javascript set max length of string

1String.prototype.trimEllip = function (length) {
2  return this.length > length ? this.substring(0, length) + "..." : this;
3}

1(function() {
2    strings = ["z"];
3    try {
4        while(true) {
5            strings.push(strings[strings.length - 1] + strings[strings.length - 1]);
6        }
7    } catch(err) {
8        var k = strings.length - 2;
9        while(k >= 0) {
10            try {
11                strings.push(strings[strings.length - 1] + strings[k]);
12                k--;
13            } catch(err) {}
14        }
15        console.log("The maximum string length is " + strings[strings.length - 1].length);
16    }
17})();