bug#56199: closed (hash table equality predicate [PATCH])

[GNU bug Tracking System]

Your message dated Sat, 25 Jun 2022 18:56:27 +0200
with message-id <2AD517D9-A9BC-44E2-A3DB-51AD84D29540@acm.org>
and subject line Re: bug#56199: hash table equality predicate [PATCH]
has caused the debbugs.gnu.org bug report #56199,
regarding hash table equality predicate [PATCH]
to be marked as done.

(If you believe you have received this mail in error, please contact
help-debbugs@gnu.org.)


-- 
56199: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=56199
GNU Bug Tracking System
Contact help-debbugs@gnu.org with problems

--- Begin Message --- Subject: hash table equality predicate [PATCH] Date: Fri, 24 Jun 2022 19:19:54 +0200

Recently[1] a predicate for structural equality was requested that also 
recurses through hash tables.
It showed that Emacs doesn't even come with a way of comparing hash tables. 
Third-party implementations exist but if the code quoted in [2] is 
representative, perhaps it would make sense to add a `hash-table-equal-p` 
predicate?
Even implemented entirely in Lisp it would be an order of magnitude faster (and 
actually correct).

The attached code is not without flaws but provides a rough starting point.
(This is not meant as a strong argument for or against adding it in the first 
place.)

hash-table-equal-p.diff
Description: Binary data

--

[1] https://lists.gnu.org/archive/html/emacs-devel/2022-06/msg00444.html
[2] https://lists.gnu.org/archive/html/emacs-devel/2022-06/msg00553.html

--- End Message ---

> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: bug#56199: hash table equality predicate [PATCH]
>
>
>
>
> Date: 
>
> Sat, 25 Jun 2022 18:56:27 +0200
>
>
>
>
> 24 juni 2022 kl. 20.21 skrev Lars Ingebrigtsen <larsi@gnus.org>:
>
> > I can't ever recall wanting to compare two hash tables for equality
> > (like, that's not what you use a hash table for)
>
> No, you're right -- it's better to wait until there is a concrete need for it.
>
>
>
> --- End Message ---