使用Boost C ++重新绑定类成员函数

Question

The example belows shows a class member binding with boost bind. This works good but what if i want to rebind f to another class rebind2. I did not found any solution and calling bind with boost function didn't work. Any idea how rebinding a class member function could work.

class RebindTest {
public:
    std::string name;

    RebindTest(std::string n){
        name = n;
    }

    void print(){
        std::cout << name << std::endl;
    }
};

int main(int argc, char **argv){
    RebindTest rebind1("rebind1");
    RebindTest rebind2("rebind2");

    typedef void (RebindTest::*fPtr)(void);

    boost::function<void(void)> f;
    f = boost::bind(&RebindTest::print,rebind1);
    f();
}

Answer 1

How about creating an intermediate binding? I'm using the standard library here, but I'm sure you can substitute a Boost solution if you have to:

auto BoundPrint = std::mem_fn(&RebindTest::print);

// can use: BoundPrint(rebind1), BoundPrint(rebind2), etc.

std::function<void()> f = std::bind(BoundPrint, rebind1);

// assign new binding
f = std::bind(BoundPrint, rebind2);

I'm not sure if this really solves any problem. You can always just write the complete bind expression again:

f = std::bind(&RebindTest::print, rebind2);

But maybe if your real use case has a lot of common, bound arguments, or bound arguments that you only want to evaluate once, then an intermediate binding may be useful.