From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Noam Postavsky Newsgroups: gmane.emacs.devel Subject: Re: Scan of regexps in Emacs (March 17) Date: Tue, 2 Apr 2019 10:26:40 -0400 Message-ID: References: <5363970c-3207-1bb4-8b30-74a7d12277cc@cs.ucla.edu> <05269D79-B016-4FCB-94B8-068BF7D1C2D2@acm.org> <3974269b-6cad-0744-bd1f-66c067f94192@cs.ucla.edu> <4b1164c4-e302-ce41-07c3-145d31a97b4c@cs.ucla.edu> <21CCFA3D-B391-44E1-9ED5-1D37009F1988@acm.org> <09AE372B-3A30-4596-8C4E-B9F4CBF6E348@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="136839"; mail-complaints-to="usenet@blaine.gmane.org" Cc: Paul Eggert , Stefan Monnier , Emacs developers To: =?UTF-8?Q?Mattias_Engdeg=C3=A5rd?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Apr 02 16:27:38 2019 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hBKO1-000ZRt-UZ for ged-emacs-devel@m.gmane.org; Tue, 02 Apr 2019 16:27:38 +0200 Original-Received: from localhost ([127.0.0.1]:45970 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hBKO0-0002ft-Ta for ged-emacs-devel@m.gmane.org; Tue, 02 Apr 2019 10:27:36 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:59940) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hBKNL-0002fR-OA for emacs-devel@gnu.org; Tue, 02 Apr 2019 10:26:56 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hBKNJ-0007eY-Tt for emacs-devel@gnu.org; Tue, 02 Apr 2019 10:26:55 -0400 Original-Received: from mail-oi1-x229.google.com ([2607:f8b0:4864:20::229]:36043) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hBKNI-0007dw-Me for emacs-devel@gnu.org; Tue, 02 Apr 2019 10:26:53 -0400 Original-Received: by mail-oi1-x229.google.com with SMTP id l203so9970476oia.3 for ; Tue, 02 Apr 2019 07:26:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=BVZbuwagSeSaFgnUd7xbE8v9J8m15SlD3iA/N6RKevI=; b=GKET/lsKQjkKkbmiU7ZSanf7FG7jZtO6/JhDCSPgJQs3IIvTYe8h1xC/XxDZN8oUqZ Lwl5Eeqt4tKXSi3EgtAHZqqvEkBpR6/3cnP3A2Wu9M2yjYvRaYcPMZtN5caZcFz91CrC ed605xcHRxqkHEYdJiMMjq77fxwAWqVinGrKDOxfzVIJeCb6QeMJ6NuCQneBunl2l6c3 +6NO2XfVHiqmIUzKzZJnztI26dSDWkptwHLJGi+G2g6D3CD2frpj+XEGQddzRSO8tcFU VccoYh+P7Eba5AoOco07OTm4HceZ+s0q56LszjVM9qdZtJVF4nVnyMZZGma4mtU4Y+U2 KYuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=BVZbuwagSeSaFgnUd7xbE8v9J8m15SlD3iA/N6RKevI=; b=tOq1zD0VMooG2okSGL7u2xkrPRpRxeM6y2xGnzKCpkSEDN1FZh1njVTS1jJOekIqk/ xp5fBFqnBlfoHqdepEKH6a5Q7PvnSEPEEdOJDMK9PcQ4NS+gYlrh/LVmH0HvO7kXldp0 oW9cQlEUo5rLRqHBcxTiWsT9s8ndGrmj+VujLj/zH+SXsLLcZJotpDucpHHDGAKNfl08 g4wLZv6bfH+82IewiwBniFk3wJDf1Hm1C7fagMw5YClRXMEb9FWbrcerQSuvfZd/EM4+ tWeY762G4POvwDAZQkm3qpxc+UFwgo4iZKwgdE/TUzKoyp0rDOkANJm4ll/9+3NPsxap 1AFw== X-Gm-Message-State: APjAAAUFA9SzbBUse9PAIq/JbKoL9FgL84WpJXOjpBIcNbrs8exy/fn6 nFBGDiBfx+e1SfEPKhlW8oIL58RFHRbqlzbjzTU= X-Google-Smtp-Source: APXvYqzxkpHG3kOHmbkV8YHCXlM3bm5fW7qbKAGlVCvfPLZIzxg6QqWvuTjG3czqCGFfmsOl2k5UAV1rPgoOG96tDQU= X-Received: by 2002:aca:bf08:: with SMTP id p8mr1872410oif.173.1554215211329; Tue, 02 Apr 2019 07:26:51 -0700 (PDT) In-Reply-To: <09AE372B-3A30-4596-8C4E-B9F4CBF6E348@acm.org> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::229 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:234868 Archived-At: On Tue, 2 Apr 2019 at 10:15, Mattias Engdeg=C3=A5rd wrot= e: > > After looking into it I realized that I don't really know the semantics= here (the text I recently added there seems to be wrong, in some cases), a= nd I have my doubts that anyone else knows the semantics either. The attach= ed patch simply gets rid of that section, leaving the area undocumented. Us= er beware! > > Apparently I don't really know it either -- I just discovered that: > > (string-match "\xff" "\xff") =3D> 0 > (string-match "[\xff]" "\xff") =3D> 0 > (string-match "\xff=C3=A9?" "\xff") =3D> nil > (string-match "[\xff]=C3=A9?" "\xff") =3D> 0 > (string-match "\xff" "\xff=C3=A9") =3D> 0 > (string-match "[\xff]" "\xff=C3=A9") =3D> nil > (string-match "\xff=C3=A9?" "\xff=C3=A9") =3D> 0 > (string-match "[\xff]=C3=A9?" "\xff=C3=A9") =3D> nil See also Bug#3687. https://debbugs.gnu.org/cgi/bugreport.cgi?bug=3D3687