From e3dd6b24ff41593bd46a6c29104d7972768c6a1b Mon Sep 17 00:00:00 2001
From: tcurtis <tyler.l.curtis@gmail.com>
Date: Wed, 4 Aug 2010 16:32:20 -0500
Subject: [PATCH] Fix deletion of nodes in .transform.

---
 src/Tree/Pattern/Transformer.nqp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Tree/Pattern/Transformer.nqp b/src/Tree/Pattern/Transformer.nqp
index a790b22..9b7c525 100644
--- a/src/Tree/Pattern/Transformer.nqp
+++ b/src/Tree/Pattern/Transformer.nqp
@@ -119,7 +119,7 @@ module Tree::Walker {
             $shouldDescend := !$walker.descend_until.ACCEPTS($node);
         }
 
-        if ($shouldDescend) {
+        if ($shouldDescend && !pir::isnull__IP($result)) {
             $walker.depth($walker.depth + 1);
             my $newChildren := walkChildren($walker, $result);
             replaceChildren($result, $newChildren);