[GHC] #13697: Teach GHCi to deduplicate history

[GHC]

#13697: Teach GHCi to deduplicate history
-------------------------------------+-------------------------------------
        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:                    |
-------------------------------------+-------------------------------------

Comment (by goldfire):

 I'm very confused. The following is on a Linux machine:

 {{{
 12:22:05 at powerpuff ~> echo $0
 -bash
 12:22:27 at powerpuff ~> echo "hello"
 hello
 12:22:33 at powerpuff ~> echo "hello"
 hello
 12:22:35 at powerpuff ~> history | tail -n 4
   510  echo $0
   511  echo "hello"
   512  echo "hello"
   513  history | tail -n 4
 12:22:41 at powerpuff ~>
 }}}

 I have no recollection of ever considering this issue, so I don't believe
 I've set a configuration somewhere to change it. (And I looked at my
 `.bashrc` and see nothing working in this direction.)

 It's not that I'm opposed to the feature as proposed, exactly, but I feel
 like I'm missing some small superpower that the rest of you share...

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13697#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler