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var es2040 = require("es2040")

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es2040 v1.2.6

browserify transform that compiles a selection of ES6 to valid ES5

es2040 stability

npm version downloads js-standard-style

browserify transform that compiles a selection of ES6 features to valid ES5:

  • fat arrows - make inline functions cute-looking
  • template strings / tagged templates - enable DSLs inside of JS
  • const - using const by default makes it easy to spot where values are being redeclared
  • object destructuring - const { a, b } = { a: 1, b: 2 }
  • array destructuring - const [a, b] = [1, 2]
  • default parameters - ({ a = 1, b = 2 } = {}) => a
  • rest parameters - (a, b, ...args) => {}
  • spread literals - f(a, b, ...args)
  • short-hand properties - return { a, b }
  • computed properties - return { [a]: b }

Because, in hindsight, we can do without most of ES6.

Forked from es2020 for those of us with slightly worse vision.


Via package.json (recommended):

  "browserify": {
    "transform": [

Via CLI:

$ browserify client.js -t es2040

Via Node API:

const browserify = require('browserify')


Is this a joke?

Not really. The TC39 does not represent my interests, and the features they introduce are not useful for the stuff I'm doing. I'm bloody serious. A few good things have been introduced, so that's what we're backporting to older browsers.

Can you not?

If the TC39 had an open standards process perhaps this wasn't needed. But as it stands they're an unwelcoming club, so I get to poke fun at this situation that otherwise fills me with sadness. Feel free to poke fun at me too. Or if you're angry that someone would make fun of the hard work the TC39 has done, feel free to ignore this project. Do whatever, I'm doing the same.

Can you include feature X?

Maybe. Open an issue, make a case and we can discuss it. Just remember that this project is not democratically governed.


$ npm install es2040

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