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JavaScript

Posted by Ajinkya Borade
Ajinkya Borade
Courses Plus Student 16,635 Points

JavaScript function addes value to itself as a variable !

I need to understand below function.

var guid = function() {

      var nav = window.navigator;
      var screen = window.screen;
      var guid = nav.mimeTypes.length;
      guid += nav.userAgent.replace(/\D+/g, '');
      guid += nav.plugins.length;
      guid += screen.height || '';
      guid += screen.width || '';
      guid += screen.pixelDepth || '';

      return guid;
  };

What is the line guid += ? How can function add to itself as a variable ?

1 Answer

Chris Shaw
Chris Shaw
26,650 Points
Chris Shaw
Chris Shaw
26,650 Points

Hi Ajinkya,

The value isn't been assigned to the function as that is impossible, the guid function has a locally scoped variable called guid which new values are been appended to.

Neal Gist
Neal Gist
8,438 Points

Ajinkya, if you pull up your browser's console and check this out: http://jsfiddle.net/vztmLL4h/ ; You'll see that guid is undefined from within the function's local scope, exactly as Chris has explained.

Ajinkya Borade
Ajinkya Borade
Courses Plus Student 16,635 Points

oh my mistake. thanks for spotting :)