From: Tassilo Horn <tsdh@gnu.org>
To: Stefan Monnier <monnier@IRO.UMontreal.CA>
Cc: Michael Heerdegen <michael_heerdegen@web.de>, emacs-devel@gnu.org
Subject: Re: pcase-dolist
Date: Fri, 10 Jul 2015 16:44:42 +0200 [thread overview]
Message-ID: <87vbdsm5r9.fsf@gnu.org> (raw)
In-Reply-To: jwvpp41dtks.fsf-monnier+emacs@gnu.org
Stefan Monnier <monnier@IRO.UMontreal.CA> writes:
>> Yes, if you want to pick the first two elements of a list with 2 or
>> more elements, you should use `(,w ,x . ,_). I see that the above is
>> slightly more convenient and concise but I'd value consistency more.
>
> But that does not match the usual uses of "tuples represented as
> lists", where it's customary to use (A B) when the remaining fields
> are all nil (since (car nil) returns nil and (nth 5 '(1 2)) also
> returns nil rather than signaling an error) and where it's also
> customary to ignore any additional element.
Yes, but those don't have pcase in their name. If that wouldn't be the
case with `pcase-let' I would not complain at all.
Hm, when you said that a better name for `pcase-dolist' was `dolist',
wouldn't `let(*)' be a better name for `pcase-let(*)', too? It would be
very useful to be able to destructure in usual lets (like, e.g., in
Clojure). I think there are gazillion of occurrences of
(let* ((this-and-that (foo ...))
(this (car this-and-that))
(that (cdr this-and-that)))
...)
AFAICS, the only thing that `pcase-let' is lacking is the ability to
introduce locals without providing a value, e.g.,
(let ((x 1) b c) ...)
but that shouldn't be too hard to add, no?
Bye,
Tassilo
next prev parent reply other threads:[~2015-07-10 14:44 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-08 12:20 pcase-dolist Michael Heerdegen
2015-07-08 13:54 ` pcase-dolist Stefan Monnier
2015-07-08 17:32 ` pcase-dolist Michael Heerdegen
2015-07-08 18:26 ` pcase-dolist Tassilo Horn
2015-07-08 21:27 ` pcase-dolist Stefan Monnier
2015-07-09 6:05 ` pcase-dolist Tassilo Horn
2015-07-09 9:55 ` pcase-dolist Thierry Volpiatto
2015-07-09 10:17 ` pcase-dolist Tassilo Horn
2015-07-09 12:19 ` pcase-dolist Thierry Volpiatto
2015-07-09 13:34 ` pcase-dolist Tassilo Horn
2015-07-09 13:40 ` pcase-dolist Thierry Volpiatto
2015-07-09 19:26 ` pcase-dolist Stefan Monnier
2015-07-09 20:27 ` pcase-dolist Michael Heerdegen
2015-07-10 18:51 ` pcase-dolist Stefan Monnier
2015-10-12 11:27 ` pcase-setq (was: pcase-dolist) Michael Heerdegen
2015-10-12 11:54 ` pcase-setq Michael Heerdegen
2015-10-12 12:01 ` pcase-setq (was: pcase-dolist) Nicolas Petton
2015-10-12 12:36 ` pcase-setq Michael Heerdegen
2015-10-12 12:49 ` Semantic of pcase `seq' and `map' patterns (was: pcase-setq) Michael Heerdegen
2015-10-12 13:41 ` Semantic of pcase `seq' and `map' patterns Michael Heerdegen
2015-10-12 13:55 ` Nicolas Petton
2015-10-12 14:02 ` Michael Heerdegen
2015-10-17 12:21 ` Michael Heerdegen
2015-10-17 13:31 ` Nicolas Petton
2015-10-12 13:50 ` Semantic of pcase `seq' and `map' patterns (was: pcase-setq) Nicolas Petton
2015-10-13 0:59 ` pcase-setq Stefan Monnier
2015-10-13 13:52 ` pcase-setq Michael Heerdegen
2015-10-13 14:02 ` pcase-setq Michael Heerdegen
2015-10-13 15:52 ` pcase-setq Michael Heerdegen
[not found] ` <jwvfv1eboo8.fsf-monnier+emacs@gnu.org>
[not found] ` <87d1wh36as.fsf@web.de>
2015-10-14 15:49 ` pcase-setq Stefan Monnier
2015-07-10 14:44 ` Tassilo Horn [this message]
2015-07-10 19:04 ` pcase-dolist Stefan Monnier
2015-07-08 19:44 ` pcase-dolist Artur Malabarba
2015-07-08 20:50 ` pcase-dolist Michael Heerdegen
-- strict thread matches above, loose matches on Subject: below --
2014-07-11 10:35 pcase-dolist Sebastian Wiesner
2014-07-11 13:47 ` pcase-dolist Stefan Monnier
2014-07-11 13:50 ` pcase-dolist Sebastian Wiesner
2014-07-11 14:14 ` pcase-dolist Stefan Monnier
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