[Types-sig] types, functional stuff.

[JOrendorff@ixl.com]

> > The language doesn't need them as built-ins.
> 
>         Yes it does. Your implementation is the same as mine,
> and it doesn't work for the same reason: we both use delagation.
> This binds the result to the _current_ definition of a function,
> not the definition at the point of call.
> 
>         For actual functions, this is no problem. They're
> immutable. But the compose object is not. It's a class instance
> whose definition can be changed by changing the args list.

So don't change the args list.

-- 
Jason