From 27d8ea05a257af534579c5ecef79d45781f3a8f0 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Sat, 10 May 2014 13:48:26 -0700
Subject: [PATCH] core: Implement and export the try! macro

This is used quite extensively by core::fmt
---
 src/libcore/macros.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/libcore/macros.rs b/src/libcore/macros.rs
index 11b74aaffe9..a04d93260c5 100644
--- a/src/libcore/macros.rs
+++ b/src/libcore/macros.rs
@@ -59,3 +59,9 @@ macro_rules! assert(
 macro_rules! debug_assert(
     ($($arg:tt)*) => (if cfg!(not(ndebug)) { assert!($($arg)*); })
 )
+
+/// Short circuiting evaluation on Err
+#[macro_export]
+macro_rules! try(
+    ($e:expr) => (match $e { Ok(e) => e, Err(e) => return Err(e) })
+)