[GHC] #14052: Significant GHCi speed regression with :module and `let` in GHC 8.2.1

[GHC]

#14052: Significant GHCi speed regression with :module and `let` in GHC 8.2.1
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        Reporter:  RyanGlScott       |                Owner:  osa1
            Type:  bug               |               Status:  closed
        Priority:  high              |            Milestone:  8.4.2
       Component:  GHCi              |              Version:  8.2.1-rc2
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11547            |  Differential Rev(s):  Phab:D4478
       Wiki Page:                    |
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Comment (by sighingnow):

 Revert Phab:D2447 made the ticket:11547 existed in HEAD again. See also
 ticket:14996#comment:2.

 Perhaps we should implement the conclusion posted in comment:10 ? If so,
 I'm volunteer to give that a try.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14052#comment:24>
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