[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Raymond Hettinger added the comment: I'm going to decline this suggestion. Antoine is right that this is a can of worms best less closed. Likewise, Richard pointed out that there is potential to break existing code. FWIW, the existence of super() does not imply that all existing classes

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Antoine Pitrou added the comment: Multi-inheritance is tricky to get right, both for the class being extended and the class extending it. The APIs mentioned here were never designed for multiple inheritance and aren't supposed to support it. Your use case would probably be better served by

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Changes by Serhiy Storchaka : -- assignee: -> rhettinger ___ Python tracker ___

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Serhiy Storchaka added the comment: The _Verbose class and verbose arguments for threading classes and functions were removed in issue13550. Thus this is 2.7-only issue now. -- nosy: +haypo versions: -Python 3.3, Python 3.4 ___ Python tracker

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Serhiy Storchaka added the comment: Raymond, what do you think? -- ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue16572 ___ ___ Python-bugs-list

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Changes by Serhiy Storchaka storch...@gmail.com: -- stage: - patch review versions: +Python 3.4 ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue16572 ___

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Éric Araujo added the comment: Adding Raymond, who thinks super is super, to the nosy list. http://rhettinger.wordpress.com/2011/05/26/super-considered-super/ -- nosy: +eric.araujo, rhettinger ___ Python tracker rep...@bugs.python.org

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Changes by Daniel Urban urban.dani...@gmail.com: -- nosy: +daniel.urban ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue16572 ___ ___

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

New submission from Thomas Chiroux: when using multi-inheritance and super() in __init__(), super() tries to run each constructor once. For this to work correctly, it is needed to call super() in each constructor, including for Classes directly inherited from object. The sample below does not

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Serhiy Storchaka added the comment: Can you please provide a diff in unified format? I don't see any super() in Lib/threading.py. -- nosy: +serhiy.storchaka ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue16572

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Thomas Chiroux added the comment: updated diff file, unified format -- Added file: http://bugs.python.org/file28151/diff_unified_threading.py_2.7.patch ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue16572

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Richard Oudkerk added the comment: The patch is liable to break programs which explicitly call base constructors because the constructor will be called more than once. It also assumes that the __init__() method of all base classes should be called with no arguments (other than self). That is

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Thomas Chiroux added the comment: That's right. Lets consider this 'patch' was more for illustrating my example (like: this kind of modification may work) than to add directly into python core module... (which i'm not capable of) But I think the problem remains: do you agree that Classes

[issue16572] Bad multi-inheritance support in some libs like threading or multiprocessing

Richard Oudkerk added the comment: But I think the problem remains: do you agree that Classes should include a super() call in their __init__ ? No, I don't. I think super() is an attractive nuisance which is difficult to use correctly in an __init__() method, except in the trivial case