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Re: Hierarchical query

From: Aloha Kakuikanu <aloha.kakuikanu_at_yahoo.com>
Date: Thu, 14 Jun 2007 18:32:42 -0000
Message-ID: <1181845962.714746.55010@z28g2000prd.googlegroups.com>


On Jun 14, 10:14 am, Jan Hidders <hidd..._at_gmail.com> wrote:
> On 14 jun, 19:54, Vadim Tropashko <vadimtro_inva..._at_yahoo.com> wrote:
>
> > On Jun 14, 10:35 am, Jan Hidders <hidd..._at_gmail.com> wrote:
>
> > > On 14 jun, 18:41, Vadim Tropashko <vadimtro_inva..._at_yahoo.com> wrote:
> > > > I was going to define tree query in pure language settings, be it
> > > > regular languges, context free grammars, or else.
>
> > > ?? How does one query a set of strings in a "pure language setting"?
> > > Of course you might select certain strings from the set with something
> > > that accepts strings from a certain language, but that is clearly
> > > inadequate because you cannot take the "context" of the node into
> > > account.
>
> > And what the node's "context" would be?
>
> The nodes around it, the preceding siblings, the following sibling, et
> cetera. How do I ask for an "a" node that is immediately preceded by a
> "b" node?

No you don't need that many, only two. One is the absolute position of the node in the hierarchy, for example path, or 4 integers corresponding to the matrix encoding. The second one is the node payload -- grammar token in this case. They have completely different structure, so I'm most likely wrong expecting to be able to operate a single attribute. Received on Thu Jun 14 2007 - 13:32:42 CDT

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