[GHC] #14570: Untouchable error arises from type equality, but not equivalent program with fundeps

[GHC]

#14570: Untouchable error arises from type equality, but not equivalent program
with fundeps
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        Reporter:  lexi.lambda       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by dfeuer):

 * cc: dfeuer (added)


Comment:

 At the least, this is a rather poor error message. I don't think it's
 terribly reasonable to expect users to read and understand near-cutting-
 edge papers about type inference in order to understand what they've done
 wrong and how they might fix it.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14570#comment:3>
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