E:\IronPython-1.0-Beta1>IronPythonConsole IronPython 1.0.2190 (Beta) on .NET 2.0.50727.42 Copyright (c) Microsoft Corporation. All rights reserved. >>> def g(): ... yield 1 ... Traceback (most recent call last): Exception: Object reference not set to an instance of an object. >>> Seo Sanghyeon