From: Michael Heerdegen <michael_heerdegen@web.de>
To: Tomas Hlavaty <tom@logand.com>
Cc: Heime <heimeborgia@protonmail.com>, help-gnu-emacs@gnu.org
Subject: Re: Advantage using mapc over dolist
Date: Wed, 04 Dec 2024 05:33:49 +0100 [thread overview]
Message-ID: <877c8gqd76.fsf@web.de> (raw)
In-Reply-To: <87r06por3q.fsf@neko.mail-host-address-is-not-set> (Tomas Hlavaty's message of "Mon, 02 Dec 2024 19:51:53 +0100")
Tomas Hlavaty <tom@logand.com> writes:
> > Had thought the mapc would be faster.
>
> mapc calls a function (length list) times, so unless the compiler is
> clever enough to optimize this call away, it will be "slower"
Of course the same argument would hold for `dolist'. You can rewrite
any `dolist' expression to an equivalent `mapc' call and vice versa.
Which one is faster can only be explained by looking at the
implementation of the language. In case of Emacs Lisp, `while' loops
are the most efficient way of looping, and `dolist' expands to `while'.
It could be the other way round for a different Emacs Lisp compiler.
Michael.
prev parent reply other threads:[~2024-12-04 4:33 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-01 23:31 Advantage using mapc over dolist Heime via Users list for the GNU Emacs text editor
2024-12-02 6:26 ` Tomas Hlavaty
2024-12-02 18:30 ` Heime via Users list for the GNU Emacs text editor
2024-12-02 20:41 ` Tomas Hlavaty
2024-12-02 20:50 ` Jean Louis
2024-12-02 21:21 ` Tomas Hlavaty
2024-12-02 21:41 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 6:13 ` Jean Louis
2024-12-03 7:36 ` Tomas Hlavaty
2024-12-03 19:24 ` Jean Louis
2024-12-03 20:04 ` Tomas Hlavaty
2024-12-03 20:09 ` Jean Louis
2024-12-03 20:12 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 20:24 ` Jean Louis
2024-12-02 20:56 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 19:26 ` Jean Louis
2024-12-03 19:39 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 14:11 ` Stefan Monnier via Users list for the GNU Emacs text editor
2024-12-03 14:48 ` Tomas Hlavaty
2024-12-03 16:31 ` Stefan Monnier
2024-12-03 17:00 ` Alfred M. Szmidt
2024-12-03 17:24 ` Stefan Monnier
2024-12-03 19:27 ` Tomas Hlavaty
2024-12-03 19:35 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 14:59 ` Tomas Hlavaty
2024-12-03 15:40 ` Tomas Hlavaty
2024-12-03 15:57 ` Tomas Hlavaty
2024-12-03 17:11 ` Eli Zaretskii
2024-12-03 17:33 ` Tomas Hlavaty
2024-12-03 17:40 ` Eli Zaretskii
2024-12-03 17:55 ` Tomas Hlavaty
2024-12-03 18:05 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 18:57 ` Alfred M. Szmidt
2024-12-03 19:06 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 20:15 ` Tomas Hlavaty
2024-12-04 5:37 ` Alfred M. Szmidt
2024-12-03 19:42 ` Jean Louis
2024-12-03 19:54 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 20:11 ` Jean Louis
2024-12-03 16:47 ` Stefan Monnier
2024-12-03 18:01 ` Heime via Users list for the GNU Emacs text editor
2024-12-03 20:05 ` Jean Louis
2024-12-03 20:35 ` Tomas Hlavaty
2024-12-03 23:29 ` Stefan Monnier
2024-12-04 0:57 ` Heime via Users list for the GNU Emacs text editor
2024-12-04 2:20 ` Stefan Monnier via Users list for the GNU Emacs text editor
2024-12-03 19:38 ` Jean Louis
2024-12-04 4:56 ` Michael Heerdegen via Users list for the GNU Emacs text editor
2024-12-02 6:59 ` Tassilo Horn
2024-12-02 10:12 ` Michael Heerdegen via Users list for the GNU Emacs text editor
2024-12-02 17:03 ` Heime via Users list for the GNU Emacs text editor
2024-12-02 18:51 ` Tomas Hlavaty
2024-12-02 20:17 ` Heime via Users list for the GNU Emacs text editor
2024-12-02 21:07 ` Tomas Hlavaty
2024-12-03 13:19 ` Tomas Hlavaty
2024-12-02 21:15 ` [External] : " Drew Adams
2024-12-02 21:58 ` Tomas Hlavaty
2024-12-02 22:42 ` Drew Adams
2024-12-03 5:49 ` Tomas Hlavaty
2024-12-03 20:08 ` Lazy functional programming [was: Advantage using mapc over dolist] Drew Adams
2024-12-03 21:17 ` Tomas Hlavaty
2024-12-04 4:33 ` Michael Heerdegen [this message]
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