[Haskell-cafe] Limits of deduction

Jules Bean jules at jellybean.co.uk
Mon May 14 10:29:49 EDT 2007


Christopher L Conway wrote:
>
> The inference assigns y the type (t1 -> t1) even though it is assigned
> the value 3?
>


Yes, because type classes are open, and maybe you will demonstrate some 
way to make t1->t1 an instance of Num.

Note the Num (t1 -> t1) constraint in the type...


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