iterator_t<Rng>>)
0076         constexpr borrowed_iterator_t<Rng>
0077         RANGES_FUNC(adjacent_remove_if)(Rng && rng, Pred pred, Proj proj = {}) //
0078         {
0079             return (*this)(begin(rng), end(rng), std::move(pred), std::move(proj));
0080         }
0081     RANGES_FUNC_END(adjacent_remove_if)
0082
0083     namespace cpp20
0084     {
0085         using ranges::adjacent_remove_if;
0086     }
0087     /// @}
0088 } // namespace ranges
0089
0090 #include <range/v3/detail/epilogue.hpp>
0091
0092 #endif // RANGES_V3_ALGORITHM_ADJACENT_REMOVE_IF_HPP