Q91. Can useState take a function as an initial value?
Yes, `useState` can take a function as an initial value, and this is a useful feature in React called **lazy initialization**. This function is also known as **initialize...
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Q92. What types of values can `useState` hold?
The `useState` hook accepts different types of values. * Primitives: `number`, `string`, `boolean` * Arrays * Objects * Functions * `null` or `undefined` But you needs to...
Q93. What happens if you call `useState` conditionally?
As per rules of React Hooks, hooks must be called unconditionally. For example, if you conditionally call it: ```js if (someCondition) { const [state, setState] = useStat...
Q94. Is useState Synchronous or Asynchronous?
The `useState` hook is synchronous, but state updates are asynchronous. When you call `useState()`, it runs synchronously and returns the state variable and setter functi...
Q95. Can you explain how useState works internally?
React’s hooks, including `useState`, rely on some internal machinery that keeps track of state **per component** and **per hook call** during rendering. Here's a simplifi...
Q96. What is `useReducer`? Why do you use useReducer?
The `useReducer` hook is a React hook used to manage **complex state logic** inside **functional components**. It is conceptually similar to **Redux**. i.e, Instead of di...
Q97. How does `useReducer` works? Explain with an example
The `useReducer` hooks works similarly to Redux, where: * You define a **reducer function** to handle state transitions. * You dispatch actions to update the state. **Cou...
Q98. Can you combine **useReducer** with **useContext**?
Yes, it's common to combine **useReducer** with **useContext** to build a lightweight state management system similar to Redux: ```js const AppContext = React.createConte...
Q99. Is dispatch from useReducer asynchronous and does it update state immediately?
The `dispatch` function returned by `useReducer` is **not asynchronous** — it is a **synchronous** function call. When you call `dispatch(action)`, React **synchronously*...
Q100. How does useContext works? Explain with an example
The `useContext` hook can be used for authentication state management across multiple components and pages in a React application. Let's build a simple authentication flo...