[DISCUSSIONS] Should we replace CoffeeScript with ES6?

[engelgabriel]

Universal JavaScript: Adopting ECMAScript 2015 (aka ES6)

SOURCE: http://info.meteor.com/blog/whats-coming-in-meteor-12-and-beyond

ECMAScript 2015, also known as ES6, is going to be huge for the JavaScript community and for JavaScript adoption. The new version of the language is "the best JavaScript we've ever had," with classes, block scoping, and many other additions. We're excited that it will bring many new developers to JavaScript by addressing the objections that developers from other backgrounds sometimes raise.

We think anyone writing an app in JavaScript should be using ES2015. So we are making ES2015 the official JavaScript of the Meteor platform. Our goal is to make Meteor the best way to use ES2015, and to provide a seamless ES2015 experience across the whole platform and across the client and the server. Meteor 1.2 will be the first step in making that seamless development experience: we're adding support for all its features except for modules, automatically transpiling JS files with Babel so they work on all of Meteor's supported devices and browsers, and changing all our examples and documentation to ES2015.

We hope that you'll make the switch to ES2015 today, especially given how easy this new support makes it. It really is a huge improvement on JavaScript. But if you're not ready to switch, or want to transition your codebase gradually, you'll have that option. You can write some parts of your app in ES2015, some parts without, and adopt ES2015 at your own pace.

Special thanks to Ben Newman, Meteor core developer and Ecma TC39 standards committee member, for his leadership in this area.

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[engelgabriel]

https://robots.thoughtbot.com/replace-coffeescript-with-es6

[engelgabriel]

http://blog.ksol.fr/from-coffeescript-to-es2015

[engelgabriel]

https://forums.meteor.com/t/use-es2015-or-coffeescript/7815

[whitelynx]

👍 I'd likely be willing to contribute if the project was written in ES6 instead of CoffeeScript.

[geekgonecrazy]

@engelgabriel based on the articles you linked here along it seems they are pretty similar.

Initially I would have said es6 all the way. But after using coffeescript here. Its honestly not that bad. At some point it becomes just another language.

My question is are the people that bawk at coffeescript already familiar with es6 features that we would be using right out of the gate? Or do they just like it because it'd be javascript? Because if not either way there is a learning curve.

Note: not arguing against es6. I like it. But like I said. Its just another language. The addition of classes almost makes es6 a new language. :)

[Morgul]

I've got a bit of experience with setting up projects for ES6 (Babel.js is my current favorite transpiler), and I'm more than willing to start doing the conversion work once it gets the green light. We can do it in chunks (and someone more familiar with the project should probably decide what those chunks should be), and over time get the project on ES6. Then, Babel.js supports shutting off portions of the transpiling, as browsers get more compatible. (Additionally, the android/ios apps can keep some of them turned on, while the desktop shuts those off, since mobile moves at a slower pace than desktop browsers.)

[engelgabriel]

@Morgul you will find this link interesting: http://info.meteor.com/blog/whats-coming-in-meteor-12-and-beyond

[Morgul]

@geekgonecrazy I'm about 50/50 when it comes to knowing the new features. While I have some opinions about CoffeeScript's syntax (some of which are negative, I admit), to me that's less the point.

For web developers, it's not possible to avoid learning javascript, really. Most web guys will have to learn it. It's certainly where the mindshare is, and is likely to stay. So, as a web developer, if I want to contribute to this awesome chat application, should I have to learn a language I might not know (CoffeeScript), or a language I'm already using (JavaScript)?

Right now we're in the awkward transition phase where few people know ES6, but that's quickly changing. I'd rather see a project position itself to ease future contributions, rather than limit them, unless there's a good reason for it. Since ES6 gives most of the desired features of CoffeeScript... why shouldn't there be a change?

Or, let me put it another way: if you consider ES6 and CoffeeScript to be roughly equal, doesn't it make sense to choose the more popular?

[Morgul]

@engelgabriel Well then! It seems like the Meteor community's decided that ES6 is the best direction to go. (And they use babel! Sweet!)

[rodrigok]

We need to wait for Meteor 1.2 to be able to use ES6, and no, ES6 doesn't has all features that CoffeeScript has.

[geekgonecrazy]

@rodrigok I know its missing a good portion of the ruby style conditions. What else is es6 missing? Just out of curiousity

[rodrigok]

@geekgonecrazy

• Conditions and, or, is, isnt, not, in, etc instead && and ||, ===, etc...
• Parenthesis if a is b instead if (a == b)
• Code block with keys instead identation
• Loop over objects
• Loop with closures using do instead a lot of code
• A lot of features related with loops
• Existential operator if user?.name?.first is true instead if (user && user.name && user.name.first === true) or a ?= 1 instead if (a === undefined) a = 1

And some another features

[Morgul]

@rodrigok As for usage before 1.2, it seems there are a couple options, all with some trade offs: meteor/babel#3

On the surface it doesn't look like it would be that terrible to integrate, even before Meteor 1.2. But, it would definitely need a proof of concept project to see how it all played out.

Regarding CoffeeScript features vs ES6 features; of course you're right. They aren't a 1:1; I was taking @geekgonecrazy's premise of 'it's just another language' and running with it a bit.