Unicode Emoji 5.0 characters now final

[Richard Wordingham]

On Thu, 30 Mar 2017 00:52:03 +0200
Charlotte Buff <irgendeinbenutzername at gmail.com> wrote:

> And this is where the problem becomes even worse. Because there are no
> “flag tofus” for 3166-2 regions. Unlike Regional Indicator Sequences,
> the fallback for all unsupported tag sequences looks exactly the same
> and carries absolutely no meaning unless put through some Unicode
> analyzer machine: �� WAVING BLACK FLAG, a well-supported emoji that
> means nothing in the context it is used in, followed by a single,
> featureless tofu. At least a text containing ten different
> unsupported RI sequences will show you ten distinct images, even if
> you are completely unaware that those peculiar pairs of colourful
> letters you’ve just been sent are used to build flag emoji.

I don't see why the tag characters can't be represented by some form of
corresponding ASCII characters as a fallback registering.  The
bracketing pair U+1F3F4 WAVING BLACK FLAG .. U+E007F CANCEL TAG
declares a sequence of 3 to 6 intervening ordinary tags to be a flag
emoji, and in an OpenType font a GSUB contextual substitution can
easily convert unrecognised sequences to modified ASCII characters.  It
does not have to explicitly handle each possible combination.

Richard.