Hypothetical reasoning in type classes

Ashley Yakeley ashley at semantic.org
Sun Nov 16 11:03:50 EST 2003

In article <20031113054018.GA5577 at eecs.harvard.edu>,
 Ken Shan <ken at digitas.harvard.edu> wrote:

> Just today (and not
> only today) I wanted to write instance definitions like
>     instance (forall a. C a => D a) => E [a] where ...

I've wanted this for awhile, in both class and instance declarations.

Ashley Yakeley, Seattle WA

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