Category: JavaScript


Diving into functions. Passing by reference is a lie!

Functions are one of the most basic features of JavaScript. Have you ever wondered how exactly do they work? After all, they are just a special kind of objects. If you are curious, dig into them with me in this article! The basics of functions Speaking practically, a function is a subprogram that can be called […]


Keeping your dependencies in order when using NPM.

Mastering your tools as a developer is a very important thing. One of them is Node Package Manager – and quite a crucial one for a JavaScript developer. Having a better understanding how dependencies work will improve your workflow greatly and help to avoid many problems both for you and your fellow developers. Today we will cover […]

JavaScript Regex

Regex course – part one. Basic concepts.

This entry is part 1 of 4 in the Regex course

Regular expressions (regex) are sequences of characters defining a search pattern. Since it can be extremely useful in programmers everyday life, it was implemented into JavaScript. In this series of articles, I will show you how it works and what are its real-life usages. Hopefully, by the end of this part of the course, you […]


Demystifying generators. Implementing async/await.

Generators are a new feature introduced in ES6, and as I’ve promised in the article about async/await last week, we will cover them today. Iterators In JavaScript an iterator is an object that provides a next() method which returns the next item in the sequence. The first concept to understand here is the iterator. You might […]


Explaining async/await. Creating dummy promises.

Back in the days, we used callbacks. Then, we were blessed with promises. The journey does not stop there, though. ES7 introduced us to a new way of handling asynchronous calls: async/await. Feel free to read my other articles if you would like to know more about async in general, or callbacks and promises. The purpose […]


[1] + [2] – [3] === 9!? Looking into assembly code of coercion.

Variable values have certain types. In fact, you can cast a value of one type to the other. If you do it explicitly, it is type casting (also called explicit coercion). If it happens in the background when you are trying to perform an operation on types that do not match, it is called coercion (sometimes referred to […]


Scopes in JavaScript. Different types of variable declarations.

You can think of a scope as of a wrapper that contains all the variables and a reference to the parent scope. What does that mean and what should we watch out for when dealing with it? Let’s find out! How scopes work When we try to access a variable in our code, the interpreter […]