Fix bound functions in IE8

Author: jridgewell

underscore.js

@@ -701,17 +701,18 @@
     if (nativeBind && func.bind === nativeBind) return nativeBind.apply(func, slice.call(arguments, 1));
     if (!_.isFunction(func)) throw new TypeError('Bind must be called on a function');
     var args = slice.call(arguments, 2);
-    return function bound() {
+    var bound = function() {
       return executeBound(func, bound, context, this, args.concat(slice.call(arguments)));
     };
+    return bound;
   };
 
   // Partially apply a function by creating a version that has had some of its
   // arguments pre-filled, without changing its dynamic `this` context. _ acts
   // as a placeholder, allowing any combination of arguments to be pre-filled.
   _.partial = function(func) {
     var boundArgs = slice.call(arguments, 1);
-    return function bound() {
+    var bound = function() {
       var position = 0, length = boundArgs.length;
       var args = Array(length);
       for (var i = 0; i < length; i++) {
@@ -720,6 +721,7 @@
       while (position < arguments.length) args.push(arguments[position++]);
       return executeBound(func, bound, this, this, args);
     };
+    return bound;
   };
 
   // Bind a number of an object's methods to that object. Remaining arguments