Including but not limited to: Proper tail recursion (^_^) and destructuring.
Tracked at http://node.green
We don't have an ES2015 features page up to date yet, but it's going to be ready any day now (and we're going to link to node.green anyway most likely).
Also, the fate for tail-call-elimination is pretty uncertain at the moment; see: https://github.com/tc39/proposal-ptc-syntax
Note that ptc syntax _ensures_ tail calls, tail calls themselves have _already_ been approved in ES2015 and are live in V8 (under a flag), you can follow their status here: https://bugs.chromium.org/p/v8/issues/detail?id=4698
As far as I can see WebKit/Safari is the only major browser that has an implementation: https://kangax.github.io/compat-table/es6/#test-proper_tail_...
When last I checked, just having an unused `let` statement in a function made V8 bail out to the slow compiler, making ES2015 off-limits for anything nontrivial. But that was some months ago.
Any info on when it is going to come out of that corner?
5.1 has a preliminary support for WASM. You can enable it via the flag --expose_wasm in d8. Alternatively you can try out the WASM demos with Chrome 51 (Beta Channel)."
The future is coming fast.
Pouplar browsers get updated quite often. And those, which got updated rarely, became unpopular. Everything will be fine, I think :)
What this means is that web standards can move significantly faster than in the past. Interesting new technologies like WASM can be implemented and tested without waiting 5-6 years anymore. Very exciting to see as a web developer.
There's been some activity lately, but so far just looks like they're laying groundwork. Dunno where it is in the priority list. The last blocker was supposedly the finalization of the HTML5 module-loader spec, and that came out a couple weeks ago.
See https://groups.google.com/a/chromium.org/forum/#!searchin/bl... for more information.
I'm wondering about the performance cost of these new features (hopefully zero).
It is very sad that people working on es spec do not care enough about performance
If you ask MDN: Was initially in the ECMAScript 6 draft, but got removed in revision 27 (August 2014). Please see older revisions of ES 6 for specification semantics.
Non-standard. Do not use! The array comprehensions is non-standard, and it's unlikely to be added to ECMAScript. For future-facing usages, consider using Array.prototype.map, Array.prototype.filter, and arrow functions.
Array comprehensions were removed in Babel 6.0
As far as I know there are currently no big API changes happening in v8, plus the abstraction layer for native node packages (nan, Native Abstracts for Node.js) has been, afaik, quite excellent at shielding native package developers from a lot of potential API breakage -- so generally it can be expected that there will be either no or very minor implications for native packages -- and no implications at all for non-native packages since those work purely with the node API which is not tied to the v8 API.
We'll know more once the v8 project's API changes doc will be updated with 5.1 info, and node core has created its vee-eight-5.1 branch.
EDIT: added clarification about non-native packages; clarity
...and performance improvements are always good!
