Function useStoreMapBase

src/react/apiBase.ts:178–257

(
  [configOrStore, separateFn]: [
    configOrStore:
      | {
          store: Store<State>
          keys: Keys
          fn(state: State, keys: Keys): Result
          updateFilter?: (update: Result, current: Result) => boolean
          defaultValue?: Result
        }
      | Store<State>,
    separateFn?: (state: State, keys: Keys) => Result,
  ],
  scope?: Scope,
)

}

export function useStoreMapBase<State, Result, Keys extends ReadonlyArray<any>>(
  [configOrStore, separateFn]: [
    configOrStore:
      | {
          store: Store<State>
          keys: Keys
          fn(state: State, keys: Keys): Result
          updateFilter?: (update: Result, current: Result) => boolean
          defaultValue?: Result
        }
      | Store<State>,
    separateFn?: (state: State, keys: Keys) => Result,
  ],
  scope?: Scope,
): Result {
  let fn: (state: State, keys: Keys) => Result
  let updateFilter: (update: Result, current: Result) => boolean =
    basicUpdateFilter
  let defaultValue: Result | undefined
  let store: Store<State>
  let keys: Keys
  if (separateFn) {
    fn = separateFn
    store = configOrStore as Store<State>
    keys = [] as unknown as Keys
  } else {
    ;({
      fn,
      store,
      keys,
      defaultValue,
      updateFilter = basicUpdateFilter,
    } = configOrStore as any)
  }
  if (!is.store(store)) throwError('useStoreMap expects a store')
  if (!Array.isArray(keys)) throwError('useStoreMap expects an array as keys')
  if (typeof fn !== 'function') throwError('useStoreMap expects a function')

  const subscribe = React.useCallback(
    (fn: () => void) => createWatch({unit: store, fn, scope}),
    [store, scope],
  )
  const read = React.useCallback(
    () => stateReader(store, scope),
    [store, scope],
  )

  const stateRef = React.useRef<State>()
  const valueRef = React.useRef<Result>()
  const keysRef = React.useRef(keys)

  const value = useSyncExternalStoreWithSelector(
    subscribe,
    read,
    read,
    state => {
      if (stateRef.current !== state || !keysEqual(keysRef.current, keys)) {
        let result = fn(state, keys)