From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Why is FUNC in cl-callf not allowed to be an expression? Date: Thu, 09 May 2019 20:47:48 -0400 Message-ID: References: <874l631ek1.fsf@web.de> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="203130"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri May 10 02:48:10 2019 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hOthq-000qcr-21 for ged-emacs-devel@m.gmane.org; Fri, 10 May 2019 02:48:10 +0200 Original-Received: from localhost ([127.0.0.1]:34707 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hOtho-00058x-Sz for ged-emacs-devel@m.gmane.org; Thu, 09 May 2019 20:48:08 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:53317) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hOthi-00058h-OU for emacs-devel@gnu.org; Thu, 09 May 2019 20:48:03 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hOthh-0008AI-QH for emacs-devel@gnu.org; Thu, 09 May 2019 20:48:02 -0400 Original-Received: from [195.159.176.226] (port=35176 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hOthh-00089H-Jb for emacs-devel@gnu.org; Thu, 09 May 2019 20:48:01 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.89) (envelope-from ) id 1hOthg-000qS8-0i for emacs-devel@gnu.org; Fri, 10 May 2019 02:48:00 +0200 X-Injected-Via-Gmane: http://gmane.org/ Cancel-Lock: sha1:nq44ROzfLCMtpQcOZd/oQDMJI/I= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 195.159.176.226 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:236349 Archived-At: > I wonder why the FUNC argument in cl-callf is restricted to symbols (and > lambda expressions, though this is not documented). I don't see any > reason to disallow arbitrary expressions, besides, maybe, that symbols > would become ambiguous. `callf` has been in cl.el "for ever" but it's not in Common-Lisp, so I don't really know where it comes from. I agree that when I moved it to cl-lib, I missed an opportunity to fix it and make it take a normal expression as first argument. > I really would like to have an gv-callf that would simply interpret the > function argument as an expression. cl-callf just saves the programmer > from typing the #' but forbids many use cases. FWIW, you can circumvent this with (cl-flet ((f )) (cl-callf f ...)) > I think I would even like it most like this: > > (defmacro gv-callf (call &optional n) > (gv-letplace (_getter setter) (nth (or n 1) call) > (funcall setter call))) It's cute, tho I'm not too fond of specifying the place via a number, personally, Stefan