From 3143f2a791e5ebbe785785436a1eaf8b9413653e Mon Sep 17 00:00:00 2001
From: Bruno Windels <bruno@windels.cloud>
Date: Fri, 7 May 2021 13:06:20 +0200
Subject: [PATCH] also make an observable version of a retained value

---
 src/observable/ObservableValue.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/observable/ObservableValue.js b/src/observable/ObservableValue.js
index 3fbfe463..8a433444 100644
--- a/src/observable/ObservableValue.js
+++ b/src/observable/ObservableValue.js
@@ -94,6 +94,18 @@ export class ObservableValue extends BaseObservableValue {
     }
 }
 
+export class RetainedObservableValue extends ObservableValue {
+    constructor(initialValue, freeCallback) {
+        super(initialValue);
+        this._freeCallback = freeCallback;
+    }
+
+    onUnsubscribeLast() {
+        super.onUnsubscribeLast();
+        this._freeCallback();
+    }
+}
+
 export function tests() {
     return {
         "set emits an update": assert => {