From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: Re: Closures - do you understand them well? Date: Fri, 09 Dec 2022 06:37:01 +0100 Message-ID: <87r0x9cf42.fsf@dataswamp.org> References: <87lenh7vrn.fsf@web.de> <87tu25d77o.fsf@gnu.org> <87h6y5pt8k.fsf@web.de> <87bkodpqnk.fsf@web.de> <87y1rhckdm.fsf@dataswamp.org> <87a63xns30.fsf@web.de> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="15131"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:azkDSvHK5FeJJMhX7lAxaADQH3w= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Dec 09 11:32:22 2022 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p3ag2-0003eC-Fv for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 09 Dec 2022 11:32:22 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p3afa-0004AY-Il; Fri, 09 Dec 2022 05:31:54 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p3W4l-00070K-2J for help-gnu-emacs@gnu.org; Fri, 09 Dec 2022 00:37:39 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p3W4N-000500-D3 for help-gnu-emacs@gnu.org; Fri, 09 Dec 2022 00:37:30 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1p3W4K-000ADp-Mq for help-gnu-emacs@gnu.org; Fri, 09 Dec 2022 06:37:08 +0100 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: help-gnu-emacs@gnu.org Mail-Copies-To: never Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Fri, 09 Dec 2022 05:31:45 -0500 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 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-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:141502 Archived-At: tomas wrote: >>> OK, so is it the closures? Or the loops? >>> >>> Or ... the lamdas? >>> >>> (setq x 111) >>> >>> (setq f (lambda () x)) >>> >>> (funcall f) >>> >>> (setq x 222) >>> >>> (funcall f) >> >> Maybe I'm too tired, but I don't understand the question. >> What's "it" in the first question? > > My gut reaction was such that the answer to Emanuel's > question would have been "it's the bindings". This is why you should never quote lambdas because if you do, you get the intuitive result: (let ((i 0) (funs '())) (while (< (setq i (1+ i)) 4) (push `(lambda () ,i) funs)) (apply #'+ (mapcar #'funcall funs))) ; 6 -- underground experts united https://dataswamp.org/~incal