patch applied (ghc): More refactoring of constraint simplification

[Simon Peyton Jones]

Mon Dec 11 08:07:32 PST 2006  simonpj at microsoft.com
  * More refactoring of constraint simplification
  
  This patch fixes several bugs in the handling of impliciation
  constraints, thereby fixing several regression-suite failures.
  
  On the way I managed to further simplify the code in TcSimplify;
  the extra lines are comments.
  

    M ./compiler/typecheck/TcBinds.lhs -15 +15
    M ./compiler/typecheck/TcMType.lhs -4 +12
    M ./compiler/typecheck/TcRnTypes.lhs -1 +6
    M ./compiler/typecheck/TcRules.lhs -2 +2
    M ./compiler/typecheck/TcSimplify.lhs -128 +155
    M ./compiler/typecheck/TcType.lhs -3 +8