[GHC] #13705: Failure of improvement for type-family dependencies

[GHC]

#13705: Failure of improvement for type-family dependencies
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  merge
        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:  indexed-
                                     |  types/should_compile/T13705
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

 * status:  new => merge
 * testcase:   => indexed-types/should_compile/T13705


Comment:

 Might be worth merging, but definitely not essential.

 I ended up refactoring the unifer to make the environment an explicit
 parameter, so that it's easier to use in guards.  So the patch is bigger
 than it "needs" to be.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13705#comment:5>
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