ensure the fn can be GCed in once()

1 files changed, 2 insertions, 3 deletions

diff --git a/lib/internal/once.js b/lib/internal/once.js
index fabdffd..11678dc 100644
--- a/lib/internal/once.js
+++ b/lib/internal/once.js
@@ -1,8 +1,7 @@
 export default function once(fn) {
-    var called = false;
     return function () {
-        if (called) return;
-        called = true;
+        if (fn === null) return;
         fn.apply(this, arguments);
+        fn = null;
     };
 }