[Haskell-cafe] confusion about 'instance'....

Jules Bean jules at jellybean.co.uk
Thu Jan 10 11:05:11 EST 2008

Nicholls, Mark wrote:
>> Classes are groups of types. Sets of types. Classifications of types.
> I had them down as an n-ary relation on types....someone's said
> something somewhere that's made me question that...but I think I
> misinterpreted them....so I may default back to n-ary relation.

Yes, and 1-ary relations are sets. And haskell98 only supports unary 
type classes, and all our discussion so far had been about unary type 

But, since you mention it, yes MPTCs are n-ary relations.


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