The following code causes cl.exe to crash (MS VS2005).
I am trying to use boost bind to create a function to a calls a method of myclass:
#include "stdafx.h"
#include <boost/function.hpp>
#include <boost/bind.hpp>
#include <functional>
class myclass {
public:
void fun1() { printf("fun1()\n"); }
void fun2(int i) { printf("fun2(%d)\n", i); }
void testit() {
boost::function<void ()> f1( boost::bind( &myclass::fun1, this ) );
boost::function<void (int)> f2( boost::bind( &myclass::fun2, this ) ); //fails
f1();
f2(111);
}
};
int main(int argc, char* argv[]) {
myclass mc;
mc.testit();
return 0;
}
What am I doing wrong?
Use the following instead:
boost::function<void (int)> f2( boost::bind( &myclass::fun2, this, _1 ) );
This forwards the first parameter passed to the function object to the function using place-holders - you have to tell Boost.Bind how to handle the parameters. With your expression it would try to interpret it as a member function taking no arguments.
See e.g. here or here for common usage patterns.
Note that VC8s cl.exe regularly crashes on Boost.Bind misuses - if in doubt use a test-case with gcc and you will probably get good hints like the template parameters Bind-internals were instantiated with if you read through the output.