[m-dev.] type classes --- thoughts?

[Tyson Richard DOWD]

> 
> Zoltan Somogyi, you wrote:
> > 
> > I think univ should be like Ada's limited private; only permitted operation
> > is assign (and univ_to_type of course).
> 
> If we don't provide some way for arg to work on univ, then it is
> going to be impossible to use arg and functor to recursively traverse a
> term, since arg itself returns a list(univ).

Well, a univ, not a list(univ). 

> 
> Thus, we need to provide a way to do this, even if it requires some dynamic
> checking.

Yep, you need to be able to dynamically check that the univ is 
actually a type that belongs to the `decomposable' class. This might be
tricky.

-- 
       Tyson Dowd           # "Well, let's just say, 'if your VCR is
                            #  still blinking 12:00, you don't
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