// getting tag from 19.1.3.6 Object.prototype.toString() var cof = require('./_cof') , TAG = require('./_wks')('toStringTag') // ES3 wrong here , ARG = cof(function(){ return arguments; }()) == 'Arguments'; // fallback for IE11 Script Access Denied error var tryGet = function(it, key){ try { return it[key]; } catch(e){ /* empty */ } }; module.exports = function(it){ var O, T, B; return it === undefined ? 'Undefined' : it === null ? 'Null' // @@toStringTag case : typeof (T = tryGet(O = Object(it), TAG)) == 'string' ? T // builtinTag case : ARG ? cof(O) // ES3 arguments fallback : (B = cof(O)) == 'Object' && typeof O.callee == 'function' ? 'Arguments' : B; };