Why no multiple-dispatch?

[bearophile via Digitalmars-d-learn]

Aerolite:

> I was surprised to learn yesterday that D does not actually
> support Multiple-Dispatch, also known as Multimethods. Why is
> this? Support for this feature is already present in Scala, C#
> 4.0, Groovy, Clojure, etc... Would it not make sense for D to
> remain competitive in this regard?

I think a hypothetical way for D to become more competitive is to 
have less OOP ;-) D things like onCmp() for classes are ugly and 
not easy to write correctly. Perhaps Rust solves (avoids) such 
problems better, and with much less complexity (but Rust will 
have other problems of course, like the excessive amount of type 
inference, because no one designs very good languages).

Bye,
bearophile