Home/ Questions/Q 37859
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-10T14:37:01+00:00

While answering Static class variables in Python I noticed that PythonWin PyWin32 build 209.2

  • 0

While answering Static class variables in Python

I noticed that PythonWin PyWin32 build 209.2 interpreter seems to evaluate twice?

PythonWin 2.5 (r25:51908, Mar  9 2007, 17:40:28) [MSC v.1310 32 bit (Intel)] on win32. Portions Copyright 1994-2006 Mark Hammond - see 'Help/About PythonWin' for further copyright information. >>> class X: ...     l = [] ...     def __init__(self): ...         self.__class__.l.append(1) ...          >>> X().l [1, 1] >>>

while the python interpreter does the right thing

C:\>python ActivePython 2.5.0.0 (ActiveState Software Inc.) based on Python 2.5 (r25:51908, Mar  9 2007, 17:40:28) [MSC v.1310 32 bit (Intel)] on win32 Type 'help', 'copyright', 'credits' or 'license' for more information. >>> class X: ...   l = [] ...   def __init__(self): ...     self.__class__.l.append(1) ... >>> X().l [1] >>>
Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. My guess is as follows. The PythonWin editor offers autocomplete for an object, i.e. when you type myobject. it offers a little popup of all the availble method names. So I think when you type X(). it’s creating an instance of X in the background and doing a dir or similar to find out the attributes of the object.

    So the constructor is only being run once for each object but to give you the interactivity it’s creating objects silently in the background without telling you about it.

    • 0