Class System current status

Ben Rudiak-Gould Benjamin.Rudiak-Gould at cl.cam.ac.uk
Mon May 15 12:04:33 EDT 2006


Johannes Waldmann wrote:
> Ben Rudiak-Gould wrote:
> 
>>>     => Partial p i b | p i -> b  where ...       -- (*)
> 
>> I think it's fine. The "p i b" on the left is effectively a tuple also.
> 
> The problem is that "Partial p i b" is application, while "p i" is not.

That's just it: I don't think "Partial p i b" is an application. The 
typeclass language is a logic language. "((Partial p) i) b" is illegal. 
(Well, GHC accepts it, but I think that's a side effect of the way the 
parser works. Hugs rejects it.)

-- Ben



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