Update arc.rs

克雷 · 克雷 · commit 3ece65700413 · 2015-01-07T11:16:41.000+08:00
diff --git a/src/liballoc/arc.rs b/src/liballoc/arc.rs
@@ -37,7 +37,7 @@
 //!
 //! let five = Arc::new(5i);
 //!
-//! for i in range(0u, 10) {
+//! for _ in range(0u, 10) {
 //!     let five = five.clone();
 //!
 //!     Thread::spawn(move || {
