Q141. What is the purpose of double exclamation?
The double exclamation or negation(!!) ensures the resulting type is a boolean. If it was falsey (e.g. 0, null, undefined, etc.), it will be false, otherwise, it will be ...
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Q142. What are the exceptions on React component naming?
The component names should start with an uppercase letter but there are few exceptions to this convention. The lowercase tag names with a dot (property accessors) are sti...
Q143. What is the purpose of the delete operator?
The delete operator is used to delete the property as well as its value. ```javascript var user = { firstName: "John", lastName: "Doe", age: 20 }; delete user.age; consol...
Q144. Is it possible to use async/await in plain React?
Yes, you can use `async/await` in plain React, as long as your JavaScript environment supports ES2017+. Nowadays most modern browsers and build tools support ES2017+ vers...
Q145. What is typeof operator?
You can use the JavaScript typeof operator to find the type of a JavaScript variable. It returns the type of a variable or an expression. ```javascript typeof "John Abrah...
Q146. What are the common folder structures for React?
There are two common practices for React project file structure. 1. **Grouping by features or routes:** One common way to structure projects is locate CSS, JS, and tests ...
Q147. What is undefined property?
The undefined property indicates that a variable has not been assigned a value, or declared but not initialized at all. The type of undefined value is undefined too. ```j...
Q148. What are the popular packages for animation?
In modern React application development, animating components smoothly requires specialized libraries that handle component mount/unmount lifecycles and GPU-accelerated t...
Q149. What is null value?
The value null represents the intentional absence of any object value. It is one of JavaScript's primitive values. The type of null value is object. You can empty the var...
Q150. What is the benefit of styles modules?
It is recommended to avoid hard coding style values in components. Any values that are likely to be used across different UI components should be extracted into their own...