Q701. What is the output of below console statement with unary operator?
Let's take console statement with unary operator as given below, ```javascript console.log(+"Hello"); // NaN ``` The output of the above console log statement returns NaN...
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Q702. How do you handle 404 / Not Found routes?
React Router matches routes top-to-bottom/most-specific-first, so a catch-all route with `path="*"` placed last will match any URL that didn't match an earlier route — th...
Q703. Does javascript uses mixins?
JavaScript does not have built-in support for mixins as a formal language feature. However, developers commonly implement mixins using various patterns to enable code reu...
Q704. What are loaders, actions, and data APIs in modern React Router?
Starting with React Router v6.4, the library ships **data APIs** (`createBrowserRouter`, `loader`, `action`, `useLoaderData`, `useActionData`, `useFetcher`) that move dat...
Q705. Mixin Example using Object composition
```javascript // Define a mixin const canEat = { eat() { console.log("Eating..."); } }; const canWalk = { walk() { console.log("Walking..."); } }; const canRead = { read(...
Q706. How do query parameters work?
Query (search) parameters are the `?key=value&key2=value2` portion of a URL. Unlike route params (see [What are dynamic routes and what are route parameters?](#what-are-d...
Q707. Benefits
- Avoids deep inheritance hierarchies - Encourages composition over inheritance - Promotes reusable and modular code Modern JavaScript favors mixin alternatives like comp...
Q708. What is Concurrent Rendering? (Legacy)
The Concurrent rendering makes React apps to be more responsive by rendering component trees without blocking the main UI thread. It allows React to interrupt a long-runn...
Q709. What is a thunk function?
A thunk is just a function which delays the evaluation of the value. It doesn’t take any arguments but gives the value whenever you invoke the thunk. i.e, It is used not ...
Q710. Why should we not update the state directly?
If you try to update the state directly then it won't re-render the component. ```javascript //Wrong this.state.message = "Hello world"; ``` Instead use `setState()` meth...