Tightening up on inferred type signatures

adam vogt vogt.adam at gmail.com
Mon Apr 21 20:57:00 UTC 2014

] GHC generally obeys this rule
] ·         If GHC infers a type f::type, then it’s OK for you to add a type
] signature saying exactly that.

That rule suggests that -XScopedTypeVariables should be on by default,
and that you shouldn't need a forall to bring the type variables into
scope. I imagine that would lead to harder-to-fix breakage than #8883,
but on the other hand type signatures in let/where are pretty rare.


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