MDN Docs: Async Iteration

[jahzielv]

Creating MDN documentation for the Async Iteration proposal

Adapted from Florian Scholz's notes.

Iteration protocol reference page:

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols needs to talk about the async iteration protocol.

Symbol.asyncIterator

Note: Docs could probably be derived from Symbol.iterator https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/iterator. It's already listed on the Symbol page: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol#Well-known_symbols

• New page to be created here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/asyncIterator

• Compat data update here: https://github.com/mdn/browser-compat-data/blob/master/javascript/builtins/Symbol.json#L58

• ⏳New interactive example here: https://github.com/mdn/interactive-examples/tree/master/live-examples/js-examples/symbol (PR submitted here)

for-await-of

• Needs to be listed here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements#Iterations

• New reference page here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for-await...of

• New compat data entry here: https://github.com/mdn/browser-compat-data/blob/master/javascript/statements.json

• ⏳ New interactive example here: https://github.com/mdn/interactive-examples/tree/master/live-examples/js-examples/statement (PR submitted here)

Async generators

• ⏳Additional async function* reference page: (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_generator_function?) (Issue opened here)

• Compat data (already completed here)

• Interactive example (already completed here)

APIs that use async iterators / generators

• Identify other APIs that use async iteration.
  • WHATWG Streams

Guide page updates

We have https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Iterators_and_generators
Unfortunately we have no dedicated guide page yet on async JS programming. We want to create that at some point, though. See https://bugzilla.mozilla.org/show_bug.cgi?id=1305261
More brainstorming on that here: https://docs.google.com/document/d/1ko8Xt5JaFVuXjEOHSyhw8MaxKPTbKiX6Qc7EXtczKUA/edit?ts=5b55b98b#heading=h.5tv0p4d6vqmu

[jahzielv]

Updated list; removed item requesting mentioning async iteration in the Streams MDN doc.