[GHC] #15785: Improve/complete the GHCi :doc command

[GHC]

#15785: Improve/complete the GHCi :doc command
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           Reporter:  sjakobi        |             Owner:  (none)
               Type:  feature        |            Status:  new
  request                            |
           Priority:  normal         |         Milestone:
          Component:  GHCi           |           Version:  8.6.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 The `:doc` command, so far implemented as a ''tech preview'', could be a
 lot nicer:

 * For a type constructor, it should also show the data constructors and
 their documentation
 * It should include documentation on function arguments.
 * For records it should include any docs on the fields.

 Overall I think it should work roughly like the `:info` command, but of
 course enhanced by the docstrings.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15785>
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