add: return this; 
context:   each: function(iterator) {    var index = 0;    try {      this._each(function(value) {        try {          iterator(value, index++);        } catch (e) {          if (e != $continue) throw e;        }      });    } catch (e) {      if (e != $break) throw e;    }  },
meta: 2801	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/2801/7e143d2df37946a5416f0f043869478087652eb6/prototype.js/clean/examples/testcases/prototype.js