export type AtomKey = string | number | symbol;
export type AtomStore = Map<AtomKey, any>;
export type AtomStoreUpdate = Record<AtomKey, any>;
export type AtomUpdater<Value, Update = Value> = (value: Value) => Update;
export type AtomValueUpdate<Value, Update = Value> = Update | AtomUpdater<Value, Update>;
export type AtomSelector<Value, Selected> = (value: Value) => Selected;
export type AtomGetter<Value> = () => Value;
export type AtomSetter<Value, Update = Value> = (update: AtomValueUpdate<Value, Update>) => Value;
export type AtomSubscribe<Value> = (next: (value: Value) => void) => () => void;
export type Atom<Value, Update = Value> = {
    readonly key: AtomKey;
    readonly def: Value;
    get: AtomGetter<Value>;
    set: AtomSetter<Value, Update>;
    sub: AtomSubscribe<Value>;
};
export type DynamicAtomGetter = <Value, Update = Value>(atom: Atom<Value, Update>) => Value;
export type DynamicAtomSetter = <Value, Update = Value>(atom: Atom<Value, Update>, update: AtomValueUpdate<Value, Update>) => Value;