AES2018 and ES2019

Beginning with ECMAScript 2015, the TC-39 committee moved to begin releasing a new ECMA specification each year. Doing so allows them to collect all individual proposals that are at a sufficiently advanced stage and package them as a single bundle. This packaging is of limited importance, however, as browser vendors tend to adopt proposals in a piecemeal fashion. When a proposal has reached stage 4, its behavior will not change, it is likely to be included in the next ECMAScript release, and browsers will begin adopting the proposal's features at their discretion.

The ECMAScript 2018 proposal was finalized in January 2018 and features enhancements for asynchronous iteration, the rest and spread operators, regular expressions, and promises. TC-39 maintains a GitHub repository ( that you can use to track the status of various proposals:



Asynchronous execution and the iterator protocol are two extremely pervasive themes in new ECMAScript features over recent releases. Asynchronous execution involves releasing control of the execution thread to allow slow operations to finish before regaining control, and the ...

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