kefir/src/primary/from-node-callback.js

Reactive Programming library for JavaScript inspired by Bacon.js and RxJS with focus on high performance and low memory usage

import stream from './stream'

export default function fromNodeCallback(callbackConsumer) {
  let called = false

  return stream(function(emitter) {
    if (!called) {
      callbackConsumer(function(error, x) {
        if (error) {
          emitter.error(error)
        } else {
          emitter.emit(x)
        }
        emitter.end()
      })
      called = true
    }
  }).setName('fromNodeCallback')
}