and found an error in the sixth edition of the JavaScript definitive guide

PDF version, English version 158th page,

var IsArray = Function.isarray | | Function (o) {return typeof o = = = = "Object" &&object.prototype.tostring.call (o) = = = "[Object Array]";}; return typeof o = = = "Object" &&object.prototype.tostring.call (o) = = = "[Object Array]";};

Array.isarray is a function provided by ES5, this example is to implement this function in ES3, first, if the browser supports Array.isarray, it is assigned to IsArray, otherwise the subsequent function is assigned to IsArray. Therefore, the correct one should be:

var IsArray = Array.isarray | | Function (o) {return typeof o = = = "Object" && Object.prototype.toString.call (o) = = = "[Object Array]";};

and found an error in the sixth edition of the JavaScript definitive guide