[GHC] #14691: Replace EvTerm with CoreExpr

[GHC]

#14691: Replace EvTerm with CoreExpr
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        Reporter:  nomeata           |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.3
  checker)                           |
      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 simonpj):

 >  I cannot use Core’s Cast for that, because the EvTerm may be a
 EvTypeable.

 I think you can.  `getEvTerm` calls `ctEvTerm` which always returns either
 an `EvId` (which we can do in Core) or an `EvCoercion` (ditto).  Aside
 from coercions (alas) all evidence is represented just by an Id.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14691#comment:24>
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