[GHC] #13401: GHCi gives conflicting information about visible type application

[GHC]

#13401: GHCi gives conflicting information about visible type application
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        Reporter:  crockeea          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              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:  #11376, #11975    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by crockeea):

 I **really** appreciate your explanation.

 I frequently use GHCi to learn about my program, and it's extremely
 unhelpful when it lies to me (see
 [http://chat.stackoverflow.com/transcript/message/35984292#35984292 this]
 for another example.) Therefore it seems like type application visibility
 information should ''only'' be displayed with lazy constraint
 instantiation, i.e., when the `+v` option is used. Then there's no
 convoluted explanation needed, and more importantly, you will always get
 correct information.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13401#comment:5>
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