[GHC] #3640: NamedFieldPuns broken in where clauses

[GHC]

#3640: NamedFieldPuns broken in where clauses
--------------------------------------------+-------------------------------
    Reporter:  cjs                          |        Owner:  igloo     
        Type:  merge                        |       Status:  new       
    Priority:  normal                       |    Milestone:            
   Component:  Compiler                     |      Version:  6.12.1 RC1
    Severity:  major                        |   Resolution:            
    Keywords:  NamedFieldPuns               |   Difficulty:  Unknown   
    Testcase:  rename/should_compile/T3640  |           Os:  Linux     
Architecture:  x86_64 (amd64)               |  
--------------------------------------------+-------------------------------
Changes (by simonpj):

  * testcase:  => rename/should_compile/T3640
  * owner:  simonpj => igloo
  * type:  bug => merge

Comment:

 Thank you for reporting this bug -- excellent catch.  Fixed by
 {{{
 Thu Nov  5 08:55:25 PST 2009  simonpj at microsoft.com
   * Fix Trac #3640, plus associated refactoring

   In fixing this bug (to do with record puns), I had the usual rush of
   blood to the head, and I did quite a bit of refactoring in the way
   that duplicate/shadowed names are reported.

   I think the result is shorter as well as clearer.

   In one place I found it convenient for the renamer to use the ErrCtxt
   carried in the monad.  (The renamer used not to have such a context,
   but years ago the typechecker and renamer monads became one, so now it
   does.)   So now it's availble if you want it in future.

     M ./compiler/rename/RnBinds.lhs -73 +50
     M ./compiler/rename/RnEnv.lhs -48 +45
     M ./compiler/rename/RnExpr.lhs -10 +9
     M ./compiler/rename/RnPat.lhs -3 +1
     M ./compiler/rename/RnSource.lhs -34 +29
     M ./compiler/rename/RnTypes.lhs -1 +1
     M ./compiler/typecheck/TcRnMonad.lhs -32 +47
 }}}
 Ian, please merge this if it goes over smoothly, which I think it will.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3640#comment:2>
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