[Python-Dev] Borrowed and Stolen References in API

Amaury Forgeot d'Arc amauryfa at gmail.com
Thu May 5 19:17:30 CEST 2011

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.

But I'm sure that there are external tools which already use refcounts.dat
in its present format.

Amaury Forgeot d'Arc

More information about the Python-Dev mailing list