On Thu, 30 Mar 2017 00:52:03 +0200 Charlotte Buff <[email protected]> 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.
