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#ifndef MESSAGE_FILTERS_PASSTHROUGH_H
#define MESSAGE_FILTERS_PASSTHROUGH_H

#include "simple_filter.h"

#include <vector>

namespace message_filters
{
/**
 * \brief Simple passthrough filter.  What comes in goes out immediately.
 */
template<typename M>
class PassThrough : public SimpleFilter<M>
{
public:
  typedef boost::shared_ptr<M const> MConstPtr;
  typedef ros::MessageEvent<M const> EventType;

  PassThrough()
  {
  }

  template<typename F>
  PassThrough(F& f)
  {
    connectInput(f);
  }

  template<class F>
  void connectInput(F& f)
  {
    incoming_connection_.disconnect();
    incoming_connection_ = f.registerCallback(typename SimpleFilter<M>::EventCallback(boost::bind(&PassThrough::cb, this, _1)));
  }

  void add(const MConstPtr& msg)
  {
    add(EventType(msg));
  }

  void add(const EventType& evt)
  {
    this->signalMessage(evt);
  }

private:
  void cb(const EventType& evt)
  {
    add(evt);
  }

  Connection incoming_connection_;
};

} // namespace message_filters

#endif // MESSAGE_FILTERS_PASSTHROUGH_H

