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A comment on Toward Go 2. Parent comment

Re:Toward Go 2 by ufo on Friday July 14, 2017 @05:03AM (#14768520)
GHC's Dynamic type can only contain monomorphic values, it can't handle polymorphic stuff.

GHC also considers Dynamic->Dynamic and Int->Int to be incompatible types, which is not quite what one would want in a gradualy typed setting.

Haskell also sidesteps the difficulties that come with mutability in a gradualyly typed setting.

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Re:Toward Go 2 by tome on Friday July 14, 2017 @03:04PM (#14772344)
> GHC's Dynamic type can only contain monomorphic values, it can't handle polymorphic stuff.

Sort of. If you wrap a polymorphic type inside a monomorphic one then it can handle it fine, for example

    data Mono = Mono (forall a b. a -> b -> a)
(But perhaps you know this)
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Re:Toward Go 2 by willtim on Friday July 14, 2017 @06:08AM (#14768710)
I did not mention GHC's Dynamic type. I mentioned GHC's deferred-type errors as an alternative technique to "gradual typing". I believe there were plans to implement a polymorphic version of Dynamic, but it obviously wasn't a high priority. Note that GHC does not require any special type-system extensions to support Dynamic.
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