(function() {

  /* _ES5_COMPAT_START_ */
  if (!String.prototype.trim) {
    /**
     * Trims a string (removing whitespace from the beginning and the end)
     * @function external:String#trim
     * @see <a href="https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String/Trim">String#trim on MDN</a>
     */
    String.prototype.trim = function () {
      // this trim is not fully ES3 or ES5 compliant, but it should cover most cases for now
      return this.replace(/^[\s\xA0]+/, '').replace(/[\s\xA0]+$/, '');
    };
  }
  /* _ES5_COMPAT_END_ */

  /**
   * Camelizes a string
   * @memberOf fabric.util.string
   * @param {String} string String to camelize
   * @return {String} Camelized version of a string
   */
  function camelize(string) {
    return string.replace(/-+(.)?/g, function(match, character) {
      return character ? character.toUpperCase() : '';
    });
  }

  /**
   * Capitalizes a string
   * @memberOf fabric.util.string
   * @param {String} string String to capitalize
   * @param {Boolean} [firstLetterOnly] If true only first letter is capitalized
   * and other letters stay untouched, if false first letter is capitalized
   * and other letters are converted to lowercase.
   * @return {String} Capitalized version of a string
   */
  function capitalize(string, firstLetterOnly) {
    return string.charAt(0).toUpperCase() +
      (firstLetterOnly ? string.slice(1) : string.slice(1).toLowerCase());
  }

  /**
   * Escapes XML in a string
   * @memberOf fabric.util.string
   * @param {String} string String to escape
   * @return {String} Escaped version of a string
   */
  function escapeXml(string) {
    return string.replace(/&/g, '&amp;')
       .replace(/"/g, '&quot;')
       .replace(/'/g, '&apos;')
       .replace(/</g, '&lt;')
       .replace(/>/g, '&gt;');
  }

  /**
   * String utilities
   * @namespace fabric.util.string
   */
  fabric.util.string = {
    camelize: camelize,
    capitalize: capitalize,
    escapeXml: escapeXml
  };
})();
