Store and array, how to reset it

[pecoram]

Hi,
I have two questions.

1. what is the best way to reset a store like this?

interface CollectionStore {
	collections: CollectionExtended[];
	collectionsLength: number;
}

const initialCollectionStore: CollectionStore = {
	collections: [],
	collectionsLength: 0,
};

const [collectionStore, setCollectionStore] = createStore<CollectionStore>(initialCollectionStore);

2. is it better to create the store as an object (as done before) or as an array?

type CollectionStore = CollectionExtended[];
const initialCollectionStore: CollectionStore = [];

[agammann]

Use a function that returns fresh initial state, then pass it through reconcile when resetting:

const makeInitial = () => ({
  collections: [],
  collectionsLength: 0
});

const [collectionStore, setCollectionStore] = createStore(makeInitial());

function resetCollections() {
  setCollectionStore(reconcile(makeInitial()));
}

The fresh object matters because the object passed to createStore is the store's backing data: updates can modify it. Reusing that same initialCollectionStore later may therefore restore values you've already changed.

An object is convenient when the collection has additional state, such as loading/error information. A top-level array is fine if the array itself is all you need. Reset that form with:

setCollections(reconcile([]));

If collectionsLength always means collections.length, you can read the array's length directly instead of maintaining a second value that must stay synchronized. I checked the object reset and top-level array reset with Solid 1.9.17.