Brian Quinlan <br...@sweetapp.com> added the comment: Antoine Pitrou wrote: > Antoine Pitrou <pit...@free.fr> added the comment: > >> I think that this linearization is probably more useful: >> >> MyClass -> io.FileIO -> MyMixin -> IOBase > > But why not simply: > > MyClass -> MyMixin -> io.FileIO -> IOBase > > ? > Is there something I'm missing that prevents you from doing this?
No, doing this is trivial. But shouldn't it be up to the implementor of MyClass to decide whether MyMixin or io.FileIO methods are evaluated first? >> I'm not trying to change the ABC unification at all - and if I did then >> there is a bug in my code. I just think that the immediate parent class >> of _pyio.FileIO should be _pyio.IOBase (just like _io.FileIO has >> _io.IOBase as an immediate parent). That will make the Python and C >> class hierarchies completely consistent within themselves. > > I understand, but that's at the price of an otherwise useless > indirection layer, which will also make _pyio even slower that it > already is :-) Maybe I misunderstand the purpose of _pyio. The Python 3.1 says that its purpose is for experimentation. For experimentation, having a Python implementation where you can add methods and change behavior (though perhaps not in as deep as way is if this class were completely written in Python) is useful. It is also useful for the behavior of the Python implementation to match that of the C implementation as closely as possible - this patch makes the inheritance graph for _pyio.FileIO more consistent. I, for example, want to add a sync() method to FileIO that will call fsync() on the file's file descriptor. With this change, I have a place to plug in that change in Python and I can write the C implementation when I have the Python implementation right. Cheers, Brian ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue5700> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
