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Discussion on: Building a Reactive Library from Scratch

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Replies for: Yeah, the example works - I guess I have trust issues with plain JS without types. I've seen too much JS that "works", but not for the right reason...

 
peerreynders profile image
peerreynders •

I still can't make sense of the types.

Sometimes clarity comes from the chosen names.

Change #1:

// A Dependency has many different Subscribers depending on it
// A particular Subscriber has many Dependencies it depends on
type Dependency = Set<Subscriber>;
type Subscriber = {
  execute(): void;
  dependencies: Set<Dependency>;
};
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Change #2:

  const subscriptions: Dependency = new Set();
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Change #3:

function cleanup(running: Subscriber) {
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Change #4:

  const running: Subscriber = {
    execute,
    dependencies: new Set(),
  };
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mindplay profile image
Rasmus Schultz • 
// A Dependency has many different Subscribers depending on it
// A particular Subscriber has many Dependencies it depends on
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Yes! This is what the article/video/example was missing. Thank you! 😀🙏