In Kurdish Sorani initial vocals are preceded with a hamza. The current practice is to type a separate hamza and then the vocal. This is suboptimal and causes several problems with collation, spellchecking, searching and the like. However, it is possible to regard the initial hamza not as a “real” separate letter but as a diacritic of the vocal.
There has been a proposal to let the initial hamza be rendered by the fonts rather than typed with the keyboard. There is an (incomplete) implementation of this using OpenType technology in the font XB Shafigh Kurd found on irmug.org:
However, this issue should better be solved by extending the Unicode standard than by creating incompatible fonts. Here is a list of ligatures that are already there and those that are missing. Also you will find absolutely necessary ligatures for “Lam with small v” that are still missing in the Unicode standard.
Ligatures already defined in Unicode 5.1
- U+FBEA ARABIC LIGATURE YEH WITH HAMZA ABOVE WITH ALEF ISOLATED FORM more
- U+FBEE ARABIC LIGATURE YEH WITH HAMZA ABOVE WITH WAW ISOLATED FORM more
- U+FBF2 ARABIC LIGATURE YEH WITH HAMZA ABOVE WITH OE ISOLATED FORM more
- U+FBF9 ARABIC LIGATURE UIGHUR KIRGHIZ YEH WITH HAMZA ABOVE WITH ALEF more
- U+FC04 ARABIC LIGATURE YEH WITH HAMZA ABOVE WITH YEH ISOLATED FORM more
Completely missing ligatures
- ARABIC LIGATURE YEH WITH SMALL V WITH HAMZA ABOVE ISOLATED FORM (derived from U+06CE ARABIC LETTER YEH WITH SMALL V
- ARABIC LIGATURE YEH WITH SMALL V WITH HAMZA ABOVE INITIAL FORM (derived from U+06CE ARABIC LETTER YEH WITH SMALL V
- ARABIC LIGATURE YEH WITH HAMZA ABOVE INITIAL FORM
- ARABIC LIGATURE LAM WITH SMALL V WITH ALEF ISOLATED FORM (derived from U+06B5 ARABIC LETTER LAM WITH SMALL V)
- ARABIC LIGATURE LAM WITH SMALL V WITH ALEF TERMINAL FORM (derived from U+06B5 ARABIC LETTER LAM WITH SMALL V)
(Of course, instead of “Arabic Ligature...” you can could each of them “Kurdish letter...”)
Letters that are superfluous
These letters are said to be Kurdish in the Unicode specification, but aren’t. http://www.unicode.org/charts/PDF/U0600.pdf
