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Predicates

From: Cliff Binstock <binstock@pacifier.net>
Date: Tue, 26 Feb 2002 18:38:05 -0500 (EST)
Message-ID: <018401c1bf1e$b64b5940$290d2b42@moomoo>
To: <www-xpath-comments@w3.org>
To all,

I would like to recommend a minor wording addition with
respect to predicates.  Let me start by saying I have read
the 1.0 rec quite a few times, and missed a crucial point.

I just read the 2.0 section of the recommendation that
refers to "Predicates" this section is clearer, although
I had 20-20 vision coming in :)

Specifically, after a detailed discussion with
Jeni Tennison (thanks Jeni!), It finally "clicked" that
the predicate filters (despite the actual use of the
word "filter").

Jeni specifically wrote:

>> When you use a predicate, you filter a node set - the node set
>> still returns the same kind of node as it would without the
>> predicate, but returns only some of those nodes.

This *really* helps!  I think I might further the discussion by saying
that not only does it return "the same kind of node", but a predicate
returns a "subset of the nodes" specified by the expression without
the predicate.

Finally, while I realize this appears trivial, it might truly help to create
another paragraph.  In the 1.0 and 2.0 text, the reader jumps from
the "filter" discussion *directly* into how the Boolean result is treated,
in the same paragraph.  I think I (repeatedly) lost the important context
because I got bogged down in the discussion of the Boolean coercion,
which is more of a 'how' than the 'what' that I missed.

Thanks for listening (as if you had much choice)!

Also, FYI, the e-mail for this group in the 2.0 doc is not a hyperlink;
it should be.

Cliff Binstock
binstock@pacifier.net
Received on Wednesday, 27 February 2002 03:00:37 GMT

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