Idiom for a pre-made already resolved ES6 promise

Asked Oct 10 '18 at 18:50

Active Oct 10 '18 at 18:58

Viewed 19 times

I have a .then() waterfall with promise steps, and sometimes a promise doesn't apply. So I have code like this:

var maybe_noop_promise;
if (some_condition)
    maybe_noop_promise = fetch(...).then(...)... // work need be done
else
    maybe_noop_promise = /* code for resolved promise (?) */

Were I using jQuery, there's a suggestion that this can be done with $.when(). And it appears Promise.all([]) is resolved, which I guess is fine, though I don't know if that is wasteful or slow.

Is there a favored idiom for a pre-cooked resolved promise?

edited Oct 10 '18 at 18:58

asked Oct 10 '18 at 18:50

HostileFork says dont trust SE

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`Promise.resolve(value)`. – Bergi Oct 10 '18 at 18:59
@Bergi Thanks. Though this is an example of what I would call a "good duplicate" in that I would never have found the other question with the search terms I was using. Sidenote that `Promise.resolve()` appears to work with no value passed. – HostileFork says dont trust SE Oct 10 '18 at 19:04
Yes, `value` is just taken as `undefined` if you pass no arguments. – Bergi Oct 10 '18 at 19:10

Idiom for a pre-made already resolved ES6 promise

0 Answers0