Allow gathering a specific amount of values instead of all of them

[Richienb]

It would be useful if this module could only take a specific amount of values from an observable to achieve a similar purpose as p-event:

const observableToPromise = require('observable-to-promise');

(async () => {
	console.log(await observableToPromise.one(Observable.of(1, 2, 3, 4, 5)));
	//=> 1

	console.log(await observableToPromise(Observable.of(1, 2, 3, 4, 5), {maximumValues: 3}));
	//=> [1, 2, 3]
})();

// @sindresorhus

[sindresorhus]

Sure, but should be called count as the suggested naming is misleading as it can never be below max, so it's not really a max.

[Richienb]

@sindresorhus

it can never be below max, so it's not really a max.

const observableToPromise = require('observable-to-promise');

(async () => {
	console.log(await observableToPromise(Observable.of(1, 2, 3, 4), {maximumValues: 5}));
	//=> [1, 2, 3, 4]
})();

[sindresorhus]

achieve a similar purpose as p-event:

Then it's not the same purpose as p-event though. p-event waits until it has count elements, not less, not more.

What's your use-case for needing max?

[Richienb]

@sindresorhus

What's your use-case for needing max?

I have an observable that emits newly received data but I only want the very next chunk of data emitted and nothing else.

p-event waits until it has count elements, not less, not more.

An observable could complete() before the specified amount of values has been emitted so it's best to call it maxCount.

[sindresorhus]

Alright 👍🏻

[JounQin]

firstValueFrom and lastValueFrom like rxjs would be great.