# File kwartz.rb, line 3223
        def parse_compare
            expr = parse_arith()
            case t = token()
            when '==', '!=', '>', '>=', '<', '<=', '.>', '.>=', '.<', '.<=', '.==', '.!='
                scan()
                if token() == :empty && (t == '==' || t == '!=')
                    scan()
                    t2 = t == '==' ? :empty : :notempty
                    expr = ExprNode.new(t2, expr, nil)
                else
                    expr2 = parse_arith()
                    expr = ExprNode.new(t, expr, expr2)
                end
            end
            return expr
        end