Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : master
http://hackage.haskell.org/trac/ghc/changeset/4baebfae0254e4cd9d960c3c926ab8d005eddfc3 >--------------------------------------------------------------- commit 4baebfae0254e4cd9d960c3c926ab8d005eddfc3 Author: Simon Peyton Jones <simo...@microsoft.com> Date: Wed Oct 31 08:54:33 2012 +0000 Comments only >--------------------------------------------------------------- compiler/simplCore/OccurAnal.lhs | 13 ++++++++----- 1 files changed, 8 insertions(+), 5 deletions(-) diff --git a/compiler/simplCore/OccurAnal.lhs b/compiler/simplCore/OccurAnal.lhs index d75a224..ac8b2f3 100644 --- a/compiler/simplCore/OccurAnal.lhs +++ b/compiler/simplCore/OccurAnal.lhs @@ -1697,11 +1697,14 @@ Note [getProxies is subtle] ~~~~~~~~~~~~~~~~~~~~~~~~~~~ The code for getProxies isn't all that obvious. Consider - case v |> cov of x { DEFAULT -> - case x |> cox1 of y { DEFAULT -> - case x |> cox2 of z { DEFAULT -> r + case v |> cov of x { DEFAULT -> {{ let v = x |> sym cov }} + case x |> cox1 of y { DEFAULT -> {{ let x = y |> sym cox1 }} + case x |> cox2 of z { DEFAULT -> {{ let x = z |> sym cox2 }} + r -These will give us a ProxyEnv looking like: +Bindings in double braces are injected. + +At 'r', these will give us a ProxyEnv looking like: x |-> (x, [(y, cox1), (z, cox2)]) v |-> (v, [(x, cov)]) @@ -1711,7 +1714,7 @@ From this we want to extract the bindings y = x |> cox1 Notice that later bindings may mention earlier ones, and that -we need to go "both ways". +we can go "both ways". Note [Zap case binders in proxy bindings] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
