Ready to upgrade to V8 4.2?

[domenic]

Counting down the weeks, Chrome 42 should be coming out any day now... That means it's time for V8 4.2!

#1026 was the last discussion. Looks like this will require a 2.x since everyone will need to recompile their addons?

Selflishly, I want this ASAP... Native classes will be huuuge.

[cjihrig]

+1. Are there any semver major PRs remaining that can go into the next branch?

Are there nightlies or anything for the next branch? If not, some sort of preview release would be nice.

[rvagg]

nightlies for next were on my TODO list sorry, I'm obviously overstretched at the moment but I'll try and get to this ASAP cause this is pretty important (and fun)

[cjihrig]

@rvagg I'd be glad to offer help if you can use it.

[rvagg]

@iojs/build / @Fishrock123 I've adjusted iojs+release+nightly on Jenkins to take an additional parameter: buildtype which can be either next or next-nightly, it's primarily used to put the nightlies into the right place and set their version name appropriately, it won't do any checks that you are giving it a commit on the next branch though so you still need to use your brain a little when making a nightly.

First nightly built using this has landed here: https://iojs.org/download/next-nightly/ and the rest will go in the same place.

$ cat foo.js

"use strict"

class Dude {
  constructor() {
    this.rnd = Math.random()
  }

  toString() {
    return 'Whoooooooa dude!'
  }
}

class Whoa extends Dude {
  constructor() {
    super()
    console.log(`
      Java me up scotty!
      ${ JSON.stringify(process.versions) }
      ${ JSON.stringify(this.derp('foo', 'bar')) }
      ${ this }
    `)
  }

  derp(...args) {
    return {
        [this.rnd]: 'eh?'
      , [args[0]]: args[1]
    }
  }
}

new Whoa()

$ node --harmony-computed-property-names --harmony-rest-parameters foo.js

      Java me up scotty!
      {"http_parser":"2.3.0","node":"2.0.0-next-nightly2015041138225a7203","v8":"4.2.77.13","uv":"1.4.2","zlib":"1.2.8","ares":"1.10.0-DEV","modules":"44","openssl":"1.0.1m"}
      {"0.6709401244297624":"eh?","foo":"bar"}
      Whoooooooa dude!

Wait, what language is this?

/cc @iojs/evangelism

[rvagg]

@othiym23 does npm not like my extended prerelease here?

$ npm i xtend@latest
npm http request GET https://registry.npmjs.org/xtend
npm http 304 https://registry.npmjs.org/xtend
npm WARN engine xtend@4.0.0: wanted: {"node":">=0.4"} (current: {"node":"2.0.0-next-nightly2015041138225a7203","npm":"2.7.1"})
xtend@4.0.0 node_modules/xtend

[yosuke-furukawa]

yay! v8 4.2 shipped class syntax by default.

[YurySolovyov]

I thought M43 already branched

[Fishrock123]

@rvagg I think npm sometimes warns for pre-releases.

derp(...args) {

oooo, 4.2 supports spread by default? :D

Edit: is that just --harmony-rest-parameters?

[bricss]

+1

[leecade]

Looking forward 👍

[shekhei]

+1 been using classes with the harmony flag for quite a while, code is much cleaner, and it still retains all the prototypal stuff internally, best of both worlds.

What else is delivered along with 4.2? anybody's got a link to the list?

[bnoordhuis]

What else is delivered along with 4.2? anybody's got a link to the list?

Classes and object literals are no longer behind a flag.

Rest parameters, computed property names and Unicode escapes ('\u{xxxx}') are new and behind flags. There is a separate flag for Unicode escapes in regular expressions.

Preliminary support for strong mode (tracking bug).