Plugin for String.format in javascript

//Helper functions

(function () {

    String.format = function () {

        // The string containing the format items (e.g. "{0}")

        // will and always has to be the first argument.

        var theString = arguments[0];

        // start with the second argument (i = 1)

        for (var i = 1; i < arguments.length; i++) {

            // "gm" = RegEx options for Global search (more than one instance)

            // and for Multiline search

            var regEx = new RegExp("\\{" + (i - 1) + "\\}", "gm");

            theString = theString.replace(regEx, arguments[i]);

        }

        return theString;

    }

})();