Re: [Boost-users] Function pointers vs boost.function

From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-09-02 16:55:17

AMDG

Kurt Kohler wrote:
> I have some code that uses pointers to member functions (not
> boost.function). It compiles and works fine. But when I tried to convert
> the code to use boost.function, I got a mess of errors.
> I know I'm doing something wrong, but I have no idea what it is. A clue
> would be greatly appreciated.
>   

When you use Boost.Function with member functions,
you need to pass "this" as the first argument.

#include <boost/function.hpp>

struct X
{
    double f(double x) { return x; }
    double g(double x) { return -x; }

    typedef boost::function<double(X*, double)> ftype;
   
    double call(ftype func, double x)
    {
        return func(this, x);
    }
};

int main(int argc, char *argv[])
{
    X x;
    x.call(&X::f, 1.0);
    x.call(&X::g, 2.0);
}

In Christ,
Steven Watanabe