[GHC] #14963: ghci -fdefer-type-errors can't run IO action from another module

[GHC]

#14963: ghci -fdefer-type-errors can't run IO action from another module
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        Reporter:  elaforge          |                Owner:  tdammers
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.4.2
       Component:  GHCi              |              Version:  8.4.1
      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 tdammers):

 Replying to [comment:16 simonpj]:
 > As a short term fix how bad would it be to make `-fdefer-type-errors`
 incompatible with GHCi?
 >
 > We could apply that fix to HEAD (until we fix this ticket properly) and
 perhaps even to 8.4.3.

 I wouldn't be surprised to find that this breaks someone's workflow. Maybe
 we could get some opinions on this from the community?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14963#comment:19>
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