ovar wait_for

1 files changed, 12 insertions, 4 deletions

diff --git a/src/observable.ts b/src/observable.ts
index f00b845..15a1a2e 100644
--- a/src/observable.ts
+++ b/src/observable.ts
@@ -12,10 +12,8 @@ export class OVar<T> {
     }
 
     get value() { return this._value }
-    set value(v: T) {
-        this._value = v;
-        this.observers.forEach(o => o(v))
-    }
+    set value(v: T) { this._value = v; this.change() }
+    change() { this.observers.forEach(o => o(this._value)) }
 
     onchange(handler: (v: T) => unknown): () => void {
         this.observers.push(handler)
@@ -31,4 +29,14 @@ export class OVar<T> {
         this.onchange(v => uv.value = fn(v))
         return uv;
     }
+    wait_for(val: T) {
+        return new Promise<void>(r => {
+            const abort = this.onchangeinit(v => {
+                if (v == val) {
+                    r()
+                    abort()
+                }
+            })
+        })
+    }
 }