From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 15353 invoked from network); 1 Aug 2020 00:01:12 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 1 Aug 2020 00:01:12 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id 8059E9CB55; Sat, 1 Aug 2020 10:01:07 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 3E0109C9E3; Sat, 1 Aug 2020 10:00:29 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id DB2899C9E3; Sat, 1 Aug 2020 10:00:24 +1000 (AEST) Received: from mercury.lcs.mit.edu (mercury.lcs.mit.edu [18.26.0.122]) by minnie.tuhs.org (Postfix) with ESMTPS id 42ABA93DFC for ; Sat, 1 Aug 2020 10:00:24 +1000 (AEST) Received: by mercury.lcs.mit.edu (Postfix, from userid 11178) id 3CF0818C0C0; Fri, 31 Jul 2020 20:00:23 -0400 (EDT) To: tuhs@minnie.tuhs.org Message-Id: <20200801000023.3CF0818C0C0@mercury.lcs.mit.edu> Date: Fri, 31 Jul 2020 20:00:23 -0400 (EDT) From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Subject: Re: [TUHS] Regular Expressions 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: , Cc: jnc@mercury.lcs.mit.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > From: Will Senn > I don't really understand how they work. > ... > maybe the way to understand the unix regex lies in a careful > investigation into how it is implemented I'm not sure what I did, but it wasn't the latter, since I have no idea how they are done! I just mentally break the regex search string up into substrings (I use them most in Epsilon, which has syntax to do substrings of search strings, which helps a lot); past that, I think it's just using them and getting used to them. > an IBM 7094 (whatever that is) IBM's last 36-bit scientific mainframe before the System/360's. CTSS (which DMR held out as the ancestor of Unix) ran on 7094's. Noel