From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=0.3 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE,RDNS_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.2 Received: (qmail 20587 invoked from network); 20 Mar 2020 23:15:21 -0000 Received-SPF: pass (minnie.tuhs.org: domain of minnie.tuhs.org designates 45.79.103.53 as permitted sender) receiver=inbox.vuxu.org; client-ip=45.79.103.53 envelope-from= Received: from unknown (HELO minnie.tuhs.org) (45.79.103.53) by inbox.vuxu.org with ESMTP; 20 Mar 2020 23:15:21 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id EE5B89D551; Sat, 21 Mar 2020 09:15:17 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 0E5239CDA9; Sat, 21 Mar 2020 09:15:05 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id F3F519CDA9; Sat, 21 Mar 2020 09:15:02 +1000 (AEST) Received: from mail.cs.dartmouth.edu (mail.cs.dartmouth.edu [129.170.212.100]) by minnie.tuhs.org (Postfix) with ESMTPS id 6F9E49CD87 for ; Sat, 21 Mar 2020 09:15:02 +1000 (AEST) Received: from coolidge.cs.dartmouth.edu (coolidge.cs.dartmouth.edu [129.170.213.217]) by mail.cs.dartmouth.edu (8.15.2/8.15.2) with ESMTPS id 02KNF0wq1829646 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO) for ; Fri, 20 Mar 2020 19:15:00 -0400 Received: from coolidge.cs.dartmouth.edu (localhost [127.0.0.1]) by coolidge.cs.dartmouth.edu (8.15.2/8.15.2) with ESMTP id 02KNF0Wj305877 for ; Fri, 20 Mar 2020 19:15:00 -0400 Received: (from doug@localhost) by coolidge.cs.dartmouth.edu (8.15.2/8.15.2/Submit) id 02KNF088305876 for tuhs@tuhs.org; Fri, 20 Mar 2020 19:15:00 -0400 From: Doug McIlroy Message-Id: <202003202315.02KNF088305876@coolidge.cs.dartmouth.edu> Date: Fri, 20 Mar 2020 19:15:00 -0400 To: tuhs@tuhs.org User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: Re: [TUHS] RPN (was The most surprising Unix programs) X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Sorry to flog this topic, but the two examples below are an unfair comparison. What happened to the multiplications in the second? And two of the [enter]s in the first are unnecessary. Ironically three of the four operations in the second are actually reverse Polish! If you had to utter sqrt first, as we do on paper and in speech, things wouldn't look so great. [a] [enter] [a] [enter] [multiply] [b] [enter] [b] [enter] [multiply] [add] [square root] [a] [square] [plus] [b] [square] [square root] Doug