maybe "extremely late binding" would be more appropriate? it's true that usually "dynamic dispatch" means a vtable, but i think this is dynamic dispatch in spirit - in fact "dispatching" messages to implementations is pretty much the only thing a closure-object does :) i chose to write the impls inline, so they're p much impossible to reuse, but that's not required.

> you can't have a Point3 value that uses Point's implementation of 'x' and its own implementation of 'toString' under this example.

you can't do much of anything under this this example! i didn't think a whole object system would fit in a HN comment, i intended it to be minimal :)