Morgan - Simplifying JavaScript

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To Bob and Eric for giving me a foundation

Ever get the feeling youve woken up and everythings different? If youvelooked at modern JavaScript, you may feel like you woke up in a new worldwhere nothings the same.

Yesterday, you were tweaking a simple jQuery accordion. Today, you look atsome JavaScript code and the ubiquitous jQuery $ operator is gone. In itsplace are lots of strange dots ( ... ) and strange symbols ( => ) (the spreadoperator and arrow functions, as youll soon learn). Sure, some things lookfamiliar, such as class , but even that seems to be unpredictable (where are theprivate methods?).

Are you perplexed? Maybe a little excited? Well, I have good news for you:Everything has changed for the better.

When the ECMAScript 6 spec was releasedES6 for shortJavaScriptcode changed dramatically. The changes were so substantial that after readingthis book youll be able to tell at a glance which code was written withpre-ES6 syntax and which code was written with post-ES6 syntax. JavaScript nowis different. Modern JavaScript is any code composed with post-ES6 syntax.

Modern JavaScript is a pleasure to write. Im a long-time unrepentantJavaScript fan, but Ill admit that I found the old syntax a little clunky attimes, and it was pretty hard to defend. Modern JavaScript is better. But itschanged significantly, and catching up can be hard.

In this book, youll learn to write modern JavaScript from the ground up. ButIm not going to throw a bunch of syntax at you. I want you to learn to thinkin terms of contemporary JavaScript. Youll see every piece of syntaxwith a recommendation for not just how to use it, but when to use it.

Also, Im not going to run through every minor syntax change. I know your timeis valuable, so Ill only show you syntax that has high impact and thatssomething youll use over and over again. You can deal with edge cases whenthey arise. This book will give you the best features and nothing else.