[GHC] #11122: Ambiguous inferred type causes a panic

[GHC]

#11122: Ambiguous inferred type causes a panic
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        Reporter:  tuplanolla        |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  7.10.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #10615            |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

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


Comment:

 In `wip/spj-wildcard-refactor` (shortly to land) I get
 {{{
 T11122.hs:18:18: warning:
     • Found type wildcard ‘_’ standing for ‘Int’
     • In the type signature:
         parser :: Parser _
     • Relevant bindings include
         parser :: Parser Int (bound at T11122.hs:20:1)
 }}}
 Which looks right.

 Ben: can you add this as a regression test please when you land that big
 patch?

 Simon

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11122#comment:4>
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