trash = expr.accept(this); return self;
JExpression newExpr = (JExpression)expr.accept(this); return new JUnaryMinusExpression(null, newExpr);
    public Object visitUnaryMinusExpression(JUnaryExpression self,                                          JExpression expr)    {        blockStart("UnaryMinusExpression");        trash = expr.accept(this);	return self;    }