From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Nick Dokos Newsgroups: gmane.emacs.help Subject: Re: Executing part of the code instead of another Date: Wed, 07 Oct 2020 13:29:24 -0400 Message-ID: <87pn5uvtaj.fsf@alphaville.usersys.redhat.com> References: <87imbm3llg.fsf@ebih.ebihd> <87blhe3kxg.fsf@ebih.ebihd> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="23836"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:BxITtitWm22U+vl1l0gjW8GjSyI= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Wed Oct 07 19:34:42 2020 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 1kQDKs-00064t-6t for geh-help-gnu-emacs@m.gmane-mx.org; Wed, 07 Oct 2020 19:34:42 +0200 Original-Received: from localhost ([::1]:59002 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kQDKr-0002ik-5K for geh-help-gnu-emacs@m.gmane-mx.org; Wed, 07 Oct 2020 13:34:41 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:59406) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kQDFt-0006tx-DN for help-gnu-emacs@gnu.org; Wed, 07 Oct 2020 13:29:33 -0400 Original-Received: from static.214.254.202.116.clients.your-server.de ([116.202.254.214]:38074 helo=ciao.gmane.io) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kQDFr-0000CP-Th for help-gnu-emacs@gnu.org; Wed, 07 Oct 2020 13:29:33 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1kQDFo-000Adh-VF for help-gnu-emacs@gnu.org; Wed, 07 Oct 2020 19:29:28 +0200 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/07 13:29:29 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: 5 X-Spam_score: 0.5 X-Spam_bar: / X-Spam_report: (0.5 / 5.0 requ) BAYES_00=-1.9, DKIM_ADSP_CUSTOM_MED=0.001, FORGED_GMAIL_RCVD=1, FREEMAIL_FORGED_FROMDOMAIN=0.248, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.249, NML_ADSP_CUSTOM_MED=0.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 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" Xref: news.gmane.io gmane.emacs.help:124365 Archived-At: Christopher Dimech writes: > I have tried executing the following condition (if (nb > na)) > > (setq na 2) > (setq nb 5) > ( if (> nb na) > (message "nb > na [condition true]") > (message "condition false") > ) > > I highlighted the region then pressed C-x C-e > It returned the first message as expected, but when I tried > the next one, I still got the first message. > `C-x C-e` is bound to `eval-last-sexp` which evaluates the *last* sexp: the if. It does not evaluate the setq's (setting the region does *NOT* matter for it - try `M-x eval-region' for that) > (setq na 2) > (setq nb 1) > ( if (> nb na) > (message "nb > na [condition true]") > (message "condition false") > ) > > > > >> Sent: Wednesday, October 07, 2020 at 9:20 AM >> From: "Robert Pluim" >> To: "Christopher Dimech" >> Cc: moasenwood@zoho.eu, help-gnu-emacs@gnu.org >> Subject: Re: Executing part of the code instead of another >> >> >>>>> On Wed, 7 Oct 2020 09:01:00 +0200, Christopher Dimech said: >> >> Christopher> What can one use if there is an else branch with multiple commands, as I would >> Christopher> like to use it. >> >> From 'C-h f if' >> >> if is a special form in `C source code'. >> >> (if COND THEN ELSE...) >> >> Probably introduced at or before Emacs version 1.1. >> >> If COND yields non-nil, do THEN, else do ELSE... >> Returns the value of THEN or the value of the last of the ELSE's. >> => THEN must be one expression, but ELSE... can be zero or more expressions. >> If COND yields nil, and there are no ELSE's, the value is nil. >> >> >> Robert >> -- >> > > -- Nick "There are only two hard problems in computer science: cache invalidation, naming things, and off-by-one errors." -Martin Fowler