From e95fd6a1a7124be0128d73e68453cd3ec15a415e Mon Sep 17 00:00:00 2001
From: HerringtonDarkholme <HerringtonDarkholme@users.noreply.github.com>
Date: Thu, 26 Oct 2017 13:33:42 +0800
Subject: [PATCH 1/2] Recommend return type annotation

---
 src/v2/guide/typescript.md | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/src/v2/guide/typescript.md b/src/v2/guide/typescript.md
index e7d9b61f00..36413c6059 100644
--- a/src/v2/guide/typescript.md
+++ b/src/v2/guide/typescript.md
@@ -139,3 +139,38 @@ var vm = new Vue({
   myOption: 'Hello'
 })
 ```
+
+## Annotating Return Type
+
+Vue's type definition is prone to [circular reference](https://github.com/Microsoft/TypeScript/issues/12846#issuecomment-270296195) of `this`.
+Annotating return type is highly recommended to avoid such error.
+
+```ts
+import Vue, { VNode } from 'vue'
+
+const Component = Vue.extend({
+  data() {
+    return {
+      msg: 'Hello'
+    }
+  },
+  methods: {
+    // need annotation due to `this` in return type
+    greet(): string {
+      return this.msg + ' world'
+    }
+  },
+  computed: {
+    // need annotation
+    greeting(): string {
+      return this.greet() + '!'
+    }
+  },
+  // `createElement` is inferred, but `render` needs return type
+  render(createElement): VNode {
+    return createElement('div', this.greeting)
+  }
+})
+```
+
+If you find type inference or member completion doesn't work, you can try annotating method return type.

From da1a1412f8ddc0149b625c00611c30ab972fb361 Mon Sep 17 00:00:00 2001
From: Herrington Darkholme <nonamesheep1@gmail.com>
Date: Thu, 26 Oct 2017 23:07:20 +0800
Subject: [PATCH 2/2] make explanation clear, thank @DanielRosenwasser

---
 src/v2/guide/typescript.md | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/v2/guide/typescript.md b/src/v2/guide/typescript.md
index 36413c6059..8dddc833d4 100644
--- a/src/v2/guide/typescript.md
+++ b/src/v2/guide/typescript.md
@@ -140,10 +140,10 @@ var vm = new Vue({
 })
 ```
 
-## Annotating Return Type
+## Annotating Return Types
 
-Vue's type definition is prone to [circular reference](https://github.com/Microsoft/TypeScript/issues/12846#issuecomment-270296195) of `this`.
-Annotating return type is highly recommended to avoid such error.
+Because of the circular nature of Vue's declaration files, TypeScript may have difficulties inferring the types of certain methods.
+For this reason, you may need to annotate the return type on methods like `render` and those in `computed`.
 
 ```ts
 import Vue, { VNode } from 'vue'
@@ -173,4 +173,5 @@ const Component = Vue.extend({
 })
 ```
 
-If you find type inference or member completion doesn't work, you can try annotating method return type.
+If you find type inference or member completion isn't working, annotating certain methods may help address these problems.
+Using the `--noImplicitAny` option will help find many of these unannotated methods.