Github user dkuppitz commented on a diff in the pull request:
https://github.com/apache/tinkerpop/pull/876#discussion_r202114064
--- Diff:
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_LP_NL_O_P_S_SE_SL_Traverser.java
---
@@ -0,0 +1,156 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.tinkerpop.gremlin.process.traversal.traverser;
+
+import org.apache.commons.collections.map.ReferenceMap;
+import org.apache.tinkerpop.gremlin.process.traversal.Step;
+import
org.apache.tinkerpop.gremlin.process.traversal.traverser.util.LabelledCounter;
+
+
+import java.util.Iterator;
+import java.util.Stack;
+
+public class B_LP_NL_O_P_S_SE_SL_Traverser<T> extends
B_LP_O_P_S_SE_SL_Traverser<T> {
+
+ protected Stack<LabelledCounter> nestedLoops;
+ protected ReferenceMap loopNames = null;
--- End diff --
Just asking for a comment here: Why can this not be a simple
`HashMap<String, LabelledCounter>`? This would save you the class casting later
on and you wouldn't have to register a new class for the Gryo serializer.
---
