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: [External] : Re: Emacs 30.0 warning from `cl-pushnew' and `memql' Date: Sat, 31 Dec 2022 00:03:56 +0100 Message-ID: <87y1qosdcz.fsf@dataswamp.org> References: <878ritgaty.fsf@dataswamp.org> <87o7rprvia.fsf@web.de> <87zgb913fg.fsf@dataswamp.org> <87ilhveo2s.fsf@web.de> <877cyafzit.fsf@dataswamp.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="23028"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:ntvTT4T+8s+cghOd+MkUtsDyOxc= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Sat Dec 31 17:11:30 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 1pBeSH-0005mL-KV for geh-help-gnu-emacs@m.gmane-mx.org; Sat, 31 Dec 2022 17:11:29 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pBeRn-0005l5-0Q; Sat, 31 Dec 2022 11:11:00 -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 1pBOQ4-0007kH-Sg for help-gnu-emacs@gnu.org; Fri, 30 Dec 2022 18:04:09 -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 1pBOQ3-00010j-7D for help-gnu-emacs@gnu.org; Fri, 30 Dec 2022 18:04:08 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1pBOQ1-000ADm-Br for help-gnu-emacs@gnu.org; Sat, 31 Dec 2022 00:04:05 +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: Sat, 31 Dec 2022 11:10:51 -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:142066 Archived-At: Drew Adams wrote: >> Applicative order AKA strict evaluation: a function is >> undefined if any of its arguments are. >> >> So in practice, that means they are computed first. >> >> And that makes sense! Since a function f(x, y) is very much >> a function of x and y ... > > Uh, being a function of x and y doesn't imply that both > x and y always need to be known (calculated). > > `if' is a function of all of its args, but in some cases it > need not evaluate all of them. Not unlike the Stanley Cup Playoffs - they are best-of-7, not first-to-4. Or wait ... should it be the other way around? > Same with `*': if one of the args is zero then no need to > calculate the others. Etc. `or' short-circuiting for that matter. > To make normal order etc. evaluation efficient you need to > make it _fully_ lazy: don't copy or evaluate the same > expression multiple times, but use graph reduction > (sharing) instead. Disintegrate everything to fragments. Filter out duplicates and compute. Put it back together, with copies for the blanks? -- underground experts united https://dataswamp.org/~incal