Function Argument(1)

Code
function max() {
                var m = Number.NEGATIVE_INFINITY;
                for (var i = 0; i < arguments.length; i++) {
                    if (arguments[i] > m) m = arguments[i];
                }return m;
            }
            var largest = max(10, 20, 30);
            document.write(largest);

<script language = "javascript" type = "text/javascript">
            function Copy(a, p) {
                if (!a) a = [];
                //a = a||[];
                for (var prop in p) {
                    a.push(prop);
                }
                return a;
            }
            var o = { name: "Zhuobin", sex: "Male" };
            var a = Copy(a, o);
            document.write(a[0]);
            function f(x, y, z) {
                if (arguments.length != 3) {
                    throw new Error("Argument error!!");
                }
            } 
        </script>