- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Sun, 5 Sep 2010 22:23:48 +0100
- To: nathan@webr3.org
- Cc: Manu Sporny <msporny@digitalbazaar.com>, RDFa WG <public-rdfa-wg@w3.org>, Sebastian Heath <sebastian.heath@gmail.com>
On 5 Sep 2010, at 20:18, Nathan wrote:
> this:
>
> <span property="foo:bar">{$templatevar}</span>
>
> is just as likely as this:
>
> <span property="foo:bar" content="{$templatevar}" ...
No, they are not equally likely. The second is for the case where the
user-visible string has to be different from the machine-visible
string. That is not the common case. Also, less sophisticated authors
are much more likely to use the first pattern, and they are the ones
we need to worry about here -- the ones who are likely to forget about
zero-length literals and similar corner cases.
But given that @content="" can also occur accidentally, if you have
another idea how to express the empty string in a way that is less
likely to be authored by accident...?
> generally it's going to be programmers who write the scripts that
> consume / process RDFa and if they feel like adding a line that
> throws away all triples with empty elements then it's hardly a big
> job.
I don't like this attitude. As a consumer of RDFa data I shouldn't
have to guess wether the RDFa author meant to have that zero-length
string or wether they just didn't know what they were doing.
> note:
> I'd hope that we'll all be moving to including datatype restrictions
> in ontologies in the near future which will cover whether a given
> value is valid for a given property or not, perhaps this along with
> processors which understand restrictions is the long-term-fix that
> addresses this and similar issues.
Well I agree, but that's at best a long-term hope and not something
that can be addressed now in RDFa.
Richard
Received on Sunday, 5 September 2010 21:24:25 UTC