This article is a continuation of last week’s post on ES2017 Async-Await, detailing the updates of ES2017. Check out the ES2016 plus compatibility table for more information on the current browser support. Most likely, you will need a transpiler. Use […]

ES2017 Object and String Extensions


The ability to write asynchronous functions is a major update in ES2017. In order to understand this chapter, I suggest that you review the chapter on promises. What are asynchronous functions? Asynchronous functions are functions that return a promise. We […]

A Practical Introduction to ES2017 Async-Await


If you have read most of the blog posts of zsoltnagy.eu, you can conclude that most of the articles require at least some basic knowledge about JavaScript. The main exception is the JavaScript Basics category. This article is in the […]

Using JavaScript in 2018 – Experience and Opportunities



Exercise: Suppose the following tables are given in the form of arrays of objects: [crayon-5b4e44fb4d382650736848/] Translate the following SQL query using map, reduce, and filter: [crayon-5b4e44fb4d38e103254671/] You are not allowed to use loops, if statements, logical operators, or the ternary […]

Translating SQL Queries using Map-Reduce-Filter in JavaScript


Exercise: What is memoization? What are its benefits? What is the necessary condition for using memoization? Illustrate the benefits of memoization using an example. Remark: Expect these types of questions when bridging theory with practice. You need to know what […]

Memoization in JavaScript


Exercise: Create a stopwatch that counts down from a given number of seconds in the format mm:ss. Make it possible to start, pause, and reset the countdown. Make sure you can pass a callback function to the timer that is […]

JavaScript Tech Interview Exercise 16: Stopwatch




As some of my subscribers might already know, I was busy authoring a JavaScript course on microservices together with Packt Publishing. This kind of cooperation is always interesting, because there are fixed target dates to follow, and I tend to […]

An Introduction to Microservices




A regular expression is converted into code executed in a virtual machine. This virtual machine runs on the virtual machine of the host language or editor. Abstract models make us understand how regular expressions are executed. Although these models often […]

Visualizing Regex Execution using Finite State Machines