[GHC] #5144: Pattern synonyms

[GHC]

#5144: Pattern synonyms
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        Reporter:  simonpj           |            Owner:  cactus
            Type:  feature request   |           Status:  new
        Priority:  normal            |        Milestone:  _|_
       Component:  Compiler          |          Version:
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by simonpj):

 Replying to [comment:24 igloo]:
 > I haven't followed the design, but I would expect exporting "pattern P"
 to either be an error ("P is a data constructor, not a pattern") or to
 export P in a way that allows it only to be used as a pattern, not an
 expression.

 Well in the design here [wiki:PatternSynonyms], `pattern P` exports P for
 use both in patterns and expressions.  By all means suggest alternative
 designs; that's what this thread is all about.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5144#comment:26>
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