[Haskell-cafe] Re: Predicativity?
weihu at cs.virginia.edu
Wed Sep 17 17:03:26 EDT 2008
Thomas Davie <tom.davie <at> gmail.com> writes:
> In your application (id id) you create two instances of id, each of
> which has type forall a. a -> a, and each of which can be applied to a
> different type. In this case, the left one gets applied to the type
> (a -> a) and the right one a, giving them types (a -> a) -> (a -> a)
> and (a -> a) respectively.
Ah, I didn't realize it's because I created two instances of id, but it became
clear immediately after you pointed this out. Thank you, Ryan and Thomas, for
clarifying my confusion.
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