1 files changed, 19 insertions, 0 deletions
diff --git a/src/modules/observable.js b/src/modules/observable.js
new file mode 100644
index 0000000..e4f6797
--- /dev/null
+++ b/src/modules/observable.js
@@ -0,0 +1,19 @@
+const observers = {};
+
+export const Observable = Object.freeze({
+  notify: (event, data) => {
+    observers[event].forEach((observer) => observer(data))
+  },
+
+  subscribe: (event, func) => {
+    (observers[event] ??= []).push(func);
+  },
+
+  unsubscribe: (event, func) => {
+    [...observers[event] || []].forEach((observer, index) => {
+      if (observer === func) {
+        observers[event].splice(index, 1);
+      }
+    });
+  },
+});