[Python-Dev] cpython: Use cached builtins. (original) (raw)

Nick Coghlan ncoghlan at gmail.com
Thu Oct 3 13:05:39 CEST 2013

On 3 Oct 2013 06:00, "Victor Stinner" <victor.stinner at gmail.com> wrote:

I don't remember where, but I remember that I also saw things like "str=str, len=len, ...". So you keep the same name, but you use fast local lookups instead of slow builtin lookups.

functools uses the local binding trick in lru_cache as a speed hack (pretty sure it uses an underscore prefix, though).

However lru_cache is likely to end up being speed critical and it's binding local variables , so it's actually shifting a lot more work to compile time than merely trading a builtin lookup for a global lookup does.

For most code though, introducing that kind of complexity isn't worth the cost in readability.

Cheers, Nick.

Victor 2013/10/2 Antoine Pitrou <solipsis at pitrou.net>: > On Wed, 2 Oct 2013 18:16:48 +0200 (CEST) > serhiy.storchaka <python-checkins at python.org> wrote: >> http://hg.python.org/cpython/rev/d48ac94e365f >> changeset: 85931:d48ac94e365f >> user: Serhiy Storchaka <storchaka at gmail.com> >> date: Wed Oct 02 19:15:54 2013 +0300 >> summary: >> Use cached builtins. > > What's the point? I don't think it's a good idea to uglify the code if > there isn't a clear benefit. > > Regards > > Antoine. > > _> ________________________ > Python-Dev mailing list > Python-Dev at python.org > https://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: https://mail.python.org/mailman/options/python-dev/victor.stinner%40gmail.com

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