patch applied (ghc-7.0/ghc): Beautiful new approach to the skolem-escape check and untouchable

[Ian Lynagh]

Fri Oct  8 06:37:51 PDT 2010  simonpj at microsoft.com
  * Beautiful new approach to the skolem-escape check and untouchable
  
  Instead of keeping a *set* of untouchable variables in each
  implication contraints, we keep a *range* of uniques for the
  *touchable* variables of an implication.  This are precisely
  the ones we would call the "existentials" if we were French.
  
  It turns out that the code is more efficient, and vastly easier
  to get right, than the set-based approach.
  
  Fixes Trac #4355 among others

    M ./compiler/ghci/RtClosureInspect.hs -2 +2
    M ./compiler/typecheck/TcBinds.lhs -2 +2
    M ./compiler/typecheck/TcMType.lhs -8 +8
    M ./compiler/typecheck/TcPat.lhs -4 +5
    M ./compiler/typecheck/TcRnDriver.lhs -5 +5
    M ./compiler/typecheck/TcRnMonad.lhs -13 +27
    M ./compiler/typecheck/TcRnTypes.lhs -4 +29
    M ./compiler/typecheck/TcRules.lhs -2 +2
    M ./compiler/typecheck/TcSMonad.lhs -19 +23
    M ./compiler/typecheck/TcSimplify.lhs -15 +14
    M ./compiler/typecheck/TcSplice.lhs -2 +2
    M ./compiler/typecheck/TcUnify.lhs -13 +11

View patch online:
http://darcs.haskell.org/cgi-bin/darcsweb.cgi?r=ghc-7.0/ghc;a=darcs_commitdiff;h=20101008133751-1287e-e235deb7a0e18b0354f3e83642a6c98ad5dc1bec.gz