> My functional languages knowledge is a bit rusty nowadays, but would type
> inferrence give us type safety in Ruby?  After all (considering
> overloading) there are enough situations where type inferrence would not
> be able to come up with a completely typed signature.

There's some discussion of this in "Dynamic vs. Static Optimization
Techniques for Object-Oriented Languages" by Urs Höìzle & Ole Agesen.
Their static optimization technique is static type inference. I can't
really remember the conclusions, except that they certainly didn't
manage to infer all types.

-- George