[ghc-steering-committee] #604: do not let -XScopedTypeVariables imply -XTypeAbstractions, rec: accept

[Joachim Breitner]

Dear committee,

John Ericsson in
https://github.com/ghc-proposals/ghc-proposals/pull/604
proposes an amendment to #448.

I’ll shepherd this myself.

Status Quo:
  ScopedTypeVariables implies TypeAbstractions.
New behavior:
  TypeAbstractions needs to be enabled explicitly.
  (Plus, as a compat feature, ScopedTypeVariables&TypeApplications 
  enable TypeAbstractions, with a deprecation warning upon use.)


John makes a good argument that it’s odd to expand the meaning of an
existing extension like ScopedTypeVariables without need, and the
proposed way sounds good to me, so I recommend to accept this.


This is a minor change and would be good to have clarity soon. If no
discussion happens, I’ll merge in a week. I am particularly keen on
feedback from Richard (original author) and Arnaud (original shepherd),
of course.

Cheers,
Joachim




-- 
Joachim Breitner
  mail at joachim-breitner.de
  http://www.joachim-breitner.de/