[Xapian-discuss] xapian + plpgsql crash? have backtrace...

Olly Betts olly at survex.com
Mon Nov 1 18:12:28 GMT 2004


On Mon, Nov 01, 2004 at 01:03:40AM -0800, Eric Parusel wrote:
> It seems to run fine if I use Search::Xapian::Query instead of 
> Search::Xapian::QueryParser...
> 
> Using QueryParser would make it easier to support more complex search 
> queries, but I'm not sure what could be done to get it working properly 
> in my instance...

Someone needs to rework the parser to make it reentrant, and it'll
probably need to be me as I suspect I understand it much better than
anyone else!

I've had a look at the options.  Bison's C++ support is still
experimental (as it has been for several years).  So I think we need to
change parser frameworks.  The options are something yacc-like (e.g.
Lemon uses a similar syntax to yacc/bison, but isn't 100% compatible)
or something more radically different (e.g. spirit which allows you to
write C++ code which closely mirrors BNF grammar rules - by clever use
of operator overloading and templates the code-generation stage is done
by C++).

The first approach may be quicker, but I'm not sure which is better
overall.  If anyone's used Spirit (or something similar) I'd be
interested to hear your experiences.

> I will most likely just settle on the use of ::Query as I am quite short 
> on time :)

You'll probably need to short term - I suspect it'll be a while before
I'll have this sorted out.

Cheers,
    Olly



More information about the Xapian-discuss mailing list