From 49bb80f8a20c73ffb673aa8c68ad99bb0419d9a1 Mon Sep 17 00:00:00 2001
From: rmorshea <ryan.morshead@gmail.com>
Date: Fri, 4 Sep 2020 00:26:01 -0700
Subject: [PATCH] fix type annotation

---
 idom/core/hooks.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/idom/core/hooks.py b/idom/core/hooks.py
index dfe1786a5..ef5fd4203 100644
--- a/idom/core/hooks.py
+++ b/idom/core/hooks.py
@@ -125,7 +125,7 @@ def use_effect(
     """
     hook = current_hook()
     memoize = use_memo(args=args)
-    last_clean_callback = use_ref(None)
+    last_clean_callback: Ref[Optional[_EffectCleanFunc]] = use_ref(None)
 
     def add_effect(function: _EffectApplyFunc) -> None: