Re: Can watermarking Unicode text using invisible differences sneak through Emacs, or can Emacs detect it?

[Eli Zaretskii]

> From: Richard Stallman <rms@gnu.org>
> Cc: psainty@orcon.net.nz, luangruo@yahoo.com,
>       kevin.legouguec@gmail.com, emacs-devel@gnu.org
> Date: Tue, 08 Feb 2022 23:06:26 -0500
> 
> However, some of those COMBINING forms have no non-COMBINING counterpart.
> For instance, there is COMBINING ZIGZAG ABOVE, but no ZIGZAG ABOVE.
> 
> How do you represent an uncombined zigzag-above in Unicode?
> Put it after SPACE as a combination?

If I understand correctly what you want, you should use U+25CC DOTTED
CIRCLE before the combining character, not SPACE.

>   > My point is that there isn't a mechanical way of producing "o/" from
>   > ø, because Unicode decompositions don't support that.
> 
> It wouldn't be very hard to add a list of extra decompositions that
> are not known to Unicode itself.

Sure, but that means we'd need some manually-maintained database
anyway.