[GHC] #13637: Printing type operators adds extraneous parenthesis

[GHC]

#13637: Printing type operators adds extraneous parenthesis
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        Reporter:  darchon           |                Owner:  alanz
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by nfrisby):

 I agree that this ticket's bug should be fixed. The {{{We don't keep the
 fixity of type operators in the operator}}} quoted in comment:3 above is
 the root problem, if I understand correctly.

 I'm writing a plugin for type-level sets, and the extra parentheses makes
 the syntax much more difficult to read than it should be. {{{((('Empty :*
 a) :* b) :* c)}}} is worse than {{{'Empty :* a :* b :* c}}}.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13637#comment:4>
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