[GHC] #2595: Implement record update for existential and GADT data types

[GHC]

#2595: Implement record update for existential and GADT data types
------------------------------+---------------------------------------------
 Reporter:  simonpj           |          Owner:                  
     Type:  feature request   |         Status:  closed          
 Priority:  normal            |      Milestone:  6.12 branch     
Component:  Compiler          |        Version:  6.8.3           
 Severity:  normal            |     Resolution:  fixed           
 Keywords:                    |     Difficulty:  Unknown         
 Testcase:  tc244             |   Architecture:  Unknown/Multiple
       Os:  Unknown/Multiple  |  
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Changes (by simonpj):

  * testcase:  => tc244
  * status:  new => closed
  * resolution:  => fixed

Comment:

 OK I have mostly-implemented this feature request
 {{{
 Tue Oct 28 11:54:27 GMT Standard Time 2008  simonpj at microsoft.com
   * Mostly-fix Trac #2595: updates for existentials

   Ganesh wanted to update records that involve existentials.  That
   seems reasonable to me, and this patch covers existentials, GADTs,
   and data type families.

   The restriction is that
     The types of the updated fields may mention only the
     universally-quantified type variables of the data constructor

   This doesn't allow everything in #2595 (it allows 'g' but not 'f' in
   the ticket), but it gets a lot closer.
 }}}
 No need to merge.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2595#comment:3>
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