rem: return this.select(function(value) { return value != undefined || value != null; 
add: return this.map(function(value, index) { return iterator(collections.pluck(index)); 
context:     return this.select(function(value) {      return value != undefined || value != null;    });
meta: 2320	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/2320/19200c26046dc00f15305e03b7c1d28b4c38c952/prototype.js/clean/web/scripts/prototype.js