.. _program_listing_file__tmp_ws_src_warehouse_ros_include_warehouse_ros_query_results.h:

Program Listing for File query_results.h
========================================

|exhale_lsh| :ref:`Return to documentation for file <file__tmp_ws_src_warehouse_ros_include_warehouse_ros_query_results.h>` (``/tmp/ws/src/warehouse_ros/include/warehouse_ros/query_results.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright 2008 Willow Garage, Inc.
   //
   // Redistribution and use in source and binary forms, with or without
   // modification, are permitted provided that the following conditions are met:
   //
   //    * Redistributions of source code must retain the above copyright
   //      notice, this list of conditions and the following disclaimer.
   //
   //    * Redistributions in binary form must reproduce the above copyright
   //      notice, this list of conditions and the following disclaimer in the
   //      documentation and/or other materials provided with the distribution.
   //
   //    * Neither the name of the Willow Garage, Inc. nor the names of its
   //      contributors may be used to endorse or promote products derived from
   //      this software without specific prior written permission.
   //
   // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
   // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   // POSSIBILITY OF SUCH DAMAGE.
   
   #ifndef WAREHOUSE_ROS_QUERY_RESULTS_H
   #define WAREHOUSE_ROS_QUERY_RESULTS_H
   
   #include <warehouse_ros/message_with_metadata.h>
   #include <warehouse_ros/exceptions.h>
   #include <boost/iterator/iterator_facade.hpp>
   
   namespace warehouse_ros
   {
   class ResultIteratorHelper
   {
   public:
     virtual bool next() = 0;
     virtual bool hasData() const = 0;
     virtual Metadata::ConstPtr metadata() const = 0;
     virtual std::string message() const = 0;
     virtual ~ResultIteratorHelper() = default;
   
     typedef boost::shared_ptr<ResultIteratorHelper> Ptr;
   };
   
   template <class M>
   class ResultIterator
     : public boost::iterator_facade<ResultIterator<M>, typename MessageWithMetadata<M>::ConstPtr,
                                     boost::single_pass_traversal_tag, typename MessageWithMetadata<M>::ConstPtr>
   {
   public:
     ResultIterator(ResultIteratorHelper::Ptr results, bool metadata_only);
   
     ResultIterator() = default;
   
   private:
     friend class boost::iterator_core_access;
   
     // Member functions needed to be an iterator
     void increment();
     typename MessageWithMetadata<M>::ConstPtr dereference() const;
     bool equal(const ResultIterator<M>& other) const;
   
     ResultIteratorHelper::Ptr results_;
     bool metadata_only_ = false;
   };
   
   template <class M>
   struct QueryResults
   {
     typedef std::pair<ResultIterator<M>, ResultIterator<M> > range_t;
   };
   
   }  // namespace warehouse_ros
   
   #include "impl/query_results_impl.hpp"
   
   #endif  // include guard