Re: FFmpeg considering GIT

From: Jan Hudec <bulb@ucw.cz>
Date: May 10, 2007, 16:52 UTC
Message-ID: <20070510165215.GA13060@efreet.light.src>
In-Reply-To: <e5bfff550705100420x63b365f7x526c1d58d9d5c761@mail.gmail.com>

On Thu, May 10, 2007 at 13:20:02 +0200, Marco Costalba wrote:

Show 31 quoted lines

> On 5/9/07, Jan Hudec <bulb@ucw.cz> wrote:
> >On Wed, May 09, 2007 at 23:09:25 +0200, Fredrik Kuivinen wrote:
> >> I have used PyQt for some smaller projects (notably Hgct, a no longer
> >> developed
> >> commit tool for git and Mercurial. See
> >> http://repo.or.cz/w/hgct.git?a=tree). For me
> >> PyQt has worked very well. The python interface to Qt is more or less a
> >> direct
> >> translation of the C++ interface, so the excellent documentation troll
> >> tech provides
> >> for Qt can be used when developing with PyQt as well.
> >>
> >> I have never seen the segfaulting you mention. Maybe my programs have 
> >been
> >> too
> >> small to trigger that bug...
> >
> >It's not about size of the programs. It's about having to be careful not to
> >refer to widgets inside eg. dialog box from outside and close that dialog
> >box.
> 
> In Qt all the classes that ineriths from QObject are memory managed,
> to be more clear
> you can say that one class is "child" of another class (always
> ineritherd from QObject) that becames the parent.
> 
> When you delete the parent, all his children are deleted too, this is
> a (big) feature to avoid
> missing free() calls for resources created with mallocs() , (well, in
> C++ we say 'delete' for resources created by 'new' but the concept is
> more or less the same).

I know well how it works. And while it is definitely a nice feature in C++ (though it can't beat well done reference-counting smart pointers as Gtkmm has), it is a gross misfeature in any dynamic language.

And no, I am not objecting to existence of that system -- it's useful in C++. What I say is, that the PyQt bindings are buggy because it completely fails to make this feature compatible with python memory management - python program should not be able to segfault the interpreter no matter how buggy that program is.

-- 
						 Jan 'Bulb' Hudec <bulb@ucw.cz>