jQuery title case headings

toTitleCase.js

(function ($) {
  'use strict';

  /**
   * To Title Case 2.1 – http://individed.com/code/to-title-case/
   * Copyright © 2008–2013 David Gouch. Licensed under the MIT License.
   *
   * @returns {string}
   */
  String.prototype.toTitleCase = function () {
    var smallWords = /^(a|an|and|as|at|but|by|en|for|if|in|nor|of|on|or|per|the|to|vs?\.?|via)$/i;

    return this.replace(/[A-Za-z0-9\u00C0-\u00FF]+[^\s-]*/g, function (match, index, title) {
      if (index > 0 && index + match.length !== title.length &&
        match.search(smallWords) > -1 && title.charAt(index - 2) !== ':' &&
        (title.charAt(index + match.length) !== '-' || title.charAt(index - 1) === '-') &&
        title.charAt(index - 1).search(/[^\s-]/) < 0) {
        return match.toLowerCase();
      }

      if (match.substr(1).search(/[A-Z]|\../) > -1) {
        return match;
      }

      return match.charAt(0).toUpperCase() + match.substr(1);
    });
  };

  $('h1, h1 > em, h2, h2 > em, h3, h3 > em, h4, h4 > em, h5, h5 > em').each(function () {
    
    var heading_string = $(this).html().toString();
    
    var heading_case = heading_string.toTitleCase();
    
    $(this).html(heading_case);
  });

}(jQuery));