In the test I got this question. Answered 5.1 - proceeded from the fact that all browsers use it with features 6.1. As far as I know, to write on 6.1 you need to use all sorts of beibels and the like. I did not understand whether I answered correctly or not. Can anyone suggest what version is still relevant at the moment? Or this question is initially incorrect - both versions are relevant?

  • The JS specification is in the public domain and if it is adopted, therefore it is relevant, how does the adoption of the new standard occur? (in brief). There is a table of proposals where each developer can write his decision with a full description and profit for the community, then his proposal is considered (something like a commission), then if there is a profit, you can see the possibility of implementation in modern main browsers, if everything is ok, Only then it is decided to include this function in the standard. So if the standard is adopted, it is relevant! I missed some step, I don’t remember what ... - Oma
  • @Oma, they forgot about the donkey, here the standard is powerless :) - user207618
  • @Other, No need to talk here :-) EDGE is quite nothing :-) - Grundy
  • @Grundy versus IE8 is possible. - user207618

1 answer 1

Current finished specification

ECMA-262
7ᵗʰ Edition / June 2016
ECMAScript® 2016 Language Specification

The draft specification can be seen on the githaba: https://tc39.imtqy.com/ecma262/

Hence the question: what is the current version?

There may be several answers to this question:

  1. The version of the specification that has been discussed
  2. Latest available version
  3. Most browser supported

Judging by browser support, even the sixth version of the standard is not fully supported anywhere. Mainly due to part of the dedicated modules and tail recursion optimization.

On the other hand, if you check maintainability, then

  • ES6 is supported by major browsers at 95% + implementation.
  • ES 2016 is a bit worse situation, implementation at 70%

The difficulty of separation lies in the fact that browsers are not required to fully implement one version of the standard in order to proceed to the next one. Because of this, it turns out that all versions of specifications may not be fully implemented and the code running in one browser may not work in another.

Based on this, we can assume that the current version is 5, or the sixth version of the specification, as the most supported at the moment (March 2017).