// $Id: ExprConstant.java,v 1.2 2002/09/04 18:06:01 leavens Exp leavens $
// Com S 362 homework

/** Expressions that are constants, like 3. */
public class ExprConstant extends ExprNegation {

    private double val;

    /** Initialize this expression tree. */
    public ExprConstant(double val) {
        super(null);
        this.val = val;
    }

    /** Return the value of this expression. */
    public double value() {
        return val;
    }

    /** Constants don't support isLessThan. */
    public boolean isLessThan() {
        throw new UnsupportedOperationException();
    }
}