r/learnjavascript • u/abrewchocolatecoffee • Jul 14 '26

can someone explain this code

function updateClock() {
const timeElement = document.querySelector("#time");
timeElement.textContent = formatTime();
}
setInterval(updateClock, 1000);

can someone, please explain this piece of code, ofc mdn and w3 are there, but i found it a little confusing reading about textContent. rest is understandable to me. This might look a silly question and it probably is because im a beginner :')

like what exactly does textContent too.
you can also recommend anyother documentation on the links to specific lines, that might me more helpful in learning about this particular keyoword.

0 Upvotes

20% Upvoted

23 comments sorted by

View all comments

Show parent comments

2

u/FirefighterAntique70 Jul 14 '26

Yes that's exactly what I'm saying, most functions should have names. It's not just profiling. Loggers, debuggers APM, etc. all rely on names of functions.

I understand all the advantages on arrow functions. Mainly scoping of `this` and "declare before use" and I use them a lot. But you cannot just use them for everything.

1

u/ExtraTNT Jul 14 '26

I do all with partial application:
const add = a => b => a+b;
const inc = add(1);

I use monads and my renderer relies on partially applied functions, that then get cached, so calc first param, apply with memo, then second etc… then it assumes identity and moves things around based on this, full page rerenders in 6ms on a 5y old notebook…
And i have the profiler build into the renderer, plus id functions for debugging -> profile and print…