/*
 * @(#)$Id: ChoiceExp.java,v 1.8 2003/12/12 21:36:38 kohsuke Exp $
 *
 * Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the proprietary information of Sun Microsystems, Inc.  
 * Use is subject to license terms.
 * 
 */
package com.sun.msv.grammar;

/**
 * A|B.
 * 
 * @author <a href="mailto:kohsuke.kawaguchi@eng.sun.com">Kohsuke KAWAGUCHI</a>
 */
public final class ChoiceExp extends BinaryExp {
    
    ChoiceExp( Expression left, Expression right ) {
        super(left,right);
    }
    
    public Object visit( ExpressionVisitor visitor )                { return visitor.onChoice(this); }
    public Expression visit( ExpressionVisitorExpression visitor )    { return visitor.onChoice(this); }
    public boolean visit( ExpressionVisitorBoolean visitor )        { return visitor.onChoice(this); }
    public void visit( ExpressionVisitorVoid visitor )                { visitor.onChoice(this); }

    protected boolean calcEpsilonReducibility() {
        return exp1.isEpsilonReducible() || exp2.isEpsilonReducible();
    }

    // serialization support
    private static final long serialVersionUID = 1;    
}
