Re: Displaying bytes

[Stefan Monnier <monnier@iro.umontreal.ca>]

>     I don't know you see this "tis620" stuff.
> How strange this discrepancy.  I have a few changes that are not
> installed, but not in anything relevant here.  I last updated
> source code on Nov 18.

Oh wait, I now see: you get `tis620' for chars between 128 ans 160
(i.e. eight-bit-control), and `eight-bit' for chars between 160 and 256.

> Here's what apparently defines that character set, in mule-conf.el:

> (define-charset 'tis620-2533
>   "TIS620.2533"
>   :short-name "TIS620.2533"
>   :ascii-compatible-p t
>   :code-space [0 255]
>   :superset '(ascii eight-bit-control (thai-tis620 . 128)))

Looks like the eight-bit-control here is part of the problem.

> Anyway, please don't overlook the other suggestions in my message
> for how to make things clearer.

Of course.

>> What are the situations where a user is likely to see these stray
>> bytes.
>     There pretty much shouldn't be any in multibyte buffers.
> Would it be good to ask people to send bug reports when these
> stray byte characters appear in multibyte buffers?

No, these chars can appear in cases where Emacs does the right thing.
I.e. sometimes they reflect bugs, but often they just reflect "pilot
errors" or corrupted data completely outside the control of Emacs.


        Stefan