From: Arash Esbati <arash@gnu.org>
To: carlmarcos--- via Users list for the GNU Emacs text editor
<help-gnu-emacs@gnu.org>
Cc: tomas@tuxteam.de, carlmarcos@tutanota.com
Subject: Re: Tools for those working heavily with strings
Date: Sun, 24 Jul 2022 15:11:06 +0200 [thread overview]
Message-ID: <8635eqhd05.fsf@gnu.org> (raw)
In-Reply-To: <N7k-xRK--3-2@tutanota.com> (carlmarcos's message of "Sun, 24 Jul 2022 13:42:14 +0200 (CEST)")
carlmarcos--- via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org> writes:
> What can I use to test whether a string in composed of whitespace or
> is empty?
I'm not sure if I understand the "composed of whitespace" part
correctly, but you can try:
(let ((s "With space"))
(and (string-match " " s)
(message "With space")))
(let ((s " "))
(and (string-match "\\`[[:space:]]*\\'" s)
(message "Only spaces")))
(let ((s ""))
(and (string= s "")
(message "Empty string")))
(let ((s ""))
(and (= (length s) 0)
(message "Empty string")))
Best, Arash
next prev parent reply other threads:[~2022-07-24 13:11 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-24 5:04 Tools for those working heavily with strings carlmarcos--- via Users list for the GNU Emacs text editor
2022-07-24 5:11 ` Jean Louis
2022-07-24 5:17 ` carlmarcos--- via Users list for the GNU Emacs text editor
2022-07-24 8:45 ` Jean Louis
2022-07-24 8:44 ` Jean Louis
2022-07-24 11:12 ` carlmarcos--- via Users list for the GNU Emacs text editor
2022-07-24 11:26 ` tomas
2022-07-24 11:42 ` carlmarcos--- via Users list for the GNU Emacs text editor
2022-07-24 13:11 ` Arash Esbati [this message]
2022-07-24 13:17 ` tomas
2022-07-24 13:20 ` Philip Kaludercic
2022-07-24 13:23 ` tomas
2022-07-24 14:45 ` Philip Kaludercic
2022-07-24 20:04 ` Jean Louis
2022-07-24 20:00 ` Jean Louis
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