         			var row:Array = rows[row_idx+1];
         			var key_values:Array = new Array(key_column_indices.length);
 
-        			for (var idx:int = 0; idx < key_column_indices.length; idx++)
+        			for (idx = 0; idx < key_column_indices.length; idx++)
         			{
         				key_values[idx] = row[key_column_indices[idx]];
         			}

					jsonCache.getJsonObject(data[VARIABLES_LINK], function(result:Object):void
						{
							data.cache = result;
							var concepts:Object = {};
							/* Build a hierarchy out of 'concepts', roughly speaking, tables. */
							for (var key:String in result.variables)
							{
								if (key == "for" || key == "in") continue;
								var column:Object = result.variables[key];

								concepts[concept_name][key] = metadata;
							}

							for (key in concepts)
							{
								children.push(createConceptNode({
									variables: concepts[key],
