Q721. What are the benefits higher order functions?
A **Higher-Order Function (HOF)** in JavaScript is a function that either accepts one or more functions as arguments, or returns a function as its result (leveraging firs...
Technical Question Bank · Peer-Reviewed
Job Interview Questions and Answers Directory
Search and filter frequently asked interview questions across technical, programming, and behavioral domains. Tailor your interview preparation by difficulty for freshers or experienced developers (780 available).
Active:
Tag: js ×
Q722. How do you create polyfills for map, filter and reduce methods?
The polyfills for array methods such as map, filter and reduce methods can be created using array prototype. 1. **map:** The built-in `Array.map` method syntax will be he...
Q723. What is the difference between map and forEach functions?
Both map and forEach functions are used to iterate over an arrays but there are some differences in their functionality. 1. **Returning values:** The `map` method returns...
Q724. Give an example of statements affected by automatic semicolon insertion?
The javascript parser will automatically add a semicolon while parsing the source code. For example, the below common statements affected by Automatic Semicolon Insertion...
Q725. What are the event phases of a browser?
There are 3 phases in the lifecycle of an event propagation in JavaScript, 1. **Capturing phase:** This phase goes down gradually from the top of the DOM tree to the targ...
Q726. What are the real world use cases of proxy?
Proxies are not used in regular day to day JavaScript work but they enabled many exciting programming patterns. Some of the real world use cases are listed below, 1. Vue3...
Q727. What are hidden classes?
Since JavaScript is a dynamic programming language, you can add or remove properties and methods from objects on the fly at runtime. This nature of JavaScript increases t...
Q728. What is inline caching?
Inline caching is an optimization technique based on the observation that repeated calls to same function tends to occur on same type of objects. The V8 compiler stores a...
Q729. What are the different ways to execute external scripts?
There are three different ways to execute external scripts, 1. async: The script is downloaded in parallel to parsing the page, and executed as soon as it is available ev...
Q730. What is Lexical Scope?
Lexical scope is the ability for a function scope to access variables from the parent scope. ```js function x(){ var a=10; function y(){ console.log(a); // will print a ,...