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Limitations

Web Worker​

Before you start using this hook, I suggest you read the Web Worker documentation.

Remember that your web worker function fn must be a function without local dependencies, which does not produce side-effects.

warning
  • The web worker don't have access to the document, and window object
  document.querySelectorAll('#demoId'); // not allowed!!
  window.navigator // not allowed!!
warning
  • While the worker is running you cannot call it again, until it's finished, or until you kill it. To get around this you can create two or more "instances" of the hook
  const [sort1] = useWorker(sort, { timeout: 10000 });
  const [sort2] = useWorker(sort, { autoTerminate: false });
  const [sort3] = useWorker(sort);
warning
  • The web worker cannot returns a function because the response is serialized.
  const fn = () => {
    return () => 1 + 2 // not allowed!!
  }

  const fn = () => {
    const sum = 1 + 2
    return sum; // allowed!!
  }
warning

Web Workers are limited by the available CPU and memory

Is there a way to determine the number of available CPU cores in JavaScript? Yes using navigator.hardwareConcurrency

navigator.hardwareConcurrency