[GHC] #15546: Display coaxiom branch incompatibilities in GHCi

[GHC]

#15546: Display coaxiom branch incompatibilities in GHCi
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        Reporter:  mniip             |                Owner:  mniip
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  GHCi              |              Version:  8.4.3
      Resolution:                    |             Keywords:  TypeFamilies,
                                     |  GHCi
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D5097
       Wiki Page:                    |
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Comment (by simonpj):

 >  I thus agree that the ability to print out incompatibilities is
 sometimes helpful for users, not just implementors.

 OK, thanks.  Now I understand.  I agree.

 mnip: in the code, can you add a Note with an example of what the
 incompatibility stuff looks like when printed out; and some version of
 Richard's comments in comment:9 to explain why it might be useful for
 users to see this information?

 Also are the equations 0-indexed or 1-indexed? The Note, and the manual
 entry about the flag, should say.

 Also can you modify the manual section that Richard points to in comment:9
 so that it mentions the existence of the flag to show compatibilities?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15546#comment:10>
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