import { Parallel } from 'parallel-transform-web'

// a stream that yields random numbers, forever!
const randomNumbers = new ReadableStream({ pull: controller => controller.enqueue(Math.random() * 10) })
// run up to 10 transforms concurrently
const concurrency = 10
// identity transform that adds a short delay
const transformer = n => new Promise(resolve => setTimeout(() => resolve(n), n))
// parallelized transform stream
const delayer = new Parallel(concurrency, transformer)
// writable stream that just logs whatever is written to it
const logger = new WritableStream({ write: n => console.log(n) })

await randomNumbers.pipeThrough(delayer).pipeTo(logger)