[GHC] #3452: Show type of most recent expression in GHCi

[GHC]

#3452: Show type of most recent expression in GHCi
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        Reporter:  ozy               |            Owner:
            Type:  feature request   |           Status:  new
        Priority:  lowest            |        Milestone:  7.6.2
       Component:  GHCi              |          Version:  6.10.4
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by osa1):

 I'm a new contributor(preparing my first patch) and I'm working on this,
 currently my patch is this:
 https://github.com/osa1/ghc/commit/d542b418d913b4aba04e497fb63b70108b058f48

 This is probably far from being finished, I'm looking for reviews/comments
 on this. I'm not very happy with the way it is implemented but for now
 this is only way I could think.

 If someone point me a batter way to do I'll happily change my patch.

 Here's an example output: https://gist.github.com/osa1/6201852

 One thing I didn't like about this output is the _it_ part, to me it's not
 user friendly enough. I think we need to tell user that his value isn't
 showable so only it's type is shown.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3452#comment:10>
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