[GHC] #14131: Difference between newtype and newtype instance

[GHC]

#14131: Difference between newtype and newtype instance
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        Reporter:  Iceland_jack      |                Owner:  RyanGlScott
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  TypeFamilies
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #7938, #9574,     |  Differential Rev(s):  Phab:D3872
  #13985                             |
       Wiki Page:                    |
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Comment (by simonpj):

 > We still need the typechecker test for comment:8.

 What I mean is: the renaner cannot reject the right set of programs (see
 comment:8).  So the renamer must err on the side of acceptance, and leave
 the type checker to reject programs where variables appear on the RHS that
 are not bound on the left.

 > But perhaps I should first do this refactoring in a separate commit

 Sounds good to me.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14131#comment:11>
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