[GHC] #10756: Allow users to indicate inaccessible patterns

[GHC]

#10756: Allow users to indicate inaccessible patterns
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        Reporter:  edsko             |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.2
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by goldfire):

 Thanks for writing that up.

 I like it. My only complaint is the choice of the word `impossible`, which
 becomes a full-fledged keyword under this proposal. If someone wants to
 use `ImpossibleCases` and they import a symbol named `impossible`, can
 they use it? I suppose using it qualified wouldn't conflict. And no
 exported symbol named `impossible` comes up at
 http://www.stackage.org/lts-2.22/hoogle?q=impossible

 I don't have a better suggestion among the set of keywords/keyoperators.

 So I vote +1 for the proposal exactly as is.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10756#comment:5>
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