mcamurri's profile - activity

Hi all, I'm subscribing to a callback which takes arguments by using the boost::bind structure:

nh_.subscribe<MsgT>(topic, 1000,  boost::bind(&ROSFrontEnd::callback<MsgT>, this, _1, sensor_id));

where the callback signature is the follwing:

template <class MsgT>
void callback(boost::shared_ptr<MsgT const> msg,
              const SensorId& Key);

Now I want to extend the subscription by adding transport hints, like so:

nh_.subscribe<MsgT>(topic, 1000,  boost::bind(&ROSFrontEnd::callback<MsgT>, this, _1, sensor_id), ros::TransportHints().tcpNoDelay());

but I get a compilation error saying that there is no such signature for subscribe.

What is the correct way to subscribe to a callback taking arguments and passing transport hints as well?

The code worked just fine without the transport hints. I'm using Ubuntu 16.04 with ROS Kinetic.

UPDATE Here is a MCVE with the full error listing:

#include <boost/shared_ptr.hpp>
#include <boost/bind.hpp>
#include <std_msgs/String.h>
#include <ros/node_handle.h>
#include <ros/subscriber.h>
#include <ros/transport_hints.h>

class TransportHintsTest {
public:
    typedef std::string SensorId;
public:

    TransportHintsTest(ros::NodeHandle& nh) : nh_(nh){

        SensorId id = "string";
        sub = nh_.subscribe<std_msgs::String>("mytopic", 10, boost::bind(&TransportHintsTest::callback<std_msgs::String>,
                                                                         this,
                                                                         _1,
                                                                         id),
                                              ros::TransportHints().tcpNoDelay()); // without this last argument, compiles fine
    }

    template <class MsgT>
    void callback(boost::shared_ptr<MsgT const> msg, const SensorId& sensor_id){
    }

private:
    ros::Subscriber sub;
    ros::NodeHandle nh_;
};

int main(int argc, char** argv) {
    ros::init(argc, argv,"transport_hint_test");
    ros::NodeHandle nh;
    TransportHintsTest node(nh);
}

The error says:

/home/mcamurri/catkin_ws/src/transport_hint_test/src/transport_hints.cpp: In constructor ‘TransportHintsTest::TransportHintsTest(ros::NodeHandle&)’:
/home/mcamurri/catkin_ws/src/transport_hint_test/src/transport_hints.cpp:20:81: error: no matching function for call to ‘ros::NodeHandle::subscribe(const char [8], int, boost::_bi::bind_t<void, boost::_mfi::mf2<void, TransportHintsTest, boost::shared_ptr<const std_msgs::String_<std::allocator<void> > >, const std::__cxx11::basic_string<char>&>, boost::_bi::list3<boost::_bi::value<TransportHintsTest*>, boost::arg<1>, boost::_bi::value<std::__cxx11::basic_string<char> > > >, ros::TransportHints&)’
                                               ros::TransportHints().tcpNoDelay());
                                                                                 ^
In file included from /home/mcamurri/catkin_ws/src/transport_hint_test/src/transport_hints.cpp:4:0:
/opt/ros/kinetic/include/ros/node_handle.h:402:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(M), T*, const ros::TransportHints&)
   Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(T::*fp)(M), T* obj, 
              ^
/opt/ros/kinetic/include/ros/node_handle.h:402:14: note:   template argument deduction/substitution failed:
/home/mcamurri/catkin_ws/src/transport_hint_test/src/transport_hints.cpp:20:81: note:   mismatched types ‘void (T::*)(std_msgs::String_<std::allocator<void> >)’ and ‘boost::_bi::bind_t<void, boost::_mfi::mf2<void, TransportHintsTest, boost::shared_ptr<const std_msgs::String_<std::allocator<void> > >, const std::__cxx11::basic_string<char>&>, boost::_bi::list3<boost::_bi::value<TransportHintsTest*>, boost::arg<1>, boost::_bi::value<std::__cxx11::basic_string<char> > > >’
                                               ros::TransportHints().tcpNoDelay());
                                                                                 ^
In file included from /home/mcamurri/catkin_ws/src/transport_hint_test/src/transport_hints.cpp:4:0:
/opt/ros/kinetic/include/ros/node_handle.h:413:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe ...