Q611. List down some of the features of ES6
Below are the list of some new features of ES6, 1. Support for constants or immutable variables 2. Block-scope support for variables, constants and functions 3. Arrow fun...
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Q612. How does React Fiber works? Explain in detail.
React Fiber is the **core engine** that enables advanced features like **concurrent rendering**, **prioritization**, and **interruptibility** in React. Here's how it work...
Q613. What is ES6?
ES6 is the sixth edition of the javascript language and it was released in June 2015. It was initially known as ECMAScript 6 (ES6) and later renamed to ECMAScript 2015. A...
Q614. What is the useId hook and when should you use it?
The `useId` hook is a React hook introduced in React 18 that generates **unique IDs** that are stable across server and client renders. It's primarily used for **accessib...
Q615. Can I redeclare let and const variables?
No, you cannot redeclare let and const variables. If you do, it throws below error ```bash Uncaught SyntaxError: Identifier 'someVariable' has already been declared ``` *...
Q616. What is the useDeferredValue hook?
The `useDeferredValue` hook is used to **defer updating a part of the UI** to keep other parts responsive. It accepts a value and returns a "deferred" version of that val...
Q617. Does the const variable make the value immutable?
No, the `const` variable doesn't make the value immutable. But it disallows subsequent assignments(i.e, You can declare with assignment but can't assign another value lat...
Q618. What is the useTransition hook and how does it differ from useDeferredValue?
The `useTransition` hook allows you to mark certain state updates as **non-urgent transitions**, keeping the UI responsive during expensive re-renders. It returns a `isPe...
Q619. What are default parameters?
In ES5, we need to depend on logical OR operators to handle default values of function parameters. Whereas in ES6, Default function parameters feature allows parameters t...
Q620. What is the useSyncExternalStore hook?
The `useSyncExternalStore` hook is designed to **subscribe to external stores** (non-React state sources) in a way that's compatible with concurrent rendering. It's prima...