[GHC] #12085: Premature defaulting and variable not in scope

[GHC]

#12085: Premature defaulting and variable not in scope
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        Reporter:  Iceland_jack      |                Owner:
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
                                     |  TypeApplications
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 For the first part, `:type` instantiates, defaults, and re-generalises,
 because `:type <expr>` works on an arbitrary expression `<expr>`.

 You may want `:info`.  See the extensive debate on #11376.

 So I think everything is behaving as designed there.  (You may want to
 propose a design change.)

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12085#comment:1>
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