Feature watch: ECMAScript 2017

By Axel Rauschmayer

Feature watch: ECMAScript 2017

The feature set of ES2016 was recently finalized. This blog post tracks what features may be included in ES2017. I will continually update it.

Proposed ECMAScript features

Recall that every ECMAScript feature proposal goes through stages:

  • Stage 4 means that a feature will probably be in the next release.
  • Stage 3 means that a feature still has a chance of being included in the next release.

The following features are currently at stage 3:

If you are wondering what stages other proposed features are in, consult the readme of the ECMA-262 GitHub repository.

SIMD.JS – SIMD APIs + polyfill (John McCutchan, Peter Jensen, Dan Gohman, Daniel Ehrenberg)

SIMD stands for “single instruction, multiple data”, the ability of a CPU to apply an operand to vectors of values (instead of single values). One popular example of a SIMD instruction set is SSE (Streaming SIMD Extensions), as supported by Intel processors.

This is a short code example, consult the sources below for more information.

    var a = SIMD.float32x4(1.0, 2.0, 3.0, 4.0);
    var b = SIMD.float32x4(5.0, 6.0, 7.0, 8.0);
    var c = SIMD.float32x4.add(a,b);

Further reading:

Source:: 2ality