43 lines
844 B
JavaScript
43 lines
844 B
JavaScript
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import log from './log';
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class EventEmitter {
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constructor() {
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this.events = {};
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}
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addEventListener(event, listener) {
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if (typeof this.events[event] !== 'object') {
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this.events[event] = [];
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}
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this.events[event].push(listener);
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return listener;
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}
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removeListener(event, listener) {
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if (typeof this.events[event] === 'object') {
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const idx = this.events[event].indexOf(listener);
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if (idx > -1) {
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this.events[event].splice(idx, 1);
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}
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if (this.events[event].length === 0) {
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delete this.events[event];
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}
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}
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}
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emit(event, ...args) {
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if (typeof this.events[event] === 'object') {
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this.events[event].forEach((listener) => {
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try {
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listener.apply(this, args);
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} catch (e) {
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log('EventEmitter.emit', e);
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}
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});
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}
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}
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}
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const events = new EventEmitter();
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export default events;
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