Updates from the 89th TC39 meeting

There were several items on the agenda, this post focuses on feature proposals and their progress from the meeting that was held between March 28th-31st, 2022.

Stage 1:

• Type Annotations: Enable developers to add type annotations.

• Function once: Standardize once function in the language core.

Stage 2:

• Decorator metadata: Decorators can associate metadata with the value that is being decorated. (P.S: The repo shall be updated with content.)

Stage 3:

• RegExp set notation + properties of strings: extend the syntax for character classes to add support for set difference/subtraction, set intersection, and nested character classes.

• Decorators (sans metadata): Functions called on classes, class elements, or other JavaScript syntax forms during definition.