
V8 release v6.6 - stablemap
https://v8project.blogspot.com/2018/03/v8-release-66.html
======
Klathmon
The improvements in Promise performance are going to really help in
async/await heavy codebases, and it's in time for Node 10!

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bcherny
A bit buried - V8 also supports tracing DOM-related memory leaks (exposed in
devtools)! [https://v8project.blogspot.com/2018/03/tracing-js-
dom.html?m...](https://v8project.blogspot.com/2018/03/tracing-js-dom.html?m=1)

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tim_hutton
Is there still a need for performant JavaScript now that we have WebAssembly?

Edit: Apologies for wording this poorly. Clearly there is a need for
performant JavaScript. My question is more about how much we expect
WebAssembly to take over from what JavaScript is currently used for. Thank you
for all the insightful comments!

~~~
fvdessen
JavaScript ES6 is actually a very pleasant language to program in. JS already
had good foundations with first class JSON, closures and event based
asynchronous programming. Now it has a modern syntax with await, classes,
destructuring, default parameters, the spread operator, etc. Add to that an
incredible debugger and amazing performance. Frankly at this point JS can
stand on its own as a great programming language.

~~~
tim_hutton
I like JavaScript a lot, I've got no problem with it. But when WebAssembly can
access the DOM (or replace it) it seems likely that performance-critical code
will use that instead.

~~~
chatmasta
Sure, the major frameworks may move to wasm under the hood, but the users of
the library will still likely be coding in ES6. We will probably see a lot of
APIs where the backend is implemented in wasm with a friendly, scriptable
frontend in typical ES6.

That said, I’m actually skeptical wasm will ever find much of a use case with
the DOM. The browser itself is already heavily optimized for working with the
DOM, so wasm is unlikely to be competitive in speed except for specific use
cases.

~~~
notheguyouthink
> Sure, the major frameworks may move to wasm under the hood, but the users of
> the library will still likely be coding in ES6. We will probably see a lot
> of APIs where the backend is implemented in wasm with a friendly, scriptable
> frontend in typical ES6.

Why? If WASM has access to the DOM, _and_ it's competitive in terms of
performance - why would JS still by the goto? At that point, people will just
choose whatever language they want, I don't see JS having an advantage there
any longer. Especially since many people don't want to use JS to begin with,
but have been forced to.

> That said, I’m actually skeptical wasm will ever find much of a use case
> with the DOM. The browser itself is already heavily optimized for working
> with the DOM, so wasm is unlikely to be competitive in speed except for
> specific use cases.

I'll be sad if that is true. Though, I'd even be willing to take minor
performance hits to use the languages/etc I want. How much of a hit I'd be
willing to take would really depend on the application needs, of course.

~~~
scottmf
Many of us _do_ want to use JS. The language has evolved a lot over the past
few years and people love it.

Client-side JavaScript isn't going anywhere. Look how popular Node is despite
all the alternatives.

~~~
notheguyouthink
> Many of us do want to use JS. The language has evolved a lot over the past
> few years and people love it.

No one _(with any sense)_ thinks JS is somehow going to be deleted. Nor am I
saying JS is going anywhere - if anything, _I 'm not even talking about JS_,
I'm not sure why you pointed out that JS is going to exist afterwards. Do I
misunderstand your point?

> Client-side JavaScript isn't going anywhere. Look how popular Node is
> despite all the alternatives.

Well to be clear, there isn't alternatives, if the user wants a shared
tooling, shared libraries, shared language.

I don't think Node became popular years ago because JavaScript is so wooping
awesome. Hell, when NodeJS came out transpilers (CoffeeScript/etc) were
massively popular because of how much many people hated JavaScript.

Node was popular _despite_ many peoples dislike for the language. I worked for
~4 years at a company who built an entire platform in CoffeeScript, as did a
few other companies we worked with.

That's not to say that JavaScript is terrible, ES6+ is becoming really nice.
I'm just saying, Node's popularity is clearly not evidence of JavaScript being
awesome. Node is a symptom of people wanting a singular environment, and not
having any choice about JavaScript.

~~~
scottmf
Perhaps I misunderstood your point. You seemed to ask why people would want to
use JS once WASM effectively puts it on a level playing field with other
languages.

~~~
notheguyouthink
Ah nah, I meant more like - if you wanted to, why wouldn't you. Not that
anything is explicitly better than anything else.

It sounded like people were claiming that WASM cannot dethrone JS, that JS
will always be the language of the web, etcetc. So my question was more.. Why?

Personally I don't think it is _(clearly haha)_. Once DOM access is
reasonable, I think many (myself included) will move away _quickly_. Web
frameworks are not _that_ hard, so the existing ecosystem of languages is a
bit of a meaningless argument as I see it. Hell, even within JS, the ecosystem
is largely isolated solos of code. Eg, sure I can choose between React,
Angular, Ember, etcetc - but I wouldn't choose two of them at the same time.
The ecosystem in that case only helps me in that I _can_ choose, but they're
rarely tools I collectively use.

So back to my original point, myself, and I imagine my shop, would make the
switch pretty quickly as soon as WASM is viable for our target languages.
Viable means page load execution, memory, speed, etc - all variable parameters
depending on the project of course.

~~~
_Tev
> It sounded like people were claiming that WASM cannot dethrone JS, that JS
> will always be the language of the web, etcetc. So my question was more..
> Why?

You seem to be missing the biggest (at least to me) advantage of JS - how dumb
it is.

It's great that beginners don't have much to learn. They do not need any
complex environment setup. And even seniors get benefit of easy onboarding.

And considering web will always be primarily about UI i.e. high level code
writable by any random guy without CS degree, why would JS lose its dominance?

~~~
notheguyouthink
Being the top language and being the goto might be different though.. although
I'm not sure how to properly word the two, but what I mean is:

A goto language is the language that most people are going to use because of
the benefits for the problem domain. Eg, you're not going to write an embedded
device application with a GC language like JS/Py/Go/etc. You're far better off
with a low level, low memory and predictable language.

Right now, JS is the goto for the web. It's actually not the only "choice",
transpilers exist for many languages to JS, but it slows the app down,
increases size, etc. So while people have options, the disadvantages of other
Langs on the web make JS the goto.

Saying that JS will no longer be the goto _(or however you want to word it)_
doesn't mean people will stop using JS any more than embedded systems not
using Python hurts Python. But it does mean people have options, and JS is a
language of choice now, not requirement. At least, that's my dream - hopefully
WASM provides that.

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cat199
> freeing it up to execute more JavaScript and reduce jank.

^ I 'grok' this, but is there not a more proper technical term for this given
the tone?

not complaining.. just wondering

~~~
tlb
Jank is the technical term. [https://www.chromium.org/developers/how-
tos/trace-event-prof...](https://www.chromium.org/developers/how-tos/trace-
event-profiling-tool/anatomy-of-jank)

