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Example Errors

From: Ryan Levering <RRLevering@yahoo.com>
Date: Fri, 2 Sep 2005 19:17:29 -0400
To: <public-rdf-dawg-comments@w3.org>
Message-ID: <97C9F8341808C244BFF39DCB6EDD5AD71116EA@server.home.ryan.levering.name>
I never got around to giving more in-depth thoughts on the document.  Even
though technically the deadline is passed for public comments, I thought I
should at least mention that several examples in the value testing section
are objectively incorrect, regardless of when comments are due :).

The first example in for sop:RDFterm-equal should have two results
in the query results section, with the inverse solution as well as the
listed, since name1=>Ms A. and name2=>Alice is just as valid a binding.

The second example in has a typo, the time in the data should be
19:00, not 19:01 like listed, to get the results expected.

The first example in has several problems, so it's best to
re-examine it.  Namely, the FILTER construct is missing a parenthesis (or
should have the outside one removed) and the example appears to be
projecting an undefined variable for no reason.

The second example in should have foaf:givenName as the predicate,
not foaf:name.

The query under section 11 Testing Values should probably read "?date > ..."
and not "?date < ...".  Otherwise, the same result will be returned in both
examples, since neither of the dates in the data will test true, no matter
whether the casting works or not.

The example in should read "FILTER regex(?name...", not "FILTER

This may actually present some issues in general, but example has a
statement ""FILTER (lang(?name) = "ES" ) )"".  Technically, "ES" will parse
to a untyped literal and the LANG function returns a xsd:string, which will
by the constraints of the language result in a literal compare, which will
fail in all cases.  To be technically accurate, it should read ""FILTER
(lang(?name) = str("ES") ) )"".

Section 10.2 has a typo in the query - "?name X" should have the space

In section 9.3, the default graph should actually be a named graph with the
uri http://example.org/dft.ttl.

In section 9.1, the default graph should actually be a named graph with the
uri http://example.org/foaf/aliceFoaf.

In section 8.4, the example is fairly confusing since the named graphs have
different names than what they are called in the default graph.  This may be
purposeful, as they might dynamically evaluate to the named graphs, but it's
still a bit confusing.

While I'm at it, I'll throw in a question: what's the difference between STR
function and xsd:string cast constructor?  They seem redundant.

Ryan Levering
Received on Friday, 2 September 2005 23:22:29 UTC

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