doc: update setup

liximomo · liximomo · commit 4c55a58911f3 · 2019-06-25T18:05:08.000+08:00
diff --git a/README.md b/README.md
@@ -119,23 +119,25 @@ After installing the plugin you can use the new [function API](#API) to compose
 
 A new component option, `setup()` is introduced. As the name suggests, this is the place where we use the function-based APIs to setup the logic of our component. `setup()` is called when an instance of the component is created, after props resolution. The function receives the resolved props as its first argument.
 
-
-Example:
+The second argument provides a `context` object which exposes a number of properties that were previously exposed on this in 2.x APIs.
 
 ```js
 const MyComponent = {
   props: {
     name: String
   },
-  setup(props) {
-    console.log(props.name)
+  setup(props, context) {
+    console.log(props.name);
+    // context.attrs
+    // context.slots
+    // context.refs
+    // context.emit
+    // context.parent
+    // context.root
   }
 }
 ```
 
-> **`this` is not available inside `setup()`.**
-
-
 ## value
 
 ▸ **value**(value: *`any`*): [`Wrapper`][Wrapper]
diff --git a/README.zh-CN.md b/README.zh-CN.md
@@ -123,15 +123,19 @@ Vue.use(plugin)
 
 `setup()` 中不可以使用 `this` 访问当前组件实例, 我们可以通过 `setup` 的第二个参数 `context` 来访问 vue2.x API 中实例上的属性。
 
-Example:
-
 ```js
 const MyComponent = {
   props: {
     name: String
   },
-  setup(props) {
-    console.log(props.name)
+  setup(props, context) {
+    console.log(props.name);
+    // context.attrs
+    // context.slots
+    // context.refs
+    // context.emit
+    // context.parent
+    // context.root
   }
 }
 ```
