[m-rev.] diff: fundeps, polymorphic instances

[Ralph Becket]

Mark Brown, Sunday, 29 October 2006:
> Estimated hours taken: 16
> Branches: main
> 
> Support polymorphic instances of typeclasses with functional dependencies.
> We do this by allowing type variables in the range arguments, which must be
> distinct according to existing typeclass restrictions, to be determined
> from type variables in the domain arguments by the functional dependencies
> on the instance constraints.

This suggests to me that you are allowing 

:- instance foo(list(T), T) where ...

given that

:- typeclass foo(T1, T2) <= (T1 -> T2), ...

Which would be wonderful.  But that isn't illustrated in your example :-(
Have I misunderstood your change?

-- Ralph
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