add comment

niulingyun · niulingyun · commit a2eb39a3b00f · 2017-09-16T21:53:26.000+08:00
diff --git a/src/Coroutine/Sleep.php b/src/Coroutine/Sleep.php
@@ -10,6 +10,10 @@
 
 class Sleep extends Base
 {
+    /**
+     * sleep的时间
+     * @var int
+     */
     public $__sleepTime;
 
     /**
