unofficial mirror of emacs-tangents@gnu.org
 help / color / mirror / Atom feed
From: Alan Mackenzie <acm@muc.de>
To: chad <yandros@gmail.com>
Cc: emacs-tangents@gnu.org
Subject: Re: Display of undisplayable characters: \U01F3A8 instead of diamond
Date: Fri, 2 Sep 2022 21:52:44 +0000	[thread overview]
Message-ID: <YxJ7LFCY26bJ4zWI@ACM> (raw)
In-Reply-To: <CAO2hHWYo=MpA3RzogMC3PTqZ9YKasZM1ptgOVDdc-PRJwDpOAg@mail.gmail.com>

Hello, Chad.

On Fri, Sep 02, 2022 at 16:39:29 -0400, chad wrote:
> On Fri, Sep 2, 2022 at 3:25 PM Emanuel Berg <incal@dataswamp.org> wrote:

> > > I understand (academically) that once someone has adapted
> > > themselves to a particular set of bugs, shortcomings, and
> > > limitations

> > But here the bug was actually better from our perspective ...


> The bug was better in that the undefined behavior from sending known-bad
> data to the console hasn't yet caused you trouble that you've identified.

We weren't talking about bad data.  We were talking about sending valid
UTF-8 sequences to the Linux console.  This console is programmed to
handle these correctly, whether or not there is a matching font entry
for that UTF-8 sequence.

> Everyone (who's looked at the code) acknowledges that it was doing the
> wrong thing.

This is untrue.  I've looked at the code, and consider it was doing the
right thing.  In fact, I've perused the Linux console code too, and
vaguely remember its handling of glyph-less outputs.

> The fact that the bug didn't hurt you and you got used to it is
> exactly what I meant by "adapted themselves".

What bug?  I can't see a bug.  But I've already half-volunteered to work
on it.  Maybe other console types don't handle random UTF-8 byte
sequences well.  I don't know.  But Linux does.

> What the other user (RMS, in this case) _wanted_ to do was to use a console
> (not window system) emacs to look at a range of characters that extends
> beyond ASCII.

Of course.  So do I.  The Linux console is designed and implemented to
support characters beyond ASCII.  It's restriction is to 256 distinct
character glyphs.

> The specific implementations he was using did that right some of the
> time and wrong some of the time.

Too many pronouns.  What are you saying?  To what are you referring by
"specific implementations"?  Implementations of what?  You're saying
these implementations did "that" right some of the time.  What does
"that" refer to?  What do you mean by wrong?  

> When it was wrong, it failed in a certain way. He adapted himself to
> that failure.

I don't see any failure.  Richard's complaint was that characters
without glyphs were getting displayed as long hex strings rather than
the "diamond" that they were previously displayed as.  I think the
complaint has merit.  It seems to me to be a classic case for a user
option.

> The alternative that emacs-devel is trying to establish (via experiments,
> etc/PROBLEMS changes, and perhaps code patches) will make the system fail
> less often -- that is, do what the user wants more often. The argument in
> question is basically "Don't make the software do what the user wants more
> often if it changes away from the bugs that are already familiar to me",
> especially when that argument is expressed *in the middle of fixing the
> problem*, as a discouragement from fixing the problem for all users, then
> we've arrived at "That's horrifying." ala XKCD 1172.

????

> ~Chad

-- 
Alan Mackenzie (Nuremberg, Germany).



  parent reply	other threads:[~2022-09-02 21:52 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <E1oRQ6X-0007In-OK@fencepost.gnu.org>
     [not found] ` <87edx28cl1.fsf@disroot.org>
     [not found]   ` <E1oSVZB-0008Vf-1X@fencepost.gnu.org>
     [not found]     ` <83y1v7w6eu.fsf@gnu.org>
     [not found]       ` <E1oSsba-00065k-NL@fencepost.gnu.org>
     [not found]         ` <dacea928880b805d23c2@heytings.org>
     [not found]           ` <E1oTtfF-0001PX-2x@fencepost.gnu.org>
     [not found]             ` <2f302d1c3966849477b3@heytings.org>
     [not found]               ` <YxHlIPwwApfe5fuk@ACM>
     [not found]                 ` <83mtbiovzr.fsf@gnu.org>
     [not found]                   ` <YxIHp5P8sBRjz/Vg@ACM>
     [not found]                     ` <83a67hq3l7.fsf@gnu.org>
2022-09-02 14:39                       ` Display of undisplayable characters: \U01F3A8 instead of diamond chad
2022-09-02 14:42                         ` Gregory Heytings
2022-09-02 18:49                         ` Emanuel Berg
2022-09-02 19:41                           ` Gregory Heytings
2022-09-02 21:13                             ` Emanuel Berg
2022-09-02 20:39                           ` chad
2022-09-02 21:14                             ` Emanuel Berg
2022-09-02 21:52                             ` Alan Mackenzie [this message]
2022-09-03  0:33                               ` Gregory Heytings
2022-09-03  1:41                                 ` Emanuel Berg

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/emacs/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YxJ7LFCY26bJ4zWI@ACM \
    --to=acm@muc.de \
    --cc=emacs-tangents@gnu.org \
    --cc=yandros@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).