concurrently
Version:
Run commands concurrently
25 lines (24 loc) • 864 B
JavaScript
Object.defineProperty(exports, "__esModule", { value: true });
exports.fromSharedEvent = void 0;
const rxjs_1 = require("rxjs");
const sharedEvents = new WeakMap();
/**
* Creates an observable for a specific event of an `EventEmitter` instance.
*
* The underlying event listener is set up only once across the application for that event emitter/name pair.
*/
function fromSharedEvent(emitter, event) {
let emitterEvents = sharedEvents.get(emitter);
if (!emitterEvents) {
emitterEvents = new Map();
sharedEvents.set(emitter, emitterEvents);
}
let observable = emitterEvents.get(event);
if (!observable) {
observable = (0, rxjs_1.fromEvent)(emitter, event).pipe((0, rxjs_1.share)());
emitterEvents.set(event, observable);
}
return observable;
}
exports.fromSharedEvent = fromSharedEvent;
;