Implied GHC extensions (in HEAD)

Gabor Greif ggreif at
Fri Nov 6 16:27:30 UTC 2015

Hi devs,

when compiling a snippet of code (which I have written using GHC HEAD)
with GHC 7.10.2 (from the platform) I got errors about missing
extension pragmas. I had to add two:

> {-# LANGUAGE ViewPatterns, KindSignatures, GADTs, PolyKinds, StandaloneDeriving, FlexibleContexts, FlexibleInstances, ScopedTypeVariables, TypeFamilies, PatternSynonyms, FunctionalDependencies, RankNTypes, UndecidableInstances #-}
> {-# LANGUAGE DataKinds, TypeOperators #-} -- 7.10??

Looks like the implications have been extended in 7.11.

I guess PolyKinds now implies DataKinds, but cannot think of what
implies TypeOperators.

Was this change by design or by accident?

Any ideas?



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