Currently, the prototype changes proposed for inclusion in the ECMAScript standard have been submitted for preliminary discussions (Stage 0).
It is mentioned that at tHaving explicit type information will prevent many errors in the development process, it will provide the opportunity to use additional optimization techniques, simplify debugging, and make the code more readable and easier for third-party developers to modify and maintain.
At the same time, unlike the specified type information via JSDoc annotations specified as comments, the direct specification of types directly in variable definition constructs it will make the code more visual, understandable and easier to edit.
Of the types, it is proposed to add "string", "number" and "boolean", which can be used when defining variables, function parameters, object elements, class fields, typed arrays ("number"). It is also proposed to provide support for mixed types ("string | number") and generics.
Given all of this, we plan to present this proposal for Stage 1 at the next March 2022 plenary meeting of TC39. We will do so with the support and guidance of our co-champions of this proposal, Rob Palmer at Bloomberg and Romulo Cintra at Igalia.
Reaching Stage 1 would mean that the standards committee believes compatible type syntax for ECMAScript is worth considering. This is not a sure thing: there are many valuable perspectives within the committee, and we expect a certain amount of skepticism. A proposal like this will receive a lot of comment and proper scrutiny. It can involve a lot of design changes along the way and it can take years to get results.
at the next meeting of March of the TC39 committee, it is planned to move to the first stage consideration of the proposal with the participation of the ECMA expert community.
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