zheksoon / dipole Goto Github PK

Hi,

Just wondering, why do you use a custom implementation of HashSet?

I noticed it says in your README, "ES3 compatibility - should work even in a very old browsers" - so maybe that's why?

Still, the standard Set is in all browsers since 6+ years, so I wonder.

Either way, what do you think about a "ponyfill" approach instead?

That is, make your HashSet constructor and methods compatible with standard Set methods, so that you can produce two different builds? e.g. two builds, one of them smaller (and probably faster) for modern browsers.

Hey,

This library is interesting as as state management solution for React/Preact - but I'm really interested in using this library to create a truly reactive UI library, one that doesn't diff virtual DOM nodes, along the lines of Sinuous.

I cobbled together a working prototype last night, and this was surprisingly easy:

https://codesandbox.io/s/reactive-dom-lol-rrtd4?file=/src/index.jsx

The problem is, this leaks listeners like crazy - if you make a few changes to the input value, and then toggle the checkbox, you can see the "LOL" messages piling up in the console. Reactions aren't getting garbage-collected, presumably because they internally reference the observables they're listening to.

From the documentation, I understand I'd have to manually destroy() the reactions to free them - which I've tried to do, but suddenly everything is much more complex than it seems on the surface, as I basically have to manually manage the whole create/update/destroy life-cycle using code.

I could be wrong, but I don't think S.js has this issue? Not sure.

I wonder if there would be something we can do with WeakMap to enable garbage-collection of reactions - or maybe avoid keeping subscriber references by decoupling their relations through a message bus or something?

I honestly don't understand the theory behind it all, I just know I like it. 😄

Is this something you're interested in at all, or is this mostly a state management library to you? 🙂

Will you explain a usage for this utility? I was trying to grok it. Thanks!

I was wondering about this line here:

What is arguments for?

As far as I can tell, arguments will be empty, since run() does not accept any arguments.

There are no calls to run() on a Reaction in user code, right?

Or is there a use-case where manager might pass arguments to run(), which would get forwarded?

As covered in the documentation, you have to manually .run() a reaction the first time:

const r = reaction(() => {  
    console.log(`Sum of ${a.get()} and ${b.get()} is ${sum.get()}`)  
})  
r.run()     // first run should be triggered manually  

The documentation doesn't really explain why that is?

The thing that puzzles me is, what do you actually have, if you haven't called the run method yet?

You don't really have a reaction yet - if it hasn't run the function, it doesn't know the function's dependencies, and so it can't actually react to anything yet.

When is an "inactive" reaction useful? Or why isn't the reaction automatically run the first time?

Thanks for this awesome lib! https://gist.github.com/mrjjwright/43d3ddf4830fb8d6bb3085b5652f9221