Merge pull request #24 from derbyjs/fix-deferred-destroy

Fix deferred destroy

Author: craigbeck

lib/templates.js

@@ -633,11 +633,16 @@ AsProperty.prototype.emit = function(context, target) {
   this.addListeners(target, node, this.lastSegment);
 };
 AsProperty.prototype.addListeners = function(target, object, key) {
-  var deleteProperty = function () {
-    delete object[key];
-  }
   this.addDestroyListener(target, function asPropertyDestroy() {
-    process.nextTick(deleteProperty);
+    // memoize initial reference so we dont destroy
+    // property that has been replaced with a different reference
+    var intialRef = object[key];
+    process.nextTick(function deleteProperty() {
+      if (intialRef !== object[key]) {
+        return;
+      }
+      delete object[key];
+    });
   });
 };
 AsProperty.prototype.addDestroyListener = elementAddDestroyListener;