Has anyone looked/used Antlr for Query Parser capabilities? There was
some discussion over at Apache Labs that might bear discussing in
light of our new Query Parser contrib.
Begin forwarded message:
From: Tim Williams <william...@gmail.com>
Date: August 17, 2009 8:09:04 PM EDT
To: l...@labs.apache.org
Subject: Re: Lab - Esqueranto
Reply-To: l...@labs.apache.org
On Mon, Aug 17, 2009 at 7:00 PM, Grant
Ingersoll<gsing...@apache.org> wrote:
On Aug 2, 2009, at 1:43 PM, Tim Williams wrote:
Hi Martin,
Sure, if it works like I envision it, Lucene would just be *one*
concrete tree grammar implementation - there could be others (ie
OracleText), I'm thinking it is broader than one implementation -
otherwise, I reckon it's Yet Another Lucene Query Parser (YALQP).
For more practical reasons, I'm not a Lucene committer and it'd be
slow going to play around with this through JIRA patches to their
sandbox.
FWIW, Lucene has recently added a new, more flexible Query Parser
that
allows for separation of the various pieces (syntax, intermediate
representation, Lucene Query). You might want to check it out and
see how
that fits
Thanks Grant, yeah I've looked at that and it seems really (overly?)
complex for what I'm trying to achieve. It seems to re-implement much
of the goodness that antlr provides for free. For example, with antlr
I already get a lexer/parser grammar separate from the tree grammar.
So, to plug in a new parser syntax is trivial - just implement a new
lexer/parser grammar that provides tree rewrites consistent with a
lucene tree grammar. Conversely, to implement a new concrete
implementation, just implement a new tree grammar for the existing
lexer/parser grammar.
Of course, maybe I'll get down this road and realize how naive my path
is and just switch over. For now, just looking at a query parser
that, by itself, is approaching the size of the lucene core code base
is intimidating:) Thanks for the pointer though, I'm subscribed over
there and keep an eye out for progress on the new parser....
Thanks,
--tim
---------------------------------------------------------------------
To unsubscribe, e-mail: labs-unsubscr...@labs.apache.org
For additional commands, e-mail: labs-h...@labs.apache.org
