[Dev-luatex] Libhyphen

[Stephan Hennig]

schrieb Khaled Hosny:
> On Wed, Sep 21, 2011 at 01:00:08AM +0200, Stephan Hennig wrote:
>> 
>> The same pattern approach can be used to handle non-standard
>> hyphenation, ligaturing, round-s recognition, etc.  (I think there are
>> use-cases in Arabic script as well.)
> 
> I've to admit this is all Greek to me :) (the only language written in
> Arabic script that accepts hyphenation is Uyghur, and that is for the
> new, Chinese-imposed orthography).

I didn't mean hyphenation in Arabic script.  In Latin black letter
script there are two different glyphs for the small letter s -- the long
ſ and the usual round s.  Most keyboards don't provide a key for the ſ,
so source documents usually make use of the round s only.  To put an ſ
at the respective places in the typeset document, the traditional way is
to mark-up those places with s+ or s: (different black letter fonts and
support packages use different conventions).

Now, automatically applying glyph substitution at the correct places
within a character stream /without/ mark-up is pretty much the same
problem as finding hyphenation positions within a character stream
without mark-up.  The same holds for applying non-standard hyphenation
without mark-up or applying ligatures at the correct places only without
mark-up.  Currently, TeX inserts ligatures based on a greedy rule, which
produces many false positives in languages with compound words.

For Arabic script, I referred to glyph substitution.  But I don't know
enough about Arabic script to explain further. :)

Best regards,
Stephan Hennig