[GHC] #4832: Inconsistent import of instances in GHCi

[GHC]

#4832: Inconsistent import of instances in GHCi
---------------------------+------------------------------------------------
  Reporter:  sebf          |          Owner:                  
      Type:  bug           |         Status:  closed          
  Priority:  high          |      Milestone:  7.4.1           
 Component:  GHCi          |        Version:  7.0.1           
Resolution:  fixed         |       Keywords:                  
  Testcase:                |      Blockedby:                  
Difficulty:                |             Os:  Unknown/Multiple
  Blocking:                |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown  |  
---------------------------+------------------------------------------------
Changes (by batterseapower):

  * status:  new => closed
  * resolution:  => fixed


Comment:

 Quite annoying to track down, but it is now fixed and pushed:

 {{{
 commit 3deca8f44135bd1a146902f498189af00dd4d7b4
 Author: Max Bolingbroke <batterseapower at hotmail.com>
 Date:   Sun Apr 3 16:50:47 2011 +0100

     Use tcRnImports rather than rnImports with GHCi "import" statement:
 fixes #4

     The bug here was that just using rnImports does not ensure that any
 dependen
     orphan modules are loaded, so instances declared by such modules will
 not be
     usable from the GHCi command line after an "import".

     This did not affect the :m syntax because it takes a different code
 path and
     uses getModuleExports directly, which contains its own calls to the
 orphan-m
     loading stuff.
 }}}

 I added a test as well.

 I think that mkExportEnv, hscGetModuleExports, getModuleExports,
 tcGetModuleExports could probably be deleted by just making the :m
 codepath a special case of the "import" codepath (in
 InteractiveEval.setContext), but I'm not familiar enough with the code to
 be confident about making that change.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4832#comment:3>
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