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On Fri, Sep 3, 2010 at 8:51 AM, Mike Taylor <[log in to unmask]> wrote: > On 3 September 2010 13:44, Tim Williams <[log in to unmask]> wrote: >> On Thu, Sep 2, 2010 at 4:18 PM, Mike Taylor <[log in to unmask]> wrote: >>> On 2 September 2010 18:12, Tim Williams <[log in to unmask]> wrote: >>>> I have this need to support complex boolean queries within a field. >>>> I'd like to not have to repeat the 'index relation' over and over >>>> within the statement. Rather, I'd like something like >>>> >>>> title = ((fish OR turtle) AND sea) - though, much more complex - >>>> and don't want to have to write: >>>> >>>> ((title = fish OR title = turtle) AND title = sea) >>>> >>>> Logically, it's just projecting the index and relation upon the >>>> enclosed terms. Before we depart from the CQL spec I thought I'd see >>>> if there was a way to get similar 'shortcutting' using build-in >>>> extension mechanisms? >>> >>> Although the formal specification of CQL stupidly prohibits this >>> useful and unambiguous syntax, most or maybe all actual >>> implementations support it -- certainly the C/C++ parser in YAZ, >>> CQL-Java, the Perl CQL::Parser and thr Ruby gem all do. Have you >>> tried just going ahead and doing it? If it's being rejected, what CQL >>> parser are you using? >> >> Thanks Mike, I've got a little ANTLR grammar internally that >> implements a version of CQL. This lack of index+relation projection >> is one of two areas that I've had to stray from the spec so far... the >> other is the limited support for proximity. > > If you're using ANTLR, does that mean you're in Java? If so, why not > just use CQL-Java instead of rolling your own? Yeah, I'm on the JVM. It's complicated and only somewhat reasonable I suppose but... o) I wanted freedom to easily break from the spec - I knew of the prox problem early on and figured others would come up. o) I need to do numerous translations to implementation grammars/objects - easily done with ANTLR Tree Grammars. o) It was easier than learning your api (documentation left me wanting) :( As I said, it's only somewhat reasonable:) It made sense at the time anyway. --tim