[Xapian-discuss] writing match deciders / custom handling of terms

[djcb]

Hi all,

I'm using Xapian for my mail indexer/searcher[1]; the current version
uses Xapian in tandem with SQLite, but I'm making it Xapian-only now,
mainly for reasons of simplification of the code.

Anyhow, I'd have to compliment the Xapian developers for producing such
a nice piece of work! It works really well, and really fast.[2]

Now, my question is about the MatchDeciders (I think). Suppose I have a
query to find some messages in my Xapian DB, e.g:

     subject:foo AND flags:A

which would match message with subject 'foo' and messages with flag 'A'
(having attachments). In the database, flags are just a number. So, I
need some custom handling of this 'flags:A' term, and match the
appropriate documents.

Now, it seems(?) that MatchDeciders are the way to go -- but I don't see
a way to do the custom handling of the flags parameter -- am I missing
something simple?

Thanks in advance!
Dirk.

Footnotes: 
[1]  http://www.djcbsoftware.nl/code/mu

[2] But: there are some things that seem a bit strange though; e.g. there seems
 to be no API to add the prefix to add_term, requiring me to manually
 prefix the strings, which seems a bit hackish... and the Xapian::Sorter
 which returns a string, which is then sorted; I was expecting something
 similar to std::less, or GCompareFunc in GLib; not being able to do
 the comparison myself forces me to pad numeric values with 0 etc., so
 the sorting works 

-- 
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Dirk-Jan C. Binnema <djcb at djcbsoftware.nl>
blog: http://www.djcbsoftware.nl/ChangeLog (NL)
      http://djcbflux.blogspot.com (EN)
chat: djcb at jabber.org
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