Documentation is not detailed enough.
Analyzers analyze their input (at indexing and searching time).
They are just Java classes that do not know about QueryParser.jj, which
is the only place where '\' is defined as an escape characters (plus
the .java files generated by running QueryParser.jj through JavaCC).
Hence, I believe that if your Analyzer is not explicitly instructed to
leave '\' alone you will think that escaping doesn't work.
Whitespace analyzer I believe works because it doesn't throw out
characters like '\', as I think it only splits token on spaces.
HTH.
Otis
--- Terry Steichen <[EMAIL PROTECTED]> wrote:
> Dave,
>
> I would say you seem to be right. But this is getting very
> frustrating.
> Here is what the Lucene docs say:
>
> <docs quote>
> Lucene supports escaping special characters that are part of the
> query
> syntax. The current list special characters are
>
> + - && || ! ( ) { } [ ] ^ " ~ * ? : \
>
> To escape these character use the \ before the character. For example
> to
> search for (1+1):2 use the query:
>
> \(1\+1\)\:2
>
> </docs quote>
>
> Is the Lucene documentation in error? Does it work but only using
> something
> other than the standard configuration? If so, precisely what
> non-standard
> configuration is necessary?
>
> Why can't these questions be answered simply and clearly?
>
> Terry
>
>
> ----- Original Message -----
> From: "Spencer, Dave" <[EMAIL PROTECTED]>
> To: "Lucene Users List" <[EMAIL PROTECTED]>
> Sent: Tuesday, November 26, 2002 5:02 PM
> Subject: RE: Does Escaping Really Work?
>
>
> My understanding is that "escaping may not work (as Terry and I
> believe)
> however
> a workaround for most 'reasonable' cases is to use
> WhitespaceAnalyzer
> when
> parsing a query".
>
>
> -----Original Message-----
> From: Terry Steichen [mailto:[EMAIL PROTECTED]]
> Sent: Tuesday, November 26, 2002 1:48 PM
> To: Lucene Users List
> Subject: Re: Does Escaping Really Work?
>
>
> Well, pardon me for breathing, Otis.
>
> I didn't make the connection (partly 'cause you changed the subject
> line).
> But anyway, I don't understand your rather oblique answer - does
> escaping
> work or not? Are you saying that, in order for it to work (the way
> the
> docs
> say it does), I need to insert this module in the chain? Or what?
>
> Terry
>
> ----- Original Message -----
> From: "Otis Gospodnetic" <[EMAIL PROTECTED]>
> To: "Lucene Users List" <[EMAIL PROTECTED]>
> Sent: Tuesday, November 26, 2002 3:07 PM
> Subject: Re: Does Escaping Really Work?
>
>
> > Didn't I just answer this last night?
> > WhitespaceAnalyzer?
> >
> > Otis
> >
> > --- Terry Steichen <[EMAIL PROTECTED]> wrote:
> > > I'm confused about how to use escape characters in Lucene. My
> Lucene
> > > configuration is 1.3-dev1 and I use the StandardAnalyzer and
> > > QueryParser.
> > >
> > > My documents have a field called 'path' with a value like
> > > "1102/a55407-2002nov2.xml". This field is indexed but not
> tokenized.
> > > Here are the various queries I've tried and their results:
> > >
> > > 1) When a dash is included in the query, Lucene interprets this
> as a
> > > space. ("path:1102/a55402-2002nov2.xml" is interpreted as
> > > "path:1102/a55402 -body:2002nov2.xml")
> > >
> > > 2) When a backslash is inserted before the dash (and the query
> does
> > > *not* contain a wildcard), Lucene interprets this by inserting a
> > > space in lieu of the next character.
> > > ('path:1102/a55402\-2002nov2.xml' interpreted as
> 'path:"1102/a55402
> > > 2002nov2.xml" [note the space where the dash was]')
> > >
> > > 3) When a backslash is inserted before the dash (and the query
> *does*
> > > contain a wildcard), Lucene interprets this literally, without
> any
> > > conversion. ("path:1102/55407\-2002nov*" is interpreted
> literally).
> > >
> > > 4) When a backslash is inserted before the dash and immediately
> > > followed by a wildcard, Lucene reports an error.
> > > ('path:1102/a55407-*' causes lexical error: Encountered <EOF>
> > > after :"")
> > >
> > > My overall observation is that it appears it is not possible to
> > > escape a dash - is this true?
> > >
> > > A previous post (yesterday) suggests that it is also not possible
> to
> > > escape a backslash. If that's also true, what characters can be
> > > escaped?
> > >
> > >
> > > Regards,
> > >
> > > Terry
> > >
> > >
> > >
> > >
> >
> >
> > __________________________________________________
> > Do you Yahoo!?
> > Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
> > http://mailplus.yahoo.com
> >
> > --
> > To unsubscribe, e-mail:
> <mailto:[EMAIL PROTECTED]>
> > For additional commands, e-mail:
> <mailto:[EMAIL PROTECTED]>
> >
> >
>
>
> --
> To unsubscribe, e-mail:
> <mailto:[EMAIL PROTECTED]>
> For additional commands, e-mail:
> <mailto:[EMAIL PROTECTED]>
>
>
>
> --
> To unsubscribe, e-mail:
> <mailto:[EMAIL PROTECTED]>
> For additional commands, e-mail:
> <mailto:[EMAIL PROTECTED]>
>
>
>
>
> --
> To unsubscribe, e-mail:
> <mailto:[EMAIL PROTECTED]>
> For additional commands, e-mail:
> <mailto:[EMAIL PROTECTED]>
>
__________________________________________________
Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.
http://mailplus.yahoo.com
--
To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]>
For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
