docs(generator): edit generator

ruanyf · ruanyf · commit 461d3edae8e1 · 2018-01-30T14:59:18.000+08:00
diff --git a/docs/generator.md b/docs/generator.md
@@ -1076,6 +1076,7 @@ function* g() {
 }
 
 let obj = g();
+obj.next();
 obj.a // undefined
 ```
 
