From: Emanuel Berg <incal@dataswamp.org>
To: help-gnu-emacs@gnu.org
Subject: unused lexical variable in `cl-loop'
Date: Tue, 27 Sep 2022 22:43:50 +0200 [thread overview]
Message-ID: <8735cclf95.fsf@dataswamp.org> (raw)
This code works but the byte-compiler says the lexical
variable 'num' is unused on the first two occasions it occurs
in the code.
;;; -*- lexical-binding: t -*-
;;
;; this file:
;; https://dataswamp.org/~incal/emacs-init/math.el
(require 'cl-lib)
(defun interval (&optional min max)
(interactive "nmin: \nnmax: ")
(or min (setq min 0))
(or max (setq max 9))
(unless (<= min max)
(error "Bogus interval") )
(cl-loop for i from min to max
with num = ()
collect i into num
finally return num) )
;; (interval 10 5)
;; (interval)
;; (interval 19 99)
;; Warning: Unused lexical variable `num'
;; Warning: Unused lexical variable `num'
I don't know if that makes sense, it doesn't look like it,
however it gave me an idea:
(defun interval (&optional min max)
(interactive "nmin: \nnmax: ")
(or min (setq min 0))
(or max (setq max 9))
(unless (<= min max)
(error "Bogus interval") )
(cl-loop for i from min to max collect i) )
and indeed that works just as well and there isn't a warning.
So that's good ... but why nothing happens with 'num' in the
first attempt I wonder?
--
underground experts united
https://dataswamp.org/~incal
next reply other threads:[~2022-09-27 20:43 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-27 20:43 Emanuel Berg [this message]
2022-09-28 10:58 ` unused lexical variable in `cl-loop' Michael Heerdegen
2022-09-28 12:40 ` Felix Dietrich
2022-09-30 22:59 ` Emanuel Berg
2022-10-01 15:10 ` Stefan Monnier via Users list for the GNU Emacs text editor
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=8735cclf95.fsf@dataswamp.org \
--to=incal@dataswamp.org \
--cc=help-gnu-emacs@gnu.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.
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).