On Sat, 18 May 2013 06:37:54 -0700 Eli Bendersky <eli...@gmail.com> wrote: > Great PEP, I would really like to see this happen as it defines much saner > semantics for finalization than what we currently have. One small question > below: > > > This PEP proposes to turn CI disposal into the following sequence (new > > steps are in bold): > > > > 1. Weakrefs to CI objects are cleared, and their callbacks called. At > > this point, the objects are still safe to use. > > > > 2. **The finalizers of all CI objects are called.** > > > > 3. **The CI is traversed again to determine if it is still isolated. > > If it is determined that at least one object in CI is now reachable > > from outside the CI, this collection is aborted and the whole CI > > is resurrected. Otherwise, proceed.** > > > > Not sure if my question is the same as Armin's here, but worth a try: by > saying "the CI is traversed again" do you mean the original objects from > the CI as discovered earlier, or is a new scan being done? What about a new > object entering the CI during step (2)? I.e. the original CI was A->B->A > but now one of the finalizers created some C such that B->C and C->A adding > it to the connected component?
It is the original CI which is traversed. If a new reference is introduced into the reference chain, the traversal in step 3 will decide to resurrect the CI. This is not necessarily a problem, since the next GC collection will try collecting again. > Reading your description in (3) strictly it says: in this case the > collection is aborted. This CI will be disposed next time collection is > run. Is this correct? Yup. Regards Antoine. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
