Learning Leptos: "To create_effect(), or Not To create

Learning Leptos: "To create_effect(), or Not To create_effect()?"

Рет қаралды 9,673

Жыл бұрын

This video answers the common question: When should I use create_effect? When should I not use create_effect?
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Пікірлер: 19

@irlshrek Жыл бұрын

dude youre a machine! Thanks for everything youre doing!

@hitmanpete1 Жыл бұрын

Good job Greg! I learned stuff today ☺️

@JR-wu3rx 10 ай бұрын

thank you for the video Greg! Please do more. As a beginner in Leptos, it is helpful to get further context and examples in addition to what the book provides.

@emjizone Жыл бұрын

Thanks. This makes much clearer what are the distinct purposes of "signals" and "effets", what they are meant for.

@jaysistar2711 Жыл бұрын

This video is very informative on not just create_effect, but effects in a reactive system in general, both fine and course grained.

@tommycard4569 Жыл бұрын

This was such a well presented video and very insightful keep up the great work

@bonsairobo 8 ай бұрын

"Do people read docs, idk" The Leptos book sent me here lol

@JReuben111 2 ай бұрын

this framework is insanely powerful, almost a paradigm shift.

@bohdanivanchenko5262 Жыл бұрын

Thanks for the explanation of how create_effect works 🤗

@peterhayman Жыл бұрын

great presentation, sounds best to avoid calling set_signal inside an effect

@Mr_Yeah Жыл бұрын

14:55 Exactly, that's what I thought the whole time you coded the memoization. 😅

@climatechangedoesntbargain9140 Жыл бұрын

What would you do if you need an effect for doing a side effect that in the end provides some information which you want to get into the reactive system, i.e. pass to a signal?

@gbjxc Жыл бұрын

I think it depends… if it’s some kind of async action where a signal changes, you do something in response, and some time later that returns a new value you want in a signal, then an effect is reasonable (or create_resource or create_action) This also avoids the synchronous gotchas in that Show example where you can’t reason about the order it’s rendering. If it’s synchronous then it sounds like the second signal could be derived.

@sergesolkatt Жыл бұрын

❤️

@tenthlegionstudios1343 Жыл бұрын

Is this unsub resub pattern still true with effects in the latest leptos? I know that you were in the stream when milo and ryan were going over some of the algorithm optimizations milo had done in reactively. And looking into the leptos source code, I can see some of the same wording/patterns. AFAIK, solidjs doesnt follow this full unsub resub pattern and it is tracked in another way - but I could be wrong. I am also not sure if these patterns directly apply when using rust instead of being forced to use JS. Great video btw

@verified_tinker1818 Жыл бұрын

How could this be written without the unwrap() at all? unwrap_or() would cause unnecessary re-rendering, right?

@gbjxc Жыл бұрын

Do you mean on the NodeRef::get() calls? It's safe to .unwrap() or .expect() there in an event listener - they are filled during the `view` macro itself - but if you're really unwrap averse you could do something like match (first(), last(), use_last()) { (Some(first), Some(last), Some(use_last)) => ... _ => {} } The other unwraps are coming from a `use_context` that I know I provided, and from a user's code that was buggy! If you mean the unwrap in the user code then yes, a safe version of this would've been to use .unwrap_or(), but I still wouldn't recommend the "write to a signal from an effect" approach because it adds the overhead of creating an extra signal and extra effect.