Re: [basex-talk] collection('i_do_not_exist')/users/user[@name=()] is () even if i_do_not_exist does not exit

[Omar Siam]

Well it is definitly an optimization that is new to BaseX 10. But I 
think I found a way to default to "" where I just passed () from a 
variable before.

Am 23.03.2023 um 15:00 schrieb Christian Grün:
Hi again, Omar,
The behavior may be surprising, but it's valid: If it can be detected 
at compile time that an expression will never yield results, it can be 
simplified and rewritten to an empty sequence, no matter if a 
referenced database may possibly exist at runtime.

Hope this helps,
Christian



Omar Siam <omar.s...@oeaw.ac.at> schrieb am Do., 23. März 2023, 14:49:

    Hi,

    Either I found an interesting new XQuery feature or a bug:

    collection('i_do_not_exist')/some/path[@attr=()] retruns the empty
    sequence whereas

    collection('i_do_not_exist')/some/path throws an error
    err:FODC0002 so does
    collection('i_do_not_exist')/ome/path[@attr="i_am_an_attr"]

    Am I missing something?

    Best regards,

    -- 
    Mag. Ing. Omar Siam
    Austrian Center for Digital Humanities and Cultural Heritage
    Österreichische Akademie der Wissenschaften | Austrian Academy of
    Sciences
    Stellvertretende Behindertenvertrauensperson | Deputy
    representative for disabled persons
    Bäckerstraße 13, 1010 Wien, Österreich | Vienna, Austria
    T: +43 1 51581-7295
    omar.s...@oeaw.ac.at | www.oeaw.ac.at/acdh
    <http://www.oeaw.ac.at/acdh>


--
Mag. Ing. Omar Siam
Austrian Center for Digital Humanities and Cultural Heritage
Österreichische Akademie der Wissenschaften | Austrian Academy of Sciences
Stellvertretende Behindertenvertrauensperson | Deputy representative for 
disabled persons
Bäckerstraße 13, 1010 Wien, Österreich | Vienna, Austria
T: +43 1 51581-7295
omar.s...@oeaw.ac.at  |www.oeaw.ac.at/acdh