Different Bidirectional Character Types

Eli Zaretskii eliz at gnu.org
Sun Jul 3 04:42:39 CDT 2022

> Date: Sun, 03 Jul 2022 09:20:07 +0000
> From: Andreas Prilop via Unicode <unicode at corp.unicode.org>
> I ask about the differences
>   “555-2368” vs. “2368-555”
>      “1=3−2” vs. “1=2−3”
> “1999-12-31” vs. “31-12-1999”
> The Bidirectional Algorithm is responsible for these differences. But why?

Because that's how the users of each script want the text to be
displayed in these cases.  The UBA was specified as it is to satisfy
the expectations of the users of the respective scripts.  Those
expectations have to do with history, traditions, and culture.

And please note that your cases are no longer just numbers, they
involve the dash ('-'), which is a "weak" character, and its
reordering for display depends on surrounding text.

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