Делегаты С++11

[nick_marcevich2]

...или аналог bind своими руками.

template<typename return_type, typename... params>
class Delegate
{
    typedef return_type (*Type)(void* callee, params...);
public:
    Delegate(void* callee, Type function)
        : fpCallee(callee)
        , fpCallbackFunction(function) {}

    template <class T, return_type (T::*TMethod)(params...)>
    static Delegate from_function(T* callee)
    {
        Delegate d(callee, &methodCaller<T, TMethod>);
        return d;
    }

    return_type operator()(params... xs) const
    {
        return (*fpCallbackFunction)(fpCallee, xs...);
    }

private:

    void* fpCallee;
    Type fpCallbackFunction;

    template <class T, return_type (T::*TMethod)(params...)>
    static return_type methodCaller(void* callee, params... xs)
    {
        T* p = static_cast<T*>(callee);
        return (p->*TMethod)(xs...);
    }
};

Usage

class A
{
public:
    int foo(int x)
    {
        return x*x;
    }
    int bar(int x, int y, char a)
    {
        return x*y;
    }
};
int main()
{
    A a;
    auto d = Delegate<int, int>::from_function<A, &A::foo>(&a);
    auto d2 = Delegate<int, int, int, char>::from_function<A, &A::bar>(&a);
    printf("delegate with return value: d(42)=%d\n", d(42));
    printf("for d2: d2(42, 2, 'a')=%d\n", d2(42, 2, 'a'));
    return 0;
}

src

Alexandrescu about variadic templates: http://channel9.msdn.com/Events/GoingNative/GoingNative-2012/Variadic-Templates-are-Funadic