Syntax-Supported Async Iteration

[zenparsing]

With the current async iterator design, syntax-supported iteration should be made async-aware. That is, when executed within an async function, it should await promises for iteration results.

• Spread syntax in array literals and argument lists
• Destructuring array patterns
• For/of statements
• Delegating yield (yield *)

GetIterator is also used in various collection types like Array, Map, and Set. I seems like those uses of iteration demand synchronous iterators, however. More thought is needed there.

[zenparsing]

We've decided not to pursue this path.