From 37b125e7fa284b3afe0c6e78d42dd4ae3869040a Mon Sep 17 00:00:00 2001
From: waiting <1661926154@qq.com>
Date: Sun, 24 Sep 2017 16:56:34 +0800
Subject: [PATCH] fix: variable scope

---
 docs/async.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/docs/async.md b/docs/async.md
index 0954698..65cb443 100644
--- a/docs/async.md
+++ b/docs/async.md
@@ -505,8 +505,9 @@ function spawn(genF) {
   return new Promise(function(resolve, reject) {
     const gen = genF();
     function step(nextF) {
+      let next; 
       try {
-        var next = nextF();
+        next = nextF();
       } catch(e) {
         return reject(e);
       }