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diff --git a/src/jdk/nashorn/internal/ir/Expression.java b/src/jdk/nashorn/internal/ir/Expression.java
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+/*
+ * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.nashorn.internal.ir;
+
+import jdk.nashorn.internal.codegen.types.Type;
+
+/**
+ * Common superclass for all expression nodes. Expression nodes can have
+ * an associated symbol as well as a type.
+ *
+ */
+public abstract class Expression extends Node {
+    private Symbol symbol;
+
+    Expression(long token, int start, int finish) {
+        super(token, start, finish);
+    }
+
+    Expression(long token, int finish) {
+        super(token, finish);
+    }
+
+    Expression(Expression expr) {
+        super(expr);
+        this.symbol = expr.symbol;
+    }
+
+    /**
+     * Return the Symbol the compiler has assigned to this Node. The symbol
+     * is the place where it's expression value is stored after evaluation
+     *
+     * @return the symbol
+     */
+    public Symbol getSymbol() {
+        return symbol;
+    }
+
+    /**
+     * Assign a symbol to this node. See {@link Expression#getSymbol()} for explanation
+     * of what a symbol is
+     *
+     * @param lc lexical context
+     * @param symbol the symbol
+     * @return new node
+     */
+    public Expression setSymbol(final LexicalContext lc, final Symbol symbol) {
+        if (this.symbol == symbol) {
+            return this;
+        }
+        final Expression newExpr = (Expression)clone();
+        newExpr.symbol = symbol;
+        return newExpr;
+    }
+
+    /**
+     * Check if the expression has a type. The default behavior is to go into the symbol
+     * and check the symbol type, but there may be overrides, for example in
+     * getters that require a different type than the internal representation
+     *
+     * @return true if a type exists
+     */
+    public boolean hasType() {
+        return getSymbol() != null;
+    }
+
+    /**
+     * Returns the type of the expression. Typically this is the symbol type. No types
+     * are stored in the expression itself, unless it implements TypeOverride.
+     *
+     * @return the type of the node.
+     */
+    public Type getType() {
+        assert hasType() : this + " has no type";
+        return symbol.getSymbolType();
+    }
+}