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RE: The semantics of blank nodes

From: Jon Hanna <jon@spin.ie>
Date: Wed, 13 Nov 2002 16:40:21 -0000
To: <www-rdf-interest@w3.org>
Message-ID: <NDBBLCBLIMDOPKMOPHLHEEHEEJAA.jon@spin.ie>

1. You simply may not know (or have a vocabulary to express) the type.
2. You simply may not have a useful identifier.

You can still make use of what you do know though.

The semantics of a blank node convey certain information, and do so in a
manner compatible with statements not using blank nodes. Only if they failed
to do that could you say that the semantics were weakened.

Of course in the example:

<http://www.example.org/staffid/85740>
<http://www.example.org/terms/address>
_:johnaddress .

_:johnaddress
<http://www.example.org/terms/street>
"1501 Grant Avenue" .

It could perhaps be possible to add a type (perhaps from knowing the range
of <http://www.example.org/terms/address>, perhaps from elsewhere) and/or a
URI (perhaps from an unambiguous predicate). So even if your application
required the type or URI the above triples wouldn't necessarily be useless
once they have been merged with others.
Received on Wednesday, 13 November 2002 11:34:11 GMT

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