| // Copyright 2005 The Trustees of Indiana University. | |
| // 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) | |
| // Authors: Douglas Gregor | |
| // Andrew Lumsdaine | |
| #ifndef BOOST_PARALLEL_BASIC_REDUCE_HPP | |
| #define BOOST_PARALLEL_BASIC_REDUCE_HPP | |
| #ifndef BOOST_GRAPH_USE_MPI | |
| #error "Parallel BGL files should not be included unless <boost/graph/use_mpi.hpp> has been included" | |
| #endif | |
| namespace boost { namespace parallel { | |
| /** Reduction operation used to reconcile differences between local | |
| * and remote values for a particular key in a property map. The | |
| * type @c T is typically the @c value_type of the property | |
| * map. This basic reduction returns a default-constructed @c T as | |
| * the default value and always resolves to the remote value. | |
| */ | |
| template<typename T> | |
| struct basic_reduce | |
| { | |
| BOOST_STATIC_CONSTANT(bool, non_default_resolver = false); | |
| /// Returns a default-constructed T object | |
| template<typename Key> | |
| T operator()(const Key&) const { return T(); } | |
| /// Returns the remote value | |
| template<typename Key> | |
| const T& operator()(const Key&, const T&, const T& remote) const | |
| { return remote; } | |
| }; | |
| } } // end namespace boost::parallel | |
| #endif // BOOST_PARALLEL_BASIC_REDUCE_HPP |