/**
 * Insert the type's description here.
 * Creation date: (3/3/2003 2:22:01 AM)
 * @author: Administrator
 */
public class Expr {
	private int value;
	private String id;
	private Expr left;
	private Expr right;
	private String op;
/**
 * Expr constructor comment.
 */
public Expr() {
	super();
}
	public Expr(Expr l, Expr r, String o){
		left=l; right=r; op=o;
	}
	public Expr(Integer i){ value=i.intValue();
	}
	public Expr(String i){ id=i;}
public String toXML() {
	String result = "<Expr>";
	result += (left == null)
		? ((id==null)? "<value>" + value + "</value>" : id)
		: "<value>"
			+ value
			+ "</value>"
			+ "<op>"
			+ "</op>"
			+ left.toXML()
			+ right.toXML(); 
	result += "</Expr>";
	return result;
}
}