From d8ab2f87c1705bff4f212cfb6d00ee4770abc1e1 Mon Sep 17 00:00:00 2001
From: Simon Sapin <simon.sapin@exyr.org>
Date: Thu, 6 Nov 2014 15:34:09 -0800
Subject: [PATCH] Add example impl in CLike docs. Fix 13752.

---
 src/libcollections/enum_set.rs | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/src/libcollections/enum_set.rs b/src/libcollections/enum_set.rs
index 93dbb7e8b207..1acdaef9c91c 100644
--- a/src/libcollections/enum_set.rs
+++ b/src/libcollections/enum_set.rs
@@ -43,7 +43,27 @@ impl<E:CLike+fmt::Show> fmt::Show for EnumSet<E> {
     }
 }
 
-/// An interface for casting C-like enum to uint and back.
+/**
+An interface for casting C-like enum to uint and back.
+A typically implementation is as below.
+
+```{rust,ignore}
+#[repr(uint)]
+enum Foo {
+    A, B, C
+}
+
+impl CLike for Foo {
+    fn to_uint(&self) -> uint {
+        *self as uint
+    }
+
+    fn from_uint(v: uint) -> Foo {
+        unsafe { mem::transmute(v) }
+    }
+}
+```
+*/
 pub trait CLike {
     /// Converts a C-like enum to a `uint`.
     fn to_uint(&self) -> uint;