[GHC] #13957: Allow deriving multiparameter type classes with representationally equal arguments

[GHC]

#13957: Allow deriving multiparameter type classes with representationally equal
arguments
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      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 Iceland_jack):

 TODO What if the argument order of `SIEVE` were reversed, as with
 [https://hackage.haskell.org/package/profunctors-5.2/docs/Data-Profunctor-
 Sieve.html Sieve].. let's find a way to allow deriving that as well.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13957#comment:1>
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