Steven Schveighoffer Wrote:
> opDot is useful if you want to make a 'wrapper' type. That is, you want to
> mimic another type, but you want to slightly alter the behavior. opDot
> allows you to 'inherit' all the member functions and fields from the wrapped
> type. For example, if I wanted to create a wrapper type that added a
> 'blahblah' integer to the type, I could do this:
>
> struct AddBlahBlah(T)
> {
> T _t;
> int blahblah;
>
> T *opDot() { return &_t;}
> }
>
> Now, if I declare an AddBlahBlah!(C) and class C has a member foo():
>
> C c;
> AddBlahBlah!(C) abb = AddBlahBlah!(C)(c);
>
> abb.foo(); // translates to abb.opDot().foo()
> abb.blahblah = 5; // sets abb.blahblah to 5, doesn't affect _t
>
> The goal of opDot is to allow one to create types that wrap other types that
> look almost exactly the same without much effort. For example, the
> std.typecons.Rebindable type allows one to create a rebindable const or
> invariant class reference while forwarding all member accesses to the
> underlying invariant or const instance. This feature is used for extending
> the type system without having to extend the language, allowing compiler
> enforcement of specific design aspects without defining them in the
> compiler.
>
> Normal developers will most likely never need to define opDot.
>
> -Steve
>
>
Thank you very much Steven!
Luca
