From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Filipe Silva Newsgroups: gmane.emacs.help Subject: grokking cl-callf Date: Mon, 10 Jul 2017 15:46:02 -0300 Message-ID: NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1499712455 4586 195.159.176.226 (10 Jul 2017 18:47:35 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 10 Jul 2017 18:47:35 +0000 (UTC) To: Help Gnu Emacs mailing list Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Jul 10 20:47:31 2017 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dUdiS-0000ob-Qd for geh-help-gnu-emacs@m.gmane.org; Mon, 10 Jul 2017 20:47:28 +0200 Original-Received: from localhost ([::1]:42514 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dUdiY-0007wU-6m for geh-help-gnu-emacs@m.gmane.org; Mon, 10 Jul 2017 14:47:34 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:34475) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dUdi8-0007wO-2c for help-gnu-emacs@gnu.org; Mon, 10 Jul 2017 14:47:08 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dUdi5-0002Sg-1J for help-gnu-emacs@gnu.org; Mon, 10 Jul 2017 14:47:08 -0400 Original-Received: from mail-oi0-f49.google.com ([209.85.218.49]:33241) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1dUdi4-0002Sa-Ro for help-gnu-emacs@gnu.org; Mon, 10 Jul 2017 14:47:04 -0400 Original-Received: by mail-oi0-f49.google.com with SMTP id p188so82564016oia.0 for ; Mon, 10 Jul 2017 11:47:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=Onlw5DdhHQkGwcdNT0e090xhCvedG1DMiKBivyMzZss=; b=UNVAGjOxNTTlfETMHpamlT6/FnLouS0+trFlHXqrKTQLjOd/cQlEmLKBiPC8WOySFT hQ5J1cTGOqtSifFAMaoarhcGVSAsDht6OXlYWdQRL869gbogiAP0QpA/p7TIcio0oQzu tMCQa9Vt1vWqk5UOrIwgF1DsEL3SYt91v+zHBHx9i7OMnwAJGoZROVOySqO8OlM+MOfh fPLDtUe11N/pM9cUNe4Iocz233cpXAfdClrGBQQypo6gJITskIDjurLaivzGA/u0zxLK Nf+SpS3T5vQ2I1BG0FpWPBUvNaGXg94Ir7VEtoQVEtnrPKmfdJEmUMgC+YuYp36akeJv W6eA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=Onlw5DdhHQkGwcdNT0e090xhCvedG1DMiKBivyMzZss=; b=qfocm4wPFg26nfUzhdgTpnz6Ba9kaiVlhA7hcQ25vZhoTuK4YW/ZhmfMBHJyqogt2H MsBECNG8qJimZGWoUAqQX43NIgt1ecXqhwo9oB6dNkaAYTRJtYv7XinLtNb8gawt1O4c J3VDbb0HCKKznF6sT9YWOmmUmXw+QKCls6O6nzJntuGBGZPq4AOZ9weiHTBYtxLZoVzV a1ZoqQ36aADO49LJGmFhipzOoa06UpnlgOXuoj7BCOlZdlMZlKrVMly61irEM8j8s4rs NaY/yuWJ6eUByZqXjiF3vwuiCy2YoCCecFdARB5GrN5QW7/oWJjRwDeEVNCXXm0wbhqE DlvA== X-Gm-Message-State: AIVw1136JHegng9f/kA25aW0X+NsDicnDsoRzDUwg8Yo0MxLEKs2KPlg baTmQa2Na8dy0/cWp/B/E6ESFE4fEw== X-Received: by 10.202.81.146 with SMTP id f140mr10217779oib.125.1499712363375; Mon, 10 Jul 2017 11:46:03 -0700 (PDT) Original-Received: by 10.182.85.69 with HTTP; Mon, 10 Jul 2017 11:46:02 -0700 (PDT) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.85.218.49 X-Content-Filtered-By: Mailman/MimeDel 2.1.21 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.org gmane.emacs.help:113748 Archived-At: 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.