December 2017
Beginner
372 pages
10h 32m
English
Content preview from TypeScript 2.x By Example
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Promises
Callbacks are good, they solve our problem of writing asynchronous code. But, as you may have noticed in the preceding code examples, callbacks are very verbose and have one too many handshakes. Additionally, if you want to write multiple callbacks wherein the response of one async operation triggers another async operation, we would have a very complex looking code with callbacks chaining to other callbacks.
To solve these problems we have promises. The promises are now part of native JavaScript since ES2015, so if we write a TypeScript code with promises, we would want to set our target compilation to ES2015 in tsConfig.json.
So, what are promises? A promise is an object which is returned by the asynchronous call and which represents ...
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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.
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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.