From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: Referring to revisions in the git future. Date: Sat, 01 Nov 2014 08:49:34 +0100 Message-ID: <87k33f4ay9.fsf@fencepost.gnu.org> References: <20141028223312.GB6630@acm.acm> <20141029004942.GA25241@thyrsus.com> <20141029105202.249acb5a@anarchist.wooz.org> <87bnouapiy.fsf@fencepost.gnu.org> <20141029150600.GA5701@thyrsus.com> <20141029141216.7abbbc0d@anarchist.wooz.org> <87tx2m2pw8.fsf@uwakimon.sk.tsukuba.ac.jp> <87sii43u15.fsf@fencepost.gnu.org> <877fzf3dr2.fsf@uwakimon.sk.tsukuba.ac.jp> <87oasrl7sn.fsf@thinkpad-t440p.tsdh.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1414828189 21591 80.91.229.3 (1 Nov 2014 07:49:49 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 1 Nov 2014 07:49:49 +0000 (UTC) Cc: emacs-devel@gnu.org To: "Stephen J. Turnbull" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Nov 01 08:49:44 2014 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XkTRO-0005q2-C6 for ged-emacs-devel@m.gmane.org; Sat, 01 Nov 2014 08:49:42 +0100 Original-Received: from localhost ([::1]:45607 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkTRN-00063c-Pc for ged-emacs-devel@m.gmane.org; Sat, 01 Nov 2014 03:49:42 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36497) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkTRJ-0005yp-2f for emacs-devel@gnu.org; Sat, 01 Nov 2014 03:49:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XkTRI-0003kf-1A for emacs-devel@gnu.org; Sat, 01 Nov 2014 03:49:37 -0400 Original-Received: from fencepost.gnu.org ([2001:4830:134:3::e]:46924) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkTRH-0003kZ-To for emacs-devel@gnu.org; Sat, 01 Nov 2014 03:49:35 -0400 Original-Received: from localhost ([127.0.0.1]:54100 helo=lola) by fencepost.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkTRH-0002qK-9S; Sat, 01 Nov 2014 03:49:35 -0400 Original-Received: by lola (Postfix, from userid 1000) id C20F8DF3E5; Sat, 1 Nov 2014 08:49:34 +0100 (CET) In-Reply-To: <87oasrl7sn.fsf@thinkpad-t440p.tsdh.org> (Tassilo Horn's message of "Sat, 01 Nov 2014 08:05:44 +0100") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2001:4830:134:3::e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:176192 Archived-At: Tassilo Horn writes: > "Stephen J. Turnbull" writes: > >> > 40 hexadecimal digits are pretty unambiguous on their own. >> >> Sure, but I had in mind abbreviations as well. > > According to the Regex Dictionary at http://www.visca.com/regexdict/ > there is no single English word matching the regex "^[a-f0-9]{7,}$" and > AFAICS an abberviated Git SHA is 7 chars wide. It is at least 6 characters I think, more if 6 would not be unambiguous. The problem is that "unambiguous" changes over time and repositories. A historically unambiguous SHA might become ambiguous over time and/or it might be unambiguous in one person's repository but not another. And when garbage collection removes rebased or deleted branches, "unambiguous" might even become shorter again. It's not like anybody's going to want to type off "abbreviations" by hand anyway: too error-prone. Just paste the full thing. Really. I've been developing for years with Git, and that's just what everybody does most of the time. -- David Kastrup