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Package detail

@calebboyd/semaphore

calebboyd21.4kMIT1.3.1TypeScript support: included

Simple promise based counting semaphore

readme

Semaphore

Naive resource management / concurrency primitive

npm i @calebboyd/semaphore

Example

import { Semaphore } from '@calebboyd/semaphore'
import { something } from './somewhere'

function doSomeWork () {
  const lock = new Semaphore(10)
  while(something.isTrue) {
    lock.acquire().then(x => () => {
      something.work().then(lock.release)
    })    
  }
}

The semaphore will only allow 10 locks to be aquired at a time. This limits the concurrency of the asyncronous function something.work to 10

API:

export class Semaphore {
  constructor (count: number) {}
  acquire(): Promise<void>
  release(): void
}

License

MIT