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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Dmitry Gutov <dgutov@yandex.ru>
Cc: Oleh Krehel <o.krehel@tue.nl>, emacs-devel@gnu.org
Subject: Re: [PATCH] What's the quickest way to contribute?
Date: Tue, 13 Jan 2015 14:24:50 -0500	[thread overview]
Message-ID: <jwvppai4har.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <54B4FE6E.4070600@yandex.ru> (Dmitry Gutov's message of "Tue, 13 Jan 2015 14:15:58 +0300")

>> I think algorithmically, it's equivalent (both are O(N), basically).
> On some inputs, `cl-remove-if-not' could save on memory churn (less consing
> in the process), if the result list is small. Or if there's nothing to
> remove: it will simply return the original list.

Yes, they don't have quite the same efficiency both in terms of number
of instructions and memory use.
Still makes no difference "algorithmically" (i.e. still O(N)).

And my guess is still that in practice it will be a wash (even for
specially crafted benchmarks, I'd expect the performance to be very
similar, based on my past experience trying to use compiler-macros to
turn mapcar into dolist).


        Stefan



  reply	other threads:[~2015-01-13 19:24 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-08 17:59 [PATCH] What's the quickest way to contribute? Oleh Krehel
2015-01-08 18:48 ` Eli Zaretskii
2015-01-08 19:04   ` Samer Masterson
2015-01-08 19:13     ` Dmitry Gutov
2015-01-09  0:01     ` Richard Stallman
2015-01-13  2:57 ` Dmitry Gutov
2015-01-13  5:10   ` Stefan Monnier
2015-01-13 11:15     ` Dmitry Gutov
2015-01-13 19:24       ` Stefan Monnier [this message]
2015-01-13 13:46     ` Oleh Krehel
2015-01-13 19:32       ` Stefan Monnier

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