From 1899651aa16fd665893473c48c0e03a70021f30f Mon Sep 17 00:00:00 2001
From: Andrew Hyndman <ajhyndman@hotmail.com>
Date: Tue, 7 Jun 2016 20:01:48 +1000
Subject: [PATCH] Update documentation

---
 docs/rules/arrow-body-style.md | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/docs/rules/arrow-body-style.md b/docs/rules/arrow-body-style.md
index 25f3b5129b8..0efe4f0a2a7 100644
--- a/docs/rules/arrow-body-style.md
+++ b/docs/rules/arrow-body-style.md
@@ -1,10 +1,10 @@
 # Require braces in arrow function body (arrow-body-style)
 
-Arrow functions can omit braces when there is a single statement in the body. This rule enforces the consistent use of braces in arrow functions.
+Arrow functions have two syntactic forms for their function bodies.  They may be defined with a *block* body (denoted by curly braces) `() => { ... }` or with a single expression `() => ...`, whose value is implicitly returned.
 
 ## Rule Details
 
-This rule can enforce the use of braces around arrow function body.
+This rule can enforce or disallow the use of braces around arrow function body.
 
 ## Options
 
@@ -12,6 +12,7 @@ The rule takes one option, a string, which can be:
 
 * `"always"` enforces braces around the function body
 * `"as-needed"` enforces no braces where they can be omitted (default)
+* `"never"` enforces no braces around the function body (constrains arrow functions to the role of returning an expression)
 
 ### "always"
 
@@ -84,3 +85,30 @@ let foo = () => {
     // do nothing.
 };
 ```
+
+### "never"
+
+When the rule is set to `"never"` the following patterns are considered problems:
+
+```js
+/*eslint arrow-body-style: ["error", "never"]*/
+/*eslint-env es6*/
+
+let foo = () => {
+    return 0;
+};
+let foo = (retv, name) => {
+    retv[name] = true;
+    return retv;
+};
+```
+
+The following patterns are not considered problems:
+
+```js
+/*eslint arrow-body-style: ["error", "as-needed"]*/
+/*eslint-env es6*/
+
+let foo = () => 0;
+let foo = () => ({ foo: 0 });
+```