[GHC] #12872: Pattern synonyms allow multiple type signatures but only use the first

GHC ghc-devs at haskell.org
Wed Nov 23 13:27:45 UTC 2016


#12872: Pattern synonyms allow multiple type signatures but only use the first
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        Reporter:  jophish           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC accepts       |  Unknown/Multiple
  invalid program                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by mpickering):

 This is fixed in HEAD.

 {{{
 [1 of 1] Compiling Pattern          (.hs -> .o)

 test.hs:5:10: error:
     Duplicate pattern synonym signatures for ‘Foo’
     at test.hs:4:10-12
        test.hs:5:10-12
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12872#comment:1>
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