Ticket #2803: faster-map.diff

core.js

@@ -1185 +1185 @@
     },
 
     map: function( elems, callback ) {
-        var ret = [];
+        var ret = [], value;
 
         // Go through the array, translating each of the items to their
         // new value (or values).
         for ( var i = 0, length = elems.length; i < length; i++ ) {
-            var value = callback( elems[ i ], i );
+            value = callback( elems[ i ], i );
 
-            if ( value !== null && value != undefined ) {
-                if ( value.constructor != Array )
-                    value = [ value ];
-
-                ret = ret.concat( value );
-            }
+            if ( value != null )
+                ret[ ret.length ] = value;
         }
 
-        return ret;
+        return ret.concat.apply( [], ret );
     }
 });