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Fibonacci Sequence In JavaScript
Fibonacci Sequence is a sequence of numbers in which each number is a sum of the previous two, starting with 0 and 1. The example sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, etc. It can be represented by the following formula...Read more
React Hooks: usePrevious
Retrieving the previous state of the component is a must in some special cases. While class-based components provide an easy and convenient way to do this via the componentDidUpdate() lifecycle hook, function components do not and you need to write custom...Read more
Replace All String Occurrences In JavaScript
Replacing all occurrences of a string is a fairly common task in JavaScript. I would not believe you if you said that you have never written any code to replace underscores with hyphens or vice versa. There are a few ways to do that...Read more
Git Stash Like A Pro
The developers work is often interrupted by requests to implement more important features or even to fix some critical bugs. This situation leads to stopping the development and switching to another task, but what if you didn't manage to complete the current work and you are not ready to...Read more
Error: 'yield' expression implicitly results in an 'any' type because its containing generator lacks a return-type annotation
Due to the fact that my article on How To Add Redux Saga With TypeScript To The React Application became popular, I've been asked one question a few times already. After finishing the tutorial, you expect to have built a fully working application using the mentioned technologies, but suddenly...Read more
Promise.any() And AggregateError In JavaScript
Nowadays, due to the increasing popularity of asynchronous programming, Promises have become an essential part of software engineer's daily routine. Promise is an object that produces a value in the future, which represents the result of an asynchronous operation. It has 3 states...Read more
3 Ways To Mock Axios In Jest
Every developer should know how to create a function that makes an API request, and how to test it properly. While creating such a function is a relatively simple task (if you use a good HTTP client, like Axios), testing it requires some effort. It's not always good practice to...Read more
Logical OR/AND/Nullish Assignments In JavaScript
The latest JavaScript specification, ECMAScript 2021, includes a lot of useful features, but the one we'll discuss today is Logical Assignment Operator, which is a combination of a logical operator (||, &&, ??) with an assignment (=)...Read more
Navigate To The Previous/Next Page In JavaScript
Redirecting users from one page to another is a very common operation in web applications. In most cases we know exactly which page the user should land on after clicking a link, but sometimes we don't. Imagine you are implementing a profile page that is accessible from both, page A and page B...Read more