[ python-Bugs-1721812 ] A subclass of set doesn't always have __init__ called.

[SourceForge.net]

Bugs item #1721812, was opened at 2007-05-19 14:03
Message generated for change (Comment added) made by gbrandl
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1721812&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 Library
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: David Benbennick (dbenbenn)
>Assigned to: Raymond Hettinger (rhettinger)
Summary: A subclass of set doesn't always have __init__ called.

Initial Comment:
Consider the following code:

>>> class foo(set):
...     def __init__(self, iter):
...         print "foo.__init__"
...         set.__init__(self, iter)
... 
>>> x = foo([1,2])
foo.__init__
>>> y = foo([2,3])
foo.__init__
>>> x & y
foo([2])

As you can see, the foo.__and__ method creates a new foo object without calling foo.__init__.

The problem is in Objects/setobject.c:make_new_set().

----------------------------------------------------------------------

>Comment By: Georg Brandl (gbrandl)
Date: 2007-05-19 16:11

Message:
Logged In: YES 
user_id=849994
Originator: NO

Wasn't that fixed some time ago?

@OP: what Python version do you use?

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1721812&group_id=5470