[GHC] #13697: Teach GHCi to deduplicate history

[GHC]

#13697: Teach GHCi to deduplicate history
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        Reporter:  bgamari           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.0.1
      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 bgamari):

 > so there is no duplication of everything.  I believe the OP asks for the
 former (and I support this.)

 Exactly; I should have been more clear about this.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13697#comment:5>
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