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Discussion on: Building a Reactive Library from Scratch

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goldeli profile image
缪宇 • • Edited

Hey Ryan, great article, I benefit a lot from it, thank you so much.

Q: Why use context stack?

I replaced the context stack, and it words fine. full code

let context = ""
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const read = () => {
    const running = context;
    if (running) subscribe(running, subscriptions);
    return value;
};
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const execute = () => {
    cleanup(running);
    context = running;
    try {
      fn();
    } finally {
      context = "";
    }
};
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ryansolid profile image
Ryan Carniato •

Nested reactivity. Generally you can nest effects or derivations inside themselves. This is important to how Solid renders but I suppose wasn't needed for this simple example.

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goldeli profile image
缪宇 •

I nested effects, but it also works fine. full code

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ryansolid profile image
Ryan Carniato • • Edited

If you try to subscribe after the inner effect it doesn't track. Change the example to:

createEffect(() => {
  createEffect(() => {
    log("value is ", value());
  });
  log("name is ", name());
});
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Keep in mind this is just a simple approximation. I don't actually use an array in my libraries and instead just store the out context and then restore it.