In the left year, there was an ECMAScript 2015 standard (informally ES6) which strongly changed what we got used to. There was a mass of new opportunities which in fact represent a modern superset of the language trying to solve the existing problems. Class, let, const, pointer functions … the developer who did not see the code written on ES6 not at once earlier will guess that before it, in fact, old kind JS.
There is a mass of the fine articles devoted to the modern standard. In the same post I want to show that modern JS when it is necessary to solve an essential problem can offer us. For example, to congratulate all on New Year.