[Python-Dev] Borrowed and Stolen References in API

[Antoine Pitrou]

On Thu, 5 May 2011 19:17:30 +0200
"Amaury Forgeot d'Arc" <amauryfa at gmail.com> wrote:

> 2011/5/5 Guido van Rossum <guido at python.org>:
> > Seems you're in agreement with this. IMO when references are borrowed
> > it is not very interesting. The interesting thing is when calling a
> > function *steals* a reference. The other important thing to know is
> > whether the caller ends up owning the return value (if it is an
> > object) or not. I *think* you can tell the latter from the +1 for the
> > return value; but the former (whether it steals a reference) is
> > unclear from the data given. There's even an XXX comment about this in
> > the file:
> >
> > # XXX NOTE: the 0/+1/-1 refcount information for arguments is
> > # confusing!  Much more useful would be to indicate whether the
> > # function "steals" a reference to the argument or not.  Take for
> > # example PyList_SetItem(list, i, item).  This lists as a 0 change for
> > # both the list and the item arguments.  However, in fact it steals a
> > # reference to the item argument!
> 
> Should we change this file then?
> And only list functions that don't follow the usual conventions.

+1

Regards

Antoine.