Class Semaphore

A simple Semaphore implementation which provides a limited queue for ensuring proper concurrency.

Param: max

The maximum number of tasks which are allowed concurrently.

Example: Using a Semaphore

// Some async function that takes time to execute
function fn(x) {
  return new Promise(resolve => {
    setTimeout(() => {
      console.log(x);
      resolve(x);
    }, 1000));
  }
};

// Create a Semaphore and add many concurrent tasks
const semaphore = new Semaphore(1);
for ( let i of Array.fromRange(100) ) {
  semaphore.add(fn, i);
}
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