From: Stefan Monnier <monnier@iro.umontreal.ca>
To: emacs-devel@gnu.org
Subject: Re: Why is there no `until' in elisp?
Date: Tue, 16 Oct 2018 17:28:28 -0400 [thread overview]
Message-ID: <jwvwoqhzis8.fsf-monnier+gmane.emacs.devel@gnu.org> (raw)
In-Reply-To: 87murdu6to.fsf@portable.galex-713.eu
> [0] such as: (defmacro until (test &rest body) (declare (indent 1))
> `(while (not ,test) ,@body))
I like `until`. As a matter of fact, I think `until` is more important
than `while` for the following reason: it should not behave like the one
you have above but rather like:
(defmacro until (test &rest body)
(let (res)
(while (not (setq res ,test)) ,@body)
res))
While `while` doesn't have much else to return than nil, `until` does
have a useful value to return, which is the non-nil value that caused it
to exit.
Stefan
next prev parent reply other threads:[~2018-10-16 21:28 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-16 17:42 Why is there no `until' in elisp? Garreau, Alexandre
2018-10-16 19:16 ` Eric Abrahamsen
2018-10-16 19:31 ` Garreau, Alexandre
2018-10-16 20:23 ` Eric Abrahamsen
2018-10-16 23:00 ` Garreau, Alexandre
2018-10-19 15:28 ` Stefan Monnier
2018-10-16 21:28 ` Stefan Monnier [this message]
2018-10-17 0:12 ` Garreau, Alexandre
2018-10-17 2:04 ` Stefan Monnier
2018-10-17 9:14 ` Garreau, Alexandre
2018-10-17 15:06 ` Stefan Monnier
2018-10-17 16:51 ` Garreau, Alexandre
2018-10-19 15:34 ` Stefan Monnier
2018-10-19 18:08 ` Garreau, Alexandre
2018-10-17 8:04 ` Yuri Khan
2018-10-17 9:23 ` Garreau, Alexandre
2018-10-17 9:46 ` Yuri Khan
2018-10-17 11:06 ` Garreau, Alexandre
2018-10-17 17:50 ` Paul Eggert
2018-10-17 21:15 ` Garreau, Alexandre
2018-10-17 21:35 ` Paul Eggert
2018-10-17 21:49 ` Garreau, Alexandre
2018-10-17 22:33 ` Paul Eggert
2018-10-17 22:54 ` Garreau, Alexandre
2018-10-17 12:41 ` Elias Mårtenson
2018-10-17 15:03 ` Stefan Monnier
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