mapreduce.h

Go to the documentation of this file.

#ifndef GRPPI_MAPREDUCE_H 
#define GRPPI_MAPREDUCE_H

#include <utility>

#include "common/execution_traits.h"
#include "common/iterator_traits.h"

namespace grppi {

template <typename Execution, typename ...InputIterators,
    typename Identity, typename Transformer, typename Combiner,
    requires_iterators<InputIterators...> = 0>
auto map_reduce(const Execution & ex,
                std::tuple<InputIterators...> firsts, std::size_t size,
                Identity && identity,
                Transformer &&  transform_op, Combiner && combine_op)
{
  static_assert(supports_map_reduce<Execution>(),
                "map/reduce not supported on execution type");
  return ex.map_reduce(firsts, size,
                       std::forward<Identity>(identity),
                       std::forward<Transformer>(transform_op),
                       std::forward<Combiner>(combine_op));
}

template <typename Execution, typename ...InputIterators, typename InputIt,
          typename Identity, typename Transformer, typename Combiner,
          requires_iterators<InputIterators...> = 0,
          requires_iterator<InputIt> = 0>
auto map_reduce(const Execution & ex,
                std::tuple<InputIterators...> firsts, InputIt last,
                Identity && identity,
                Transformer &&  transform_op, Combiner && combine_op)
{
  static_assert(supports_map_reduce<Execution>(),
                "map/reduce not supported on execution type");
  return ex.map_reduce(firsts,
                       std::distance(std::get<0>(firsts),last),
                       std::forward<Identity>(identity),
                       std::forward<Transformer>(transform_op),
                       std::forward<Combiner>(combine_op));
}

template <typename Execution, typename InputIterator, typename Identity, 
          typename Transformer, typename Combiner,
          requires_iterator<InputIterator> = 0>
auto map_reduce(const Execution & ex, 
                InputIterator first, InputIterator last, 
                Identity && identity, 
                Transformer &&  transform_op, Combiner && combine_op)
{
  static_assert(supports_map_reduce<Execution>(),
    "map/reduce not supported on execution type");
  return ex.map_reduce(make_tuple(first), std::distance(first,last), 
      std::forward<Identity>(identity),
      std::forward<Transformer>(transform_op), 
      std::forward<Combiner>(combine_op));
}

template <typename Execution, typename InputIterator, typename Identity, 
          typename Transformer, typename Combiner,
          typename ... OtherInputIterators,
          requires_iterator<InputIterator> = 0>
[[deprecated("This version of the interface is deprecated.\n"
             "If you want to use multiple inputs, use a tuple instead.")]]
auto map_reduce(const Execution & ex,
                InputIterator first, InputIterator last, 
                Identity && identity, 
                Transformer &&  transform_op, Combiner && combine_op,
                OtherInputIterators ... other_firsts)
{
  static_assert(supports_map_reduce<Execution>(),
    "map/reduce not supported on execution type");
  return ex.map_reduce(make_tuple(first, other_firsts...), 
      std::distance(first,last), 
      std::forward<Identity>(identity),
      std::forward<Transformer>(transform_op), 
      std::forward<Combiner>(combine_op));
}

}

#endif