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ComponentScope

const ComponentScope: MoleculeScope< undefined >

Component scope is handled in a special way.

Unlike other scopes, it will always have a unique value for every component it’s used in. That makes it possible to create component-scoped state using molecules in the same way that global state or other scoped state is created.

Example

Counter state (React)

const CounterM = molecule((_, scope) => {
   scope(ComponentScope);
   return atom(0);
});

// State will NOT be shared between components
const useCounter = () => useAtom(useMolecule(CounterM));

// The above is equivalent to:
// const useCounter = useAtom(useRef(atom(0)).current);

// The above is also equivalent to:
// const useCounter = useState(0)

Example

Counter state (Vue)

const CounterM = molecule((_, scope) => {
   scope(ComponentScope);
   return ref(0);
});

// State will NOT be shared between components
const useCounter = () => useMolecule(CounterM);

// The above is equivalent to:
// const useCounter = () => ref(0)

Source

ComponentScope.ts:42