node-on

Node-js EventEmitter helpers

Install

npm install node-on

`on`

(...events: string[]) => (callback: (val: any) => void) => (...emitters: EventEmitter[]) => () => void

import { on } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = on(
  'data',
  'end'    // events to listen
)(
  (value: any) => {} // your callback
)

const unsub = observer(
  e0,
  e1       // subscribe to emitters
) // return unsubscribe function

// unsubscribe
unsub()

`onEx`

(...events: string[]) => (callback: (val: {value: any, event: string, index: number, emitterIndex: number, emitter: EventEmitter}) => void) => (...emitters: EventEmitter[]) => () => void

import { onEx } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = onEx(
  'data',
  'end'    // events to listen
)(
  ({ value, event, index, emitterIndex, emitter }) => {} // your callback
)

const unsub = observer(e0, e1) // subscribe to emitters, return unsubscribe function

// unsubscribe
unsub()

`onceAll`

(...events: string[]) => (callback: (values: any[]) => void) => (...emitters: EventEmitter[]) => () => void

import { onceAll } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = onceAll(
  'data',
  'end'    // events to listen
)(
  (values: any[]) => {} // your callback
)

const unsub = observer(e0, e1) // subscribe to emitters, return unsubscribe function

// unsubscribe
unsub()

`onceAllEx`

(...events: string[]) => (callback: (val: { value: any, event: string, index: number, emitter: EventEmitter, emitterIndex: number }) => void) => (...emitters: EventEmitter[]) => () => void

import { onceAll } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = onceAll(
  'data',
  'end'    // events to listen
)(
  ({ value, event, index, emitter, emitterIndex }) => {} // your callback
)

const unsub = observer(e0, e1) // subscribe to emitters, return unsubscribe function

// unsubscribe
unsub()

`onceAllPromise`

(...events: string[]) => (...emitters: EventEmitter[]) => Promise<any[]>

import { onceAllPromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceAllPromise(
  'data', // events to listen
)(
  e0,
  e1
).then(([valueFromEmitter0, valueFromEmitter1]) => {
  // your callback
})

`onceAllExPromise`

(...events: string[]) => (...emitters: EventEmitter[]) => Promise<{ value: any, event: string, index: number, emitter: EventEmitter, emitterIndex: number }[]>

import { onceAllPromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceAllPromise(
  'data' // events to listen
)(
  e0,
  e1
).then(([emitterExValue0, emitterExValue1]) => {
  // your callback
})

`onceAllPromiseReject`

(rejectEvents: string[], resolveEvents: string[]) => (...emitters: EventEmitter[]) => Promise<any[]>

import { onceAllPromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceAllPromise(['error'], ['data'])(
  e0,
  e1
).then(([ valueFromEmitter0, valueFromEmitter1 ]) => {
  // your callback
}).catch((error: any) => {
  // your error handler
})

`onceAllExPromiseReject`

(rejectEvents: string[], resolveEvents: string[]) => (...emitters: EventEmitter[]) => Promise<{ value: any, event: string, index: number, emitter: EventEmitter, emitterIndex: number }[]>

import { onceAllPromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceAllPromise(['error'], ['data'])(
  e0,
  e1
).then(([ valueExFromEmitter0, valueExFromEmitter1 ]) => {
  // your callback
}).catch(({ value, event, index, emitterIndex, emitter }) => {
  // your error handler
})

`onceRace`

(...events: string[]) => (callback: (val: any) => void) => (...emitters: EventEmitter[]) => () => void

import { onceRace } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = onceRace(
  'data',
  'end'    // events to listen
)(
  (value: any) => {} // your callback
)

const unsub = observer(
  e0,
  e1        // subscribe to emitters
) // return unsubscribe function

// unsubscribe
unsub()

`onceRaceEx`

(...events: string[]) => (callback: (val: { value: any, event: string, index: number, emitterIndex: number, emitter: EventEmitter }) => void) => (...emitters: EventEmitter[]) => () => void

import { onceRace } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

const observer = onceRace(
  'data',
  'end'    // events to listen
)(
  ({ value: any, emitterIndex: number, emitter: EventEmitter }) => {} // your callback
)

const unsub = observer(
  e0,
  e1        // subscribe to emitters
) // return unsubscribe function

// unsubscribe
unsub()

`onceRacePromise`

(...events: string[]) => (...emitters: EventEmitter[]) => Promise<any>

import { onceRacePromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceRacePromise(
  'data',
  'end'    // events to listen
)(
  e0,
  e1       // subscribe to emitters
).then((value: any) => {
  // your callback
})

`onceRaceExPromise`

(...events: string[]) => (...emitters: EventEmitter[]) => Promise<{ value: any, event: string, index: number, emitterIndex: number, emitter: EventEmitter }>

import { onceRaceExPromise } from 'node-on'

// we have the following emitters
declare const e0: EventEmitter,
              e1: EventEmitter

onceRacePromiseEx(
  'data',
  'end'    // events to listen
)(
  e0,
  e1       // subscribe to emitters
).then(({ value, event, index, emitterIndex, emitter }) => {
  // your callback
})

`onceRacePromiseReject`