[GHC] #10085: Type families cause wrapper types to disappear without cause

[GHC]

#10085: Type families cause wrapper types to disappear without cause
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        Reporter:  tathougies        |                   Owner:
            Type:  bug               |                  Status:  closed
        Priority:  normal            |               Milestone:
       Component:  Compiler (Type    |                 Version:  7.8.3
  checker)                           |                Keywords:
      Resolution:  invalid           |            Architecture:
Operating System:  Unknown/Multiple  |  Unknown/Multiple
 Type of failure:  GHC rejects       |               Test Case:
  valid program                      |                Blocking:
      Blocked By:                    |  Differential Revisions:
 Related Tickets:                    |
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Changes (by simonpj):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 Yes, glguy is spot on: you cannot partially apply a type family.  This was
 a bug in 7.8 and I have no idea what unpredictable consequences might
 occur if you do.  If you can make your strange behaviour happen with 7.10
 then let's look at it.

 I'm sorry about the bug in 7.8 which has wasted some of your time.  I'll
 close this as invalid (our fault not yours), but do re-open if you can
 make something like this happen without partial application.

 Simon

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10085#comment:2>
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