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| export default class Emitter {
| constructor () {
| this._events = Object.create(null)
| }
|
| on (event, fn) {
| const vm = this
| if (Array.isArray(event)) {
| for (let i = 0, l = event.length; i < l; i++) {
| vm.on(event[i], fn)
| }
| } else {
| (vm._events[event] || (vm._events[event] = [])).push(fn)
| }
| return vm
| }
|
| emit (event, ...args) {
| const vm = this
| const callbacks = vm._events[event]
| if (callbacks) {
| const cbs = callbacks.slice(0)
| for (let i = 0, l = cbs.length; i < l; i++) {
| cbs[i].apply(vm, args)
| }
| }
| return vm
| }
| }
|
|
