[GHC] #14832: QuantifiedConstraints: Adding to the context causes failure

[GHC]

#14832: QuantifiedConstraints: Adding to the context causes failure
-------------------------------------+-------------------------------------
        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
                                     |  QuantifiedConstraints wipT2893
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by simonpj):

 > Is there hope for the user to guide this process

 You want to write a ''term-level'' function that can be used a theorem in
 solving ''type-level'' constraints.  This also came up, I think, in
 #14822.

 Of course, this is much what happens in many proof assistants.  Perhaps we
 can learn from them.  Personally, I don't see a direct way to do this; but
 perhaps others with a broader perspective, and a bit more time, might do
 so.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14832#comment:12>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler