On Tue, Aug 12, 2025 at 9:09 AM Chao Li <li.evan.c...@gmail.com> wrote:
[bringing this back to the original thread] > So, I compared 2000 ucm with 2005 ucm also compared 2005 ucm with 2022 ucm. > Then I found that some changed in 2005 is reverted in 2022, that why diff > between 2000 and 2022 is small. For example, the following mappings Yes, this was mentioned in the "disruptive changes" document linked in my first email in this thread: "The 2005 edition included 6 characters with double mappings. The 2022 edition removes the double mappings. The 2005 edition included 9 characters from the CJK Compatibility Ideographs block. In Unicode/10646, these all have canonical decomposition mappings to characters in the URO. In the 2022 edition, these nine compatibility characters are removed." > So, for how to create patch 2, I think we have 3 options: > > 1. As planned, update to the latest version of 2000 ucm, then skip 2005 and > directly upgrade to 2022 in patch 3. This way, we just honor 2000 ucm > regardless that the change is actually introduced by 2005. > > 2. Skip the latest version of 2000 ucm and upgrade to 2005 ucm. This way will > clearly show the upgrade path 2000->2005->2022. Downside is that 2005 > introduced some changes that are reverted in 2022, which will cause some > unnecessary changes in map files. > > 3. Skip patch 2, directly go to patch 3. So that, patch 3 will include > changes introduced by both 2005 and 2022. This way makes minimum changes to > map files. #3 is what I had in mind to begin with unless we found some reason not to. Minimizing churn is a lucky side effect that reinforces that choice. Before getting to that, I thought I'd bring this up to the community: +# Copyright (C) 2000-2009, International Business Machines Corporation and others. +# All Rights Reserved. The previous XML file didn't contain a copyright notice -- does anyone want to make a case for not checking unicode-org's source file into our tree because of this? The 2022 update changes it to # Copyright (C) 2016 and later: Unicode, Inc. and others. # License & terms of use: http://www.unicode.org/copyright.html # Copyright (C) 2000-2012, International Business Machines Corporation and others. # All Rights Reserved. ...and the above links to https://www.unicode.org/license.txt -- John Naylor Amazon Web Services
