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From: Filipe Silva <filipe.silva@gmail.com>
To: Help Gnu Emacs mailing list <help-gnu-emacs@gnu.org>
Subject: grokking cl-callf
Date: Mon, 10 Jul 2017 15:46:02 -0300	[thread overview]
Message-ID: <CAEwkUWPhoEgopfE4AVdpd8U7aUxnTVz_+n3othXcFoKxb2RRtQ@mail.gmail.com> (raw)

A few days ago Stefan Monier gave me an awesome tip about cl-callf:

this snippet:

(if display-line-numbers-current-absolute
(setq display-line-numbers-current-absolute nil)
(setq display-line-numbers-current-absolute t)))

is equivalent to this line:

(cl-callf not display-line-numbers-current-absolute)

So In the same spirit, I'm trying to write a function that toggles showing
line numbers:

to display line numbers:

(setq display-line-numbers 'visual)

to hide line numbers:

(setq display-line-numbers nil)

can I use cl-callf in this case to avoid writing the obvious if bounded
function?

thanks in advance.


             reply	other threads:[~2017-07-10 18:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-07-10 18:46 Filipe Silva [this message]
2017-07-10 21:00 ` grokking cl-callf Stefan Monnier

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