From 8ca2a1bf5b31adb924c778f289c5fcb0e006cf6a Mon Sep 17 00:00:00 2001
From: Brian Donovan <me@brian-donovan.com>
Date: Fri, 22 Oct 2010 14:41:31 -0700
Subject: [PATCH] IE uses an empty string as the value of an empty capture
 group.

---
 Objective-J/sprintf.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Objective-J/sprintf.js b/Objective-J/sprintf.js
index 82bf3c34c..9ad4723a5 100644
--- a/Objective-J/sprintf.js
+++ b/Objective-J/sprintf.js
@@ -62,7 +62,7 @@ exports.sprintf = function(format)
                 length          = subtokens[6],
                 specifier       = subtokens[7];
 
-            if (argIndex === undefined)
+            if (argIndex === undefined || argIndex === null || argIndex === "")
                 argIndex = arg++;
             else
                 argIndex = Number(argIndex);