Re: Arabic ligatures

Shawn Landden <shawnlandden at tuta dot io> wrote:

> Arabic ligitures have been deprecated[1], despite a need for both
> ligitures and non-ligature versions of the same glyphs.

The only Arabic character that is deprecated in the standard is U+0673
ARABIC LETTER ALEF WITH WAVY HAMZA BELOW. The Wikipedia article cited as
"[1]" does not claim otherwise.

> Amiri uses contextual alternatives for الله. These ligatures are
> used in religious documents[2] via pictures, which seems to be what
> the current Unicode standard recommends.

What is your source for this?

> Unlike the presentation forms, there is case for these phrases and
> formulas to be available both in ligature and non-ligature form.

All Arabic letters and combinations can be rendered in ligated or
non-ligated forms as needed using some combination of ZWJ and ZWNJ. See
TUS 8.0, Section 9.2.

> These ligatures should be non-deprecated and subject to canonical
> decomposition, rather than compatibility decomposition.

Section 9.2 (page 386 ff.) explains the Arabic Presentation Forms-A
block (U+FB50—U+FDFF) in greater detail.

--
Doug Ewell | http://ewellic.org | Thornton, CO 🇺🇸