February 2018
Intermediate to advanced
298 pages
8h 22m
English
Content preview from Learn ECMAScript - Second Edition
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The document.cookie is a strange object
As you saw earlier, document.cookie shows a special behavior. Instead of replacing all cookies, it updates the variable to the new cookie. This behavior is implemented by a document that is actually called a host object instead of a native object. Host objects have the power to do anything, as they don't need to follow the semantics for regular objects.
Host objects are actually the objects provided in a particular environment--in our case, the browser. When JavaScript runs on the server (Node.js), you do not have access to a document or window. That means they're host objects--that is, dependent on hosts and implemented by hosts (browsers).
In this case, document.cookie overrides the assignment operator ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
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