Re:JavaScript Illustrated: Promises
by fimbulvetr on Friday October 11, 2019 @09:49AM
(#21224298)
I don't believe that's true - I haven't had the time to test this yet, but I believe that the scenarios where a power user would prefer to have a then. Await's are definitely easier because they allow you to maintain the "procedural" feel of your code, but promises allow you to kick off several async things at once so that they take place at the same time. For instance, if I have a collection of promises that each take 10 seconds I would want them to kick off at the same time rather than sequentially - so both take 10 seconds wall clock time rather than 20 seconds one after the other. To my knowledge, the only sane way to pull this off is by using promises.all with a then. Please correct me if I'm wrong.
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Re:JavaScript Illustrated: Promises
by davidonhacker on Friday October 11, 2019 @09:55AM
(#21224375)
Very easily like this.
await Promise.all([promise, promise]);
That's a good question. In addition to the sibling reply (which answers this perfectly) you can also do what I do.
Array.prototype.forEachAsyncParallel = async function (iterateFunction) {
await Promise.all(this.map(iterateFunction));
}
Note 2: read note 1.