Missing subscribeKeys(store, keys, cb) method ?

[Jeremboo]

We have both store.subscribe(cb) and store.listen(cb) to decide if we want to call the listeners immediately on subscribe or not.

So why not having the same with subscribeKeys(store, keys, cb) along listenKeys(store, keys, cb) ?

import { listenKeys, type StoreValue } from 'nanostores';

export function subscribeKeys<
  SomeStore extends { get: () => StoreValue<SomeStore>; setKey: (key: any, value: any) => void }
>(
  $store: SomeStore,
  propsToListen: SomeStore extends { setKey: (key: infer Key, value: never) => unknown } ? readonly Key[] : never,
  callback: (_props: StoreValue<SomeStore>) => void
) {
  listenKeys($store, propsToListen, callback);
  callback($store.get());
}

I'm using it in prod and it's working pretty good !

[ai]

Do you have a real use case for that? If yes, we can add.

[Jeremboo]

The use case is similar to using the already implemented store.subscribe(cb) method.
It's to trigger the callback immediately on subscribe.

I'm using it in vanillaJS. For instance to init my JS classes with values from the store.

Exemple :

export default class MyExample {
  valueA = 0;

  constructor() {
    subscribeKeys(webgl, ['valueA'], this.handlePropsChanged);
  }

  handlePropsChanged = ({ valueA }) => {
    if (valueA != this.valueA) {
      // Animate with the new values directly instantiation and all the other times
      gsap.to(this, { valueA, valueB, duration: 1 });
    }
  }
}

If it's a use case you don't want to support, maybe for consistency store.subscribe(cb) should be removed ?

[ai]

Send PR with a function to next branch