Simon Peyton-Jones simonpj at
Tue Nov 21 03:18:19 EST 2006

| Well, for one thing I don't like the idea of a "list" of potential
| defaults.  My suggestion is that there should be a single default type
| per class.  If more than one class is involved, then either their
| defaults should agree, or only one of them in fact declares a default.

Ah, I missed that.  Suppose I have

        default Eq Integer
        default Fractional Float

and I have (Eq a, Fractional a).  Does 'a' resolve to Integer or to Float?  Perhaps a few examples on the proposal page would be useful for readers?


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