main-event

Example

import { TypedEventEmitter } from 'main-event'
import type { TypedEventTarget } from 'main-event'

interface EventTypes {
  'test': CustomEvent<string>
}

const target = new TypedEventEmitter<EventTypes>()

// it's a regular EventTarget
console.info(target instanceof EventTarget) // true

// register listeners normally
target.addEventListener('test', (evt) => {
  // evt is CustomEvent<string>
})

// @ts-expect-error 'derp' is not in the event map
target.addEventListener('derp', () => {})

// use normal dispatchEvent method
target.dispatchEvent(new CustomEvent('test', {
  detail: 'hello'
}))

// use type safe dispatch method
target.safeDispatchEvent('test', {
  detail: 'world'
})

// report listener count
console.info(target.listenerCount('test')) // 0

// event emitters can be used purely as interfaces too
function acceptTarget (target: TypedEventTarget<EventTypes>) {
  // ...
}
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