termination for FDs and ATs

Ross Paterson ross at soi.city.ac.uk
Thu May 4 10:51:23 EDT 2006


On Thu, May 04, 2006 at 02:00:33PM +0100, Simon Peyton-Jones wrote:
> Actually, it won't.  The spec just says that the function is monomorphic
> in 'a'.  That is, 'a' can be instantiated only one way.  So if f is
> called, say (f True True), then that fixes 'a' to be Bool and all is
> well.

Oops.  Still, if the class can have two parameters, I could define
Result (Maybe a) b = [b] instead of Bool and probably get a contrast
between polymorphism and monomorphism in b.



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