Dynamic language

[F i L]

Adam D. Ruppe wrote:
> import std.variant;
> struct Extendable {
>     Variant[string] properties;
>     Variant opDispatch(string name)() {
>        return properties[name];
>     }
>     Variant opDispatch(string name, T)(T t) {
>        properties[name] = t;
>        return properties[name];
>     }
> }
>
> void main() {
>     auto a = Extendable();
>     a.sweet = 10;
>     a.cool = { a.sweet = a.sweet + 1; } // could probably fix 
> ++ too..
>     // fails with std.variant but the language *could* do it
>     a.cool(); // exercise for the reader: maek this work! Gotta 
> add opCall.
> }

Alright I give up dammit! How do you use opCall() to make 
a.cool() work?