From a5454d6972063a65bfa0611a237663f19e509856 Mon Sep 17 00:00:00 2001
From: Noah Sloan <iamnoah+github@gmail.com>
Date: Tue, 8 Dec 2009 14:24:44 -0600
Subject: [PATCH] cache hasOwnProperty

---
 underscore.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/underscore.js b/underscore.js
index 81898d4af..da40afaa8 100644
--- a/underscore.js
+++ b/underscore.js
@@ -391,10 +391,11 @@
   /* ------------------------- Object Functions: ---------------------------- */
 
   // Retrieve the names of an object's properties.
+  var hasOwnProperty = Object.prototype.hasOwnProperty;
   _.keys = function(obj) {
     if(_.isArray(obj)) return _.range(0, obj.length);
     var keys = [];
-    for (var key in obj) if (Object.prototype.hasOwnProperty.call(obj, key)) keys.push(key);
+    for (var key in obj) if (hasOwnProperty.call(obj, key)) keys.push(key);
     return keys;
   };