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Re: Variable references in path expressions

From: TAN Kuan Hui <kuanhui@xemantics.com>
Date: Sat, 30 Apr 2005 10:42:57 +0800
Message-ID: <000401c54d2e$5a58ca90$6402a8c0@pinecone>
To: "Michael Dyck" <jmdyck@ibiblio.org>, <www-ql@w3.org>

> > I am concern about evaluating only the rhs. The following
> > production shows that we can do something to the rhs of "/"
> > prior to evaluating the expression.
> >
> > [67]    PathExpr    ::=    ("/" RelativePathExpr?)
> >                                     | ("//" RelativePathExpr)
> >                                     | RelativePathExpr /* gn: leading-lone-slash */
> > [68]    RelativePathExpr    ::=    StepExpr (("/" | "//") StepExpr)*
> Why do you think these productions show that? It's the normalization
> and evaluation rules, not the grammar productions, that dictate
> whether we can "do something" to a StepExpr prior to evaluating the
> expression.
This is where I think our interpretation differs. I take it that you
are inferring from the normalization and evaluation rules as layout
in formal semantics. Now, I see those rules being manifested
depending on how the semantics of the expression is to be fullfilled.
If there is agreement on how $a/$b should be processed, then
those evaluation rules has to fine tuned accordingly.
If there is a will there is a way.

I suspect $a/$b is going to be a very common construct
the result however is going to catch a lot of people by surprise.
Its just going to take some explaining and whether it will be
convincing is entirely another matter.
Received on Saturday, 30 April 2005 02:43:07 UTC

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