Is it true that checking for refcount == 1 is enough? What if a user wrote:
args = (compute_integer(), 5) # give away args to someone int.__iadd__(*args) here `args[0]` still has refcount=1 because only `args` owns this integer. On Fri, Sep 1, 2017 at 4:19 PM, Jelle Zijlstra <jelle.zijls...@gmail.com> wrote: > > > 2017-09-01 13:05 GMT-07:00 Chris Barker <chris.bar...@noaa.gov>: > >> On Thu, Aug 31, 2017 at 5:12 PM, Antoine Pitrou <solip...@pitrou.net> >> wrote: >> >>> I'm skeptical there are some programs out there that are limited by the >>> speed of PyLong inplace additions. >>> >> >> indeed, but that could be said about any number of operations. >> >> My question is -- how can the interpreter know if it can alter what is >> supposed to be an immutable in-place? If it's used only internally to a >> function, the it would be safe, but how to know that? >> > I believe Catalin's implementation checks if the object's refcount is 1. > If that is the case, it is safe to mutate it. > >> >> -CHB >> >> >> >> -- >> >> Christopher Barker, Ph.D. >> Oceanographer >> >> Emergency Response Division >> NOAA/NOS/OR&R (206) 526-6959 voice >> 7600 Sand Point Way NE (206) 526-6329 fax >> Seattle, WA 98115 (206) 526-6317 main reception >> >> chris.bar...@noaa.gov >> >> _______________________________________________ >> Python-Dev mailing list >> Python-Dev@python.org >> https://mail.python.org/mailman/listinfo/python-dev >> Unsubscribe: https://mail.python.org/mailman/options/python-dev/jelle. >> zijlstra%40gmail.com >> >> > > _______________________________________________ > Python-Dev mailing list > Python-Dev@python.org > https://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: https://mail.python.org/mailman/options/python-dev/ > joe%40quantopian.com > >
_______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
