Application and Events

Does anyone know if Foundry's Application (or the browser itself) does anything magical to clean up after events registered on the html elements created by that application?

I've a vague memory that this is one of the things jquery was good for, and that unless you explicitly clean up manually registered events, you've got potential for a memory leak. I don't have any good sources for that and I'm pretty fuzzy on browser memory and performance matters, but I wondered if anyone more knowledgable than me has taken a look at such things.

🧵

there's not like some element.unregisterAllListners ?

Alright next question, I've done some reading about garbage collection in the browser and the thing that stuck with me is something to the effect of:

The memory of the element can't be cleaned up because there's still an event listener registered to it

Full disclosure, i have about 5% confidence in that memory

So the browser is smart enough to know that when an element is nuked via replacing innerHtml, its old event listeners are useless and thus can be nuked as well?

hypothesis: it would only be noticable if the events were registered without jquery because, to my limited understanding, that's one of jquery's claims to fame

i'm failing pretty hard at googling this...

I tried this a long time ago and what I saw concerned me, but I realized I had no real knowledge of what I was looking at and wasn't feeling frisky that week 😛

So it sounds like...

1. element created
2. events are registered on that element
3. time passes

4. innerHtml change causes old element to be destroyed
5. old element being destroyed destroys event listeners on said element
6. event listeners being destroyed means that the callbacks are no longer referenced

Therefore... everything is garbage collectable.

7. repeat from 1.

The whole "no references to those elements" is what trips me up. Because sometimes I necessarily have a reference to that element in my event handler callback... So like... I do still have a reference there, but it's kinda circular?

maybe some day i'll learn more about profiling and do that experiment again ¯\_(ツ)_/¯

interesting

thanks @ghost 🙂

@Calego gave LeaguePoints™ to @ghost (#4 • 634)

that feels expensive

tfw you just want to have your cake and eat it too

makes sense, plus they're probably smart enough to wait until its likely that they can run without disruption

very interesting

gotchya, thanks
that explains why there's not a million 'gotchyas' blog articles talking about this interaction

@Calego gave LeaguePoints™ to @Mouse0270 (#27 • 97)