javascript - Why do we use to detect type of object is function? -

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why use in javascript application this:

if ( typeof object.create !== 'function' ) {     object.create = function( obj ) {         function f() {};         f.prototype = obj;         return new f();     }; }

this called polyfill -- detects whether feature of javascript supported current users browser, , if it's not there, defines other scripts come page run on browser.


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