[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:  patch
        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 goldfire):

 I'm a little confused by the output generated in your gist. Is the `t`
 option assumed now? You don't seem to set it, but you do unset it. And, I
 think the output should be more explicit about that it's changing behavior
 based on the lack of a Show instance. Having the output sometimes be a
 value and sometimes be a type is confusing!

 In another direction, should we maybe promote the use of `:force`? This
 allows us to see the value of certain structures that don't have a `Show`
 instance.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3452#comment:12>
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