Initial commit

src/main/modules/observable.ts

@@ -0,0 +1,36 @@
+import { observable } from '@trpc/server/observable';
+
+type Func<T> = (arg: T) => void;
+
+abstract class Observable<T> {
+	private _listeners: Func<T>[] = [];
+
+	protected abstract _value: T;
+
+	protected _notifyObservers(v = this._value) {
+		this._listeners = this._listeners.filter(l => {
+			try {
+				l(v);
+				return true;
+			} catch {
+				return false;
+			}
+		});
+	}
+
+	observe() {
+		return observable<T>(e => {
+			e.next(this._value);
+			this._listeners.push(e.next);
+			return () => {
+				this._listeners = this._listeners.filter(v => v !== e.next);
+			};
+		});
+	}
+
+	clearObservers() {
+		this._listeners = [];
+	}
+}
+
+export default Observable;