The labeled statement can be used with break or continue statements. It is prefixing a statement with an identifier which you can refer to. (more…)

Performance is an important criteria when choosing test-runner. Tests should pass as fast as possible to detect errors earlier, improve developer experience and reduce CI servers running time. In… (more…)

This is a debugging story of how to determine what event listener is calling event.preventDefault() or event.stopPropagation() or some other completely random thing which is not allowing your intended action. (more…)

I've got to do several things before my new book, Modern Front-End Development with Ruby on Rails and Puppies , is finished. It's currently ...

After large ES6 release, that took about 6 years (Dec 2009 – Jun 2015) to get standardized, TC39 committee has given notice of annual but smaller releases, starting with ECMAScript 2016 (ES7). The final feature set of ES8 hasn't been approved yet, as o...