[GHC] #7658: Support empty record update syntax

[GHC]

#7658: Support empty record update syntax
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Reporter:  glguy             |          Owner:                  
    Type:  feature request   |         Status:  new             
Priority:  normal            |      Component:  Compiler        
 Version:  7.6.2             |       Keywords:                  
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
 Failure:  None/Unknown      |      Blockedby:                  
Blocking:                    |        Related:                  
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Comment(by monoidal):

 Shameless plug: Personally I like to allow changing phantom type
 parameters with the same mechanism as newtype coercions, described
 [http://hackage.haskell.org/trac/ghc/wiki/NewtypeWrappers here] and
 [http://markmail.org/message/ty2xrzenuyyap6wj#query:+page:1+mid:ty2xrzenuyyap6wj+state:results
 here].

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Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7658#comment:2>
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