// 22.1.3.31 Array.prototype[@@unscopables] var UNSCOPABLES = require('./_wks')('unscopables'); var ArrayProto = Array.prototype; if (ArrayProto[UNSCOPABLES] == undefined) require('./_hide')(ArrayProto, UNSCOPABLES, {}); module.exports = function (key) { ArrayProto[UNSCOPABLES][key] = true; };