[GHC] #10653: PatternSynonyms should be imported/exported as part of the wildcard notation

[GHC]

#10653: PatternSynonyms should be imported/exported as part of the wildcard
notation
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        Reporter:  gridaphobe        |                   Owner:
            Type:  feature request   |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.11
      Resolution:                    |                Keywords:  pattern
                                     |  synonyms
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 simonpj):

 Yes, you do have to import-chase to figure out which ''subset'' of data
 constructors are imported by `T(..)`. But there's an upper bound: it can
 import no more than all the constructors.

 With the new proposal, ''any'' old new pattern synonym could be brought
 into scope by `T(..)`.  That is new.  Maybe it's not terrible, but it's
 new.

 Maybe one would want to associate more things with `T`?  Such as a family
 of functions over `T`, whether or not they are pattern synonyms?

 Anyway I don't feel terribly strongly about all this ''provided'' it can
 all be resolved by the renamer (ie not involving type inference).  By all
 means write a wiki page, seek feedback etc.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10653#comment:15>
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