[GHC] #16110: Explicit foralls in associated type family defaults are completely ignored?

[GHC]

#16110: Explicit foralls in associated type family defaults are completely ignored?
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC accepts       |  Unknown/Multiple
  invalid program                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 > So we really know their kinds from the type family declaration. There is
 no need to be able to write their kinds in the default equation.  So
 perhaps the best way forward is just to remove the featurette.

 I agree.

 And let's update the proposal to match.

 We should also document whatever we decide (including the alpha-varying
 bit) in the user manual

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16110#comment:6>
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