Proposal for BiDi in terminal emulators

Egmont Koblinger via Unicode unicode at
Wed Jan 30 09:24:15 CST 2019

> A formatted table is pretty unsuitable for automated processing, and
> obviously meant for human display.

Could you please clarify how exactly that data looks like? Maybe a
tiny hexdump of an example?

Is the RTL piece of text already stored in visual order, that is,
beginning with the leftmost (last logical) letter of the word? If so
then you can sure display it properly in BiDi-unaware rendering
engines (including most terminal emulators currently, as well as in
"explicit" mode according to my specification). That is, whoever
produces that data reverses that word for you?

Or is the RTL piece of text still in its logical order? Then in what
piece of software does this formatted data show up to you in a
readable way?

> You're a terminal emulator maintainer, thus it's natural for you to think
> it's the right place to come up with a solution.

No. I've been a maintainer/developer/contributor to all kinds of
software, including (but not limited to) terminal emulators, apps
running inside terminal emulators, or a pretty complex RTL homepage.
I'm doing my best in looking at the entire ecosystem, and coming up
with a good BiDi-aware interface between terminal emulators and

> I'd argue that it's not --
> all a terminal emulator can do is to display already formatted text, there's
> no sane way to move things around.

You missed that your use case with this table is not the only possible
use case. There are others where the terminal needs to do BiDi. My
work aims to address multiple use cases at once, yours being one of


More information about the Unicode mailing list