[GHC] #14975: Refactor (Maybe Coercion)

[GHC]

#14975: Refactor (Maybe Coercion)
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        Reporter:  tdammers          |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11735            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by tdammers):

 A few questions that pop up:

 - Shouldn't this go in `TyCoRep.hs`, and then be re-exported from
 `Coercion.hs`, like the other coercion-related types?
 - Defined like this (`*` rather than `* -> *`), we'll miss out on
 `Functor`, `Applicative`, `Alternative`, etc.; are we going to regret
 this?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14975#comment:1>
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