Bugs item #1249615, was opened at 2005-08-01 14:54 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1249615&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Python Interpreter Core Group: Python 2.4 Status: Open Resolution: None Priority: 5 Submitted By: Hugh Gibson (hgibson50) Assigned to: Nobody/Anonymous (nobody) Summary: isinstance() fails depending on how modules imported Initial Comment: I have found an inconsistency with instance type checking dependent on how modules are imported. Using Windows 2000, Python 2.4.1. Source files are attached. Unzip preserving paths. To run, open a cmd window and set PythonPath to the location of the "system" folder. Run ServerRun.py. The program creates two class instances in two different modules, then calls a class function on one instance which takes as parameter the second instance. A call to isinstance to check if the parameter is of the correct class fails. If a parameter is passed to ServerRun.py then the class module is imported in a different way (specifying the path to the class) and the isinstance check succeeds. The output shows that before the call to the class function, an isinstance() call succeeds in both cases. There is obviously an easy fix in code, but I think that isinstance checking should not depend on how modules are imported. And, if I am using an incorrect module import sequence, that sequence should be disallowed. Sample output (also showing Windows 2000 version) is: Microsoft Windows 2000 [Version 5.00.2195] (C) Copyright 1985-2000 Microsoft Corp. C:\system\server>set pythonpath=c:\system C:\system\server>serverrun ServerRun: oNew.__class__ == <class 'Stream.Stream.CElement'> Stream.CElement == <class 'Stream.Stream.CElement'> isinstance(oNew, Stream.CElement) == True AddField(): oNew.__class__ == <class 'Stream.Stream.CElement'> CElement == <class 'server.Stream.Stream.CElement'> isinstance(oNew, CElement) == False C:\system\server>serverrun 1 ServerRun: oNew.__class__ == <class 'server.Stream.Stream.CElement'> Stream.CElement == <class 'server.Stream.Stream.CElement'> isinstance(oNew, Stream.CElement) == True AddField(): oNew.__class__ == <class 'server.Stream.Stream.CElement'> CElement == <class 'server.Stream.Stream.CElement'> isinstance(oNew, CElement) == True C:\system\server> ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1249615&group_id=5470 _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
