[esprehn]

Web Streams do feel rather painful compared to other languages. The author ends up basically describing kotlin flows which are great and I wish the web would adopt that model (Observables wanted to be that but the API is much worse than flows in practice).

Fwiw the original Streams API could have been simpler even without async iterators.

  interface Stream<T> {
    // Return false from the callback to stop early.
    // Result is if the stream was completed.
    forEach(callback: (chunk: T) => Promise<boolean | undefined>): Promise<boolean>
  }

Similarly adding a recycleBuffer(chunk) method would have gone a long way towards BYOB without all the ceremony.

If we're optimizing allocations we can also avoid all the {done,value} records and return a semaphore value for the end in the proposed API.

(Web) API design is really difficult and without a voice in the room pushing really hard on ergonomics and simplicity it's easy to solve all the use cases but end up with lots of awkward corners and costs later.