Initial atom state

Currently the most issue I see with atoms is initial atom state which especially on server cant be inside any global objects ie localStorage etc. (setEffect is not working on server too)

Creating atoms and passing them through a context - loss of main advantages (u would need to create dependent atoms in context etc)

Probably passing Provider value to atom on initial call could solve this?

I.e.

// atom already have getter fn as param so I call atom with state dependent on context subatom.

const myAtom = subatom(ctx => ctx.someVal)

....
// in some component

<InitialJotaiValueProvider value={{ someVal: 123 }}> ...

Or probably some other beautiful api can be available.

PS: Api like above can be typed well like

const { InitialValueProvider, subatom} = createBlaBla<ValueType>()

[dai-shi]

You are welcome!

For someone interested, it’s like this.

const weakAtomFamily = (initializeRead, initializeWrite) => {
  const atoms = new WeakMap()
  return (obj) => {
    if (atoms.has(obj)) return atoms.get(obj)
    const newAtom = atom(initializeRead(obj), initializeWrite && initializeWrite(obj))
    atoms.set(obj, newAtom)
    return newAtom
  }
}

[dai-shi]

#158 added shouldRemove. There can still be cases weakAtomFamily works better. We can add it to utils if someone suggests some use cases.

For now, I don’t think we have any actions for this issue, so closing this.