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Ajinkya Borade
Courses Plus Student 16,635 PointsJavaScript 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
26,650 PointsHi 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
8,438 PointsNeal Gist
8,438 PointsAjinkya, 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
Courses Plus Student 16,635 PointsAjinkya Borade
Courses Plus Student 16,635 Pointsoh my mistake. thanks for spotting :)