es6-features.org

ECMAScript 6: Feature Overview & Comparison

Copyright (c) 2015 Ralf S. Engelschall <[email protected]> <@engelschall>
Partially based on code snippets by Luke Hoban.
Licensed under MIT license.

This is the source of the website es6-features.org, a small overview of ECMAScript 6 language features and a comparison to the older/traditional ECMAScript 5 equivalents.

Frequently Asked Questions? (FAQ)

• Why was it setup? Is the ECMAScript 6 draft not enough?

  It was setup by computer scientist and software architect Ralf S. Engelschall in March 2015 in order to promote ECMAScript 6 in the software engineering projects around him and to have bookmarkable URLs at hand for referencing certain ECMAScript 6 features.

• Where can I find the current browser support status quo for ECMASCript 6?

  Have a look at the regularily updated ECMAScript compatibility table by kangax. There, especially notice the column "Babel + core-js" as this is what can be achieved today with transpiling (and that's fully sufficient for practice).

• Where can I find the latest ECMAScript 6 standard?

  The final ECMAScript 6 standard is still not published. But you can find the latest drafts on ecmascript.org.

• How can I use ECMAScript 6 if my JavaScript runtime still does not support it?

  Use the awesome Babel transpiler. For Node.js/io.js environments just use its tricky require hook. For browser environments use Babel in conjunction with Browserify and its Babelify plugin. For other tools see Using Babel. If you want to see pre-integrated scenarios, check out our sibling project es6-support for various code examples!

• Why uses the website for ECMAScript 6 the "reduced" syntactic sugar style without semicolons as the default, but for ECMAScript 5 the "traditional" syntactic sugar style with semicolons?

  ECMAScript since its earliest days supported automatic semicolon inference/insertion, of course. But people coding ECMAScript 5 started it in an era where lots of tools (especially source code compressors) had problems when simicolons where left out from the source code. As a consequence, most ECMAScript 5 coders sticked to the traditional coding style with semicolons as the syntactic sugar, although in most of the cases they are not necessary. But this era is gone today. Both ECMAScript 6 and all tools (including compressors) perfectly support automatic semicolon inference/insertion nowadays. As a consequence, ECMAScript 6 coders nowadays finally can nearly get rid of all semicolons and this way clutter their source code a lot less with bare syntactic sugar. Ralf S. Engelschall is a strong promoter of reducing source code to its bare minimum. Hence, in his personal opinion ECMAScript 6 should be coded with as less syntactic sugar as possible and hence without semicolons. But if you disagree, just switch the shown style on the website. If you even need to enforce a particular style for both ES6 and ES5 code snippets in your bookmarks, just use one of the following URLs: ES6-Features (reduced style) or ES6-Features (traditional style)

• I still don't understand: why should I use ECMAScript 6? ECMAScript 5 looks sufficient.

  ECMAScript 5 is a nice and decent programming language, of course. But because of its history, it has some nasty aspects which ECMAScript 6 finally resolves. As programming never is just about getting the necessary functionality done, it is advised to also use the best language, too. ECMAScript 6's language design is cleaner than ECMAScript 5, its syntax increases the expressiveness of your code, it decreases the necessary boilerplate code (e.g. function vs. arrow syntax) and it especially let you get rid of some very nasty but required hacks and workarounds from the ECMAScript 5 era (e.g. var self = this). So, ECMAScript 5 might be sufficient, but ECMAScript 6 nevertheless is an important improvement.

• I've found a mistake, how can I contribute?

  The source is the file features.txt, everything else on es6-features.org is just generated out of it. Fork this project on Github, edit the file features.txt and then please send a pull request.