unofficial mirror of emacs-devel@gnu.org 
 help / color / mirror / code / Atom feed
From: Sam Steingold <sds@gnu.org>
To: emacs-devel@gnu.org, "Mattias Engdegård" <mattiase@acm.org>
Subject: Re: lexicographic list comparison
Date: Mon, 12 Sep 2022 10:45:06 -0400	[thread overview]
Message-ID: <lzsfkwmz2l.fsf@3c22fb11fdab.ant.amazon.com> (raw)
In-Reply-To: <E79429C1-EBAA-4601-A818-1BDF6745B7B1@acm.org> ("Mattias Engdegård"'s message of "Sat, 10 Sep 2022 11:07:49 +0200")

> * Mattias Engdegård <znggvnfr@npz.bet> [2022-09-10 11:07:49 +0200]:
>
> 9 sep. 2022 kl. 21.27 skrev Sam Steingold <sds@gnu.org>:
>
>> What do you do when sorting a list of lists of numbers?
>
> Sigh deeply and write ad-hoc code for the nth time.

okay, so, I suppose, you find the `lexicographic-compare-lists' from TS
useful, right?

>> Or maybe sorting lists of lists is just such a rare op that no one has
>> ever encountered it before me?
>
> It would be useful to have a total ordering on Lisp values: for
> heterogeneous ordered collections, for simplifying multi-key sorting,
> for normalising unordered collections, etc.

I certainly have no intention of comparing strings with numbers &c.
My question was about a list of _homogeneous_ lists, and comparing to,
say, lists of numbers, is done lexicographically based on number
comparison.


-- 
Sam Steingold (https://aphar.dreamwidth.org/) on darwin Ns 10.3.2113
https://lastingimpactpsychology.com https://steingoldpsychology.com
https://www.peaceandtolerance.org/ https://www.memritv.org
When C++ is your hammer, everything looks like a thumb.



  parent reply	other threads:[~2022-09-12 14:45 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-09 19:27 lexicographic list comparison Sam Steingold
2022-09-10  9:07 ` Mattias Engdegård
2022-09-10  9:22   ` Emanuel Berg
2022-09-10  9:26   ` tomas
2022-09-12 14:45   ` Sam Steingold [this message]
2022-09-12 17:53     ` mattiase
2022-09-12 18:31       ` Stefan Monnier
2022-09-12 18:41         ` Sam Steingold
2022-09-12 19:32           ` Stefan Monnier
2022-09-12 18:35       ` Sam Steingold

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/emacs/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=lzsfkwmz2l.fsf@3c22fb11fdab.ant.amazon.com \
    --to=sds@gnu.org \
    --cc=emacs-devel@gnu.org \
    --cc=mattiase@acm.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).