boost/range/algorithm/transform.hpp

   1 //  Copyright Neil Groves 2009. Use, modification and
   2 //  distribution is subject to the Boost Software License, Version
   3 //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
   4 //  http://www.boost.org/LICENSE_1_0.txt)
   5 //
   6 //
   7 // For more information, see http://www.boost.org/libs/range/
   8 //
   9 #ifndef BOOST_RANGE_ALGORITHM_TRANSFORM_HPP_INCLUDED
  10 #define BOOST_RANGE_ALGORITHM_TRANSFORM_HPP_INCLUDED
  11
  12 #include <boost/assert.hpp>
  13 #include <boost/concept_check.hpp>
  14 #include <boost/range/begin.hpp>
  15 #include <boost/range/end.hpp>
  16 #include <boost/range/concepts.hpp>
  17 #include <algorithm>
  18
  19 namespace boost
  20 {
  21     namespace range
  22     {
  23
  24         /// \brief template function transform
  25         ///
  26         /// range-based version of the transform std algorithm
  27         ///
  28         /// \pre SinglePassRange1 is a model of the SinglePassRangeConcept
  29         /// \pre SinglePassRange2 is a model of the SinglePassRangeConcept
  30         /// \pre OutputIterator is a model of the OutputIteratorConcept
  31         /// \pre UnaryOperation is a model of the UnaryFunctionConcept
  32         /// \pre BinaryOperation is a model of the BinaryFunctionConcept
  33         template< class SinglePassRange1,
  34                   class OutputIterator,
  35                   class UnaryOperation >
  36         inline OutputIterator
  37         transform(const SinglePassRange1& rng,
  38                   OutputIterator          out,
  39                   UnaryOperation          fun)
  40         {
  41             BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange1> ));
  42             return std::transform(boost::begin(rng),boost::end(rng),out,fun);
  43         }
  44
  45     } // namespace range
  46
  47     namespace range_detail
  48     {
  49         template< class SinglePassTraversalReadableIterator1,
  50                   class SinglePassTraversalReadableIterator2,
  51                   class OutputIterator,
  52                   class BinaryFunction >
  53         inline OutputIterator
  54         transform_impl(SinglePassTraversalReadableIterator1 first1,
  55                        SinglePassTraversalReadableIterator1 last1,
  56                        SinglePassTraversalReadableIterator2 first2,
  57                        SinglePassTraversalReadableIterator2 last2,
  58                        OutputIterator                       out,
  59                        BinaryFunction                       fn)
  60         {
  61             for (; first1 != last1 && first2 != last2; ++first1, ++first2)
  62             {
  63                 *out = fn(*first1, *first2);
  64                 ++out;
  65             }
  66             return out;
  67         }
  68     }
  69
  70     namespace range
  71     {
  72
  73         /// \overload
  74         template< class SinglePassRange1,
  75                   class SinglePassRange2,
  76                   class OutputIterator,
  77                   class BinaryOperation >
  78         inline OutputIterator
  79         transform(const SinglePassRange1& rng1,
  80                   const SinglePassRange2& rng2,
  81                   OutputIterator          out,
  82                   BinaryOperation         fun)
  83         {
  84             BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange1> ));
  85             BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange2> ));
  86             return boost::range_detail::transform_impl(
  87                         boost::begin(rng1), boost::end(rng1),
  88                         boost::begin(rng2), boost::end(rng2),
  89                         out, fun);
  90         }
  91
  92     } // namespace range
  93     using range::transform;
  94 } // namespace boost
  95
  96 #endif // include guard