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+## AsyncFunction
+
+JScript does not support the `async` keyword. So, Wilson JS uses the `AsyncFunction` class made by itself.
+
+### Examples
+
+```js
+var STD = require("lib/std");
+
+[5, 4, 3, 2, 1].forEach(function(x) {
+    new AsyncFunction(function() {
+        sleep(x * 1000);
+    }).run();
+});
+```