如何使用 boost::bind 附加参数?

How to append parameter using boost::bind?

本文关键字：参数 bind 何使用 boost 更新时间：2023-10-16

我正在尝试使用 boost：：bind 将另一个参数附加到 ROS 订阅者回调函数，但我无法弄清楚我的代码出了什么问题：

这是回调函数签名：

void setDigitalOutputCallback(const std_msgs::Bool& cmd, int index);

在通常的 ROS 回调中，只有第一个 (cmd( 参数(。然后我尝试使用以下方法设置回调：

digitalOutputSub[i] = nh.subscribe(topicName, 1, boost::bind(setDigitalOutputCallback, _1, i));

示例代码：

#include "std_msgs/Bool.h"
#include "ros/ros.h"
void setDigitalOutputCallback(const std_msgs::Bool& cmd, int index) {
}
int main(int argc, char *argv[])
{
ros::init(argc, argv, "blaster_driver");
ros::NodeHandle nh;
ros::Subscriber digitalOutputSub;
std::string topicName = "test";
int i = 1;
digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
return 0;
}

编译器在这一行上给出了很多错误，但我不明白那里有什么问题：

test.cpp: In function ‘int main(int, char**)’: test.cpp:15:100: error: no matching function for call to ‘ros::NodeHandle::subscribe(const char*, int, boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >)’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:401:14: 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/indigo/include/ros/node_handle.h:401:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(M)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:412:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(M) const, T*, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(T::*fp)(M) const, T* obj,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:412:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(M) const’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:464:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(const boost::shared_ptr<const M>&), T*, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:464:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(const boost::shared_ptr<const M>&)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:474:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(const boost::shared_ptr<const M>&) const, T*, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:474:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(const boost::shared_ptr<const M>&) const’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:528:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(M), const boost::shared_ptr<U>&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(T::*fp)(M),
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:528:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(M)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:539:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(M) const, const boost::shared_ptr<U>&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(T::*fp)(M) const,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:539:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(M) const’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:593:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(const boost::shared_ptr<const M>&), const boost::shared_ptr<U>&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:593:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(const boost::shared_ptr<const M>&)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:604:14: note: candidate: template<class M, class T> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (T::*)(const boost::shared_ptr<const M>&) const, const boost::shared_ptr<U>&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:604:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (T::*)(const boost::shared_ptr<const M>&) const’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:655:14: note: candidate: template<class M> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (*)(M), const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(*fp)(M), const TransportHints& transport_hints = TransportHints())
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:655:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (*)(M)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:703:14: note: candidate: template<class M> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, void (*)(const boost::shared_ptr<const M>&), const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, void(*fp)(const boost::shared_ptr<M const>&), const TransportHints& transport_hints = TransportHints())
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:703:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   mismatched types ‘void (*)(const boost::shared_ptr<const M>&)’ and ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:749:14: note: candidate: template<class M> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, const boost::function<void(const boost::shared_ptr<const M>&)>&, const VoidConstPtr&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, const boost::function<void (const boost::shared_ptr<M const>&)>& callback,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:749:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’ is not derived from ‘const boost::function<void(const boost::shared_ptr<const M>&)>’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:798:14: note: candidate: template<class M, class C> ros::Subscriber ros::NodeHandle::subscribe(const string&, uint32_t, const boost::function<void(C)>&, const VoidConstPtr&, const ros::TransportHints&)    Subscriber subscribe(const std::string& topic, uint32_t queue_size, const boost::function<void (C)>& callback,
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:798:14: note:   template argument deduction/substitution failed: test.cpp:15:100: note:   ‘boost::_bi::bind_t<void, void (*)(const std_msgs::Bool_<std::allocator<void> >&, int), boost::_bi::list2<boost::arg<1>, boost::_bi::value<int> > >’ is not derived from ‘const boost::function<void(C)>’   digitalOutputSub = nh.subscribe(topicName.c_str(), 1, boost::bind(setDigitalOutputCallback, _1, i));
                              ^ In file included from /opt/ros/indigo/include/ros/ros.h:45:0,
from test.cpp:2: /opt/ros/indigo/include/ros/node_handle.h:835:14: note: candidate: ros::Subscriber ros::NodeHandle::subscribe(ros::SubscribeOptions&)    Subscriber subscribe(SubscribeOptions& ops);
^~~~~~~~~ /opt/ros/indigo/include/ros/node_handle.h:835:14: note:   candidate expects 1 argument, 3 provided

从文档中可以看出，您似乎要使用以下重载：

Subscriber ros::NodeHandle::subscribe(
const std::string & topic,
uint32_t queue_size,
const boost::function<void(C)> &    callback,
const VoidConstPtr &    tracked_object = VoidConstPtr(),
const TransportHints &  transport_hints = TransportHints() 
)

但是您没有正确的匹配，请尝试将boost::function创建为变量：

boost::function<void (const std_msgs::Bool&)> f =
boost::bind(setDigitalOutputCallback, _1, i);
digitalOutputSub = nh.subscribe(topicName.c_str(), 1, f);

不确定是否不必指定模板参数：

digitalOutputSub = nh.subscribe<std_msgs::Bool>(topicName.c_str(), 1, f);

我认为topicName传递为std::string并且可能会i(subscribe的第二个参数(，因为unsigned会有所帮助。