February 2018
Intermediate to advanced
298 pages
8h 22m
English
Content preview from Learn ECMAScript - Second Edition
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Proxy traps
There are different traps for the different operations that can be performed on an object. Some of the traps need to return values. There are some rules you need to follow when returning values. The returned values are intercepted by the proxy to filter and/or check if the returned values obey the rules. If a trap doesn't obey rules while returning a value, then the proxy throws the TypeError exception.
The value of this inside a trap is always a reference to the handler.
Let's take a look at the various kinds of traps.
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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.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.