jotai-scope

👻🔭

https://jotai.org/docs/integrations/scope

Pro Tips

1. Within a ScopeProvider, although an atom may not be scoped, its atom.read function could be called multiple times. Therefore, do not use atom.read to perform side effects.

   NOTE: Async atoms always have side effects. To handle it, add additional code to prevent extra side effects. You can check this issue as an example.

2. Scoping a derived atom has no behavioral effect. Avoid it.

   Derived atoms are merely proxies of primitive atoms. When scoping a derived atom, although the atom itself is copied, all of those copies still reference the same primitive atom, so their values are still shared.

   It is a common pattern in Jotai to wrap the primitive atom within a utility function. To scope it properly, you should expose the primitive atom and then apply the scoping to it.

   function someAtomUtility(initialValue) {
     // This is the primitive atom. Return it and then scope it.
     const anAtom = atom(initialValue)
   
     // Be careful, this is a derived atom! Scoping it has no effect.
     return atom(
       (get) => get(anAtom),
       (get, set, update) => set(anAtom, update)
     ),
   }