A template for method forwarding?

[Simen Kjaeraas]

On Fri, 12 Dec 2008 21:08:51 +0100, Bill Baxter <wbaxter at gmail.com> wrote:

> Let's say you want to use object composition instead of inheritance.
> Now you want to forward half-a-dozen method from the new to class to
> the composed class, like so:
>
> class NewClass
> {
>      ImplT implementor;
>      ...
>      // Do some method forwarding
>      void func1(int a, float b) { implementor.func1(a,b); }
>      string func2(string s) { return implementor.func2(s); }
>      T aTemplate(T)(T val, T[] arr) { return implementor!(T)(val,arr); }
>      ...
> }
>
> It becomes pretty tedious to type all these things out, and if the
> base class changes a method signature, you have to remember to do it
> in the parent class too.
> So the challenge is to write some kind of template that does the
> necessary argument deduction to implement a forwarder just by
> mentioning the name of the method and the object to forward to.
> Something like this perhaps for the usage syntax:
>
>     mixin call_forward!(implementor, "func1");
>     mixin call_forward!(implementor, "func2");
>     mixin call_forward!(implementor, "aTemplate");
>
> Is it possible?  Somebody must have done something like this already.
>
> --bb

Wouldn't opDot do what you want here?

-- 
Simen