[GHC] #3306: Improve syntax for GADT + records

[GHC]

#3306: Improve syntax for GADT + records
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    Reporter:  simonpj           |        Owner:                  
        Type:  feature request   |       Status:  new             
    Priority:  normal            |    Milestone:  6.12.1          
   Component:  Compiler          |      Version:  6.10.2          
    Severity:  normal            |   Resolution:                  
    Keywords:                    |   Difficulty:  Unknown         
    Testcase:                    |           Os:  Unknown/Multiple
Architecture:  Unknown/Multiple  |  
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Comment (by chak):

 I recently needed class constraints in a GADT with record syntax and used
 (B) with the HEAD.  So, there is definitely a need for this.

 I definitely prefer (B) out of the two choices listed above.  I think it
 is ok to make a breaking change here.  After all, this is very
 experimental territory still.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3306#comment:5>
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