rem: return this; 
add: return String(this); 
context:   scan: function(pattern, iterator) {    this.gsub(pattern, iterator);    return this;  },
meta: 9100	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/9100/2d4247a14ff4ce25ad80cbc65b787dfde7ddb16e/prototype.js/buggy/typo3/contrib/prototype/prototype.js