another big refactor

src/lib/observable/ObservableValue.hx

@@ -0,0 +1,28 @@
+package lib.observable;
+
+using tink.CoreApi;
+
+class ObservableValue<T> implements Observable<T> {
+	private var value:T;
+	private var callbacks:CallbackList<T> = new CallbackList();
+
+	public function new(value:T) {
+		this.value = value;
+	}
+
+	public function set(value:T) {
+		if (value != this.value) {
+			this.value = value;
+			callbacks.invoke(value);
+		}
+	}
+
+	public function get():T {
+		return value;
+	}
+
+	public function subscribe(callback:Callback<T>):CallbackLink {
+		callback.invoke(value);
+		return callbacks.add(callback);
+	}
+}