Why isn't this Typeable?

David Feuer david at well-typed.com
Sun Sep 24 11:45:55 UTC 2017

data Foo :: (forall a. a -> Maybe a) -> Type
Neither Foo nor Foo 'Just is Typeable. There seems to be a certain sense to excluding Foo proper, because it can't be decomposed with Fun. But why not Foo 'Just? Is there a fundamental reason, or is that largely an implementation artifact?
David FeuerWell-Typed, LLP
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/ghc-devs/attachments/20170924/6a188855/attachment.html>

More information about the ghc-devs mailing list