2008/5/28 David Carlisle <davidc@xxxxxxxxx>:
>  title[lang($preferredLanguage)] |
> title[lang($2ndPreferredLanguage)][not(../title[lang($preferredLanguage)])]
>
> which will select  title[lang($preferredLanguage)] if it exists and
> title[lang($2ndPreferredLanguage)] if title[lang($preferredLanguage)]
> does not exist

or in 2.0:

(title[lang($preferredLanguage)], title[lang($2ndPreferredLanguage)])[1]

I guess in 1.0 you might be able to do a union:

(title[....] | title[2nd..)])[1]

..but if they both existed and the 2nd pref occurred first in document
order you would get that instead.

-- 
Andrew Welch
http://andrewjwelch.com
Kernow: http://kernowforsaxon.sf.net/