ANNOUNCE: GHC 7.0.1 Release Candidate 1
simonpj at microsoft.com
Wed Sep 29 22:16:15 EDT 2010
| Except I don't know how to write a type signature for this.
| The value 's' passed in is bound by pattern matching on this guy's constructor:
| data Stream a = forall s. Stream (s -> Step s a) !s Int
| in the top-level function, so I don't even know if it has a type I can name.
You can bind the type variable using a pattern type signature
case x of
Stream fun (state :: s) n -> ...
This should bind the type variable 's'.
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