Function useState

packages/react-debug-tools/src/ReactDebugHooks.js:280–300

(
  initialState: (() => S) | S,
)

}

function useState<S>(
  initialState: (() => S) | S,
): [S, Dispatch<BasicStateAction<S>>] {
  const hook = nextHook();
  const state: S =
    hook !== null
      ? hook.memoizedState
      : typeof initialState === class="st">'function'
        ? class="cm">// $FlowFixMe[incompatible-use]: Flow doesn't like mixed types
          initialState()
        : initialState;
  hookLog.push({
    displayName: null,
    primitive: class="st">'State',
    stackError: new Error(),
    value: state,
    debugInfo: null,
    dispatcherHookName: class="st">'State',
  });
  return [state, (action: BasicStateAction<S>) => {}];
}

function useReducer<S, I, A>(
  reducer: (S, A) => S,