-        var doc = getDocumentFromXML('<section><a></a><b></b></section>'),
-            a = doc.root.contents()[0],
-            b = doc.root.contents()[1],
-            c = canvas.fromXMLDocument(doc);
+        var doc = getDocumentFromXML('<section><c></c><a></a><b></b></section>'),
+            c = doc.root.contents()[0],
+            a = doc.root.contents()[1],
+            b = doc.root.contents()[2],
+            cv = canvas.fromXMLDocument(doc);
+
+        a.document.transaction(function() {
+            a.before(b); // => cab
+            b.after(c); // => bca
+        }, {
+            error: function(e) {throw e;}
+        });