Single controller template

[mikepurvis]

As hinted at in #299 (comment), with C++11 it's now possible to achieve all features of MultiInterfaceController with a single Controller template that doesn't break the existing API. You basically get an init() function which includes pointers to all the hardware interfaces you specify in the template instantiation, eg:

class VelEffController : public controller_interface::Controller<VelocityJointInterface, EffortJointInterface>
{
public:
  bool init(VelocityJointInterface* v, EffortJointInterface* e, ros::NodeHandle &n) override;
}

With a single argument, this is the same as the legacy Controller usage. For compatibility with existing MultiInterfaceController, a deprecated adapter header is supplied which populates a reduced RobotHW as it worked before.

I'd propose this as a change for ROS Melodic, and removing the now deprecated multi_interface_controller.h in ROS N.

---

Note that the diff given here is pretty unhelpful. I'd suggest reviewing the new versions of the headers directly:

https://github.com/mikepurvis/ros_control/blob/single-controller-template/controller_interface/include/controller_interface/controller.h
https://github.com/mikepurvis/ros_control/blob/single-controller-template/controller_interface/include/controller_interface/multi_interface_controller.h

---

@adolfo-rt in particular I'm interested to hear from, as he was the original author of MultiInterfaceController, upon which this work builds heavily.

[iwanders]

Clang-7 complains about class here:

robothw_interfaces.h:60:68: error: typedef 'value_type' cannot be referenced with a class specifier
  std::copy(val.begin(), val.end(), std::ostream_iterator<class T::value_type>(ss, sdp.c_str()));
                                                                   ^

using typename works without problems.

[jasonimercer]

Also dies with Clang 6

[bmagyar]

What is the state of this? Is there something missing to merge?

…

On Fri, 31 Aug 2018, 16:44 Ivor Wanders, ***@***.***> wrote: ***@***.**** commented on this pull request. ------------------------------ In controller_interface/include/controller_interface/internal/robothw_interfaces.h <#302 (comment)> : > +namespace internal +{ + +template <class T> +inline std::string enumerateElements(const T& val, + const std::string& delimiter, + const std::string& prefix, + const std::string& suffix) +{ + std::string ret; + if (val.empty()) {return ret;} + + const std::string sdp = suffix+delimiter+prefix; + std::stringstream ss; + ss << prefix; + std::copy(val.begin(), val.end(), std::ostream_iterator<class T::value_type>(ss, sdp.c_str())); Clang-7 complains about class here: robothw_interfaces.h:60:68: error: typedef 'value_type' cannot be referenced with a class specifier std::copy(val.begin(), val.end(), std::ostream_iterator<class T::value_type>(ss, sdp.c_str())); ^ using typename works without problems. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#302 (review)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADXH4ZE9vhWknFYDhrxItUp0jCpLLWUPks5uWVnNgaJpZM4SAnXL> .

[mikepurvis]

Closed in favour of #387.