[XeTeX] Numerals in Right-to-Left

[Jonathan Kew]

On 18 Nov 2004, at 4:50 am, Christopher Creutzig wrote:

> Hans Hagen wrote:
>
>> actually this kind of features should be built in, kind of:
>> \xetexdigitbase=<number>
>> \def\arabicnumber  {\xetexdigitbase"0660\relax}
>> \def\persiannumber {\xetexdigitbase"06F0\relax}
>
>  Perhaps \font\arabfont="Geeza Pro:mapping=arabicnumers" and 
> \font\persianfont="Geeza Pro:mapping=persiannumbers"?

That's a great suggestion. It didn't even occur to me, but yes, it 
should work; you'd just need to create a TECkit mapping that converts 
the Latin digits to Arabic or Persian respectively.

>   (Can mappings be nested, to additionally include the tex-text 
> mapping for --- etc.?)

No (though there's nothing to stop you including those mapping rules in 
the same table as the digits).

OTOH, I see little reason to do so; the tex-text mappings are 
specifically for emulating the TeX Roman font encodings with Unicode 
Latin fonts. I don't see much sense in using those input conventions 
within Unicode Arabic text. But there's nothing to stop someone using 
such a mapping if desired.

JK