Stage 2 proposal for public class fields in ECMAScript
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Latest commit 07f3d38 Aug 18, 2016 @danez danez committed with jeffmo Correct link to specs (#49)
The link is also wrong in the description of the repo.

README.md

ES Class Fields & Static Properties

This presents two related proposals: "class instance fields" and "class static fields". "Class instance fields" describe properties intended to exist on instances of a class (and may optionally include initializer expressions for said properties). "Class static fields" are declarative properties that exist on the class object itself (and may optionally include initializer expressions for said properties).

This proposal is currently at Stage 2.

Latest spec text: https://tc39.github.io/proposal-class-public-fields/