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Comment by wonger_ | Hacker News Reader

I love how the map automatically updates based on the places typed in the editor. A great visual aid to a text-based workflow.

I got confused by this comment though:

  > To determine when to re-render, “reactive” frameworks like Svelte and Solid track property access using Proxies, whereas “immutable” frameworks like React rely on object identity.

I thought React was just as reactive as all the other JS frameworks, and that the state/setState code would look similar.

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Author here! Maybe I could have worded that better — basically, when you call setState in React, it compares the identities of the new state and old state to determine whether to re-render. Svelte and Solid use “signals” to automatically determine when to re-render, with the drawback that you’re no longer interacting with the “raw” value but a Proxy. But neither way would be able to detect Yjs mutating its internal state; you’re correct that even in React you would need some sort of wrapper code “tricking” it into re-rendering when appropriate.

I’ve enjoyed using https://syncedstore.org/docs/ as such wrapper code for Yjs in React. They have a Svelte lib too, haven’t tried it.

Great article, congrats on releasing!

I haven't worked frontend in a long time but just from reading that snippet I would assume React does a `obj===obj` (identity) comparison for state update under the hood, while Svelte/Solid are doing a Proxy trap on the accessors like `parent.obj =` would result in an intercept fn being called when you hit that 'obj' access. Proxy being a little more complicated to reason about and setup in totality but a lot more powerful and flexible.

React is not "reactive" according to the classic definition, but even the creator of Solid.js thinks that doesn't really matter.

https://dev.to/this-is-learning/how-react-isn-t-reactive-and...

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