Re: A question for RDF parser implementers - whitespace

Graham,

I ran those test cases and found that

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   " .
]]

entails

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces 
"^^<http://www.w3.org/2001/XMLSchema#string> .
]]

but that

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   "@en .
]]

does *not* entail

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces 
"^^<http://www.w3.org/2001/XMLSchema#string> .
]]

and that

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   "@en-US .
]]

does *not* entail

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   "@en-GB .
]]

and that

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   "@en-GB .
]]

does *not* entail

[[
@prefix dc:      <http://purl.org/dc/elements/1.1/> .
@prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix :        <#> .

<http://www.example.org/>
      dc:title "  The trouble with spaces   " .
]]

:)

-- 
Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/




Graham Klyne <gk@ninebynine.org>
Sent by: www-rdf-interest-request@w3.org
11/07/2004 12:39

 
        To:     Damian Steer <damian.steer@hp.com>
        cc:     www-rdf-interest@w3.org
        Subject:        Re: A question for RDF parser implementers - whitespace



At 10:10 11/07/04 +0100, Damian Steer wrote:

>On 9 Jul 2004, at 14:09, Graham Klyne wrote:
>
>>
>>Hmmm.  Let's try a test case.
>>
>>Does this:
>>
>>      <dc:title>  The trouble with spaces   </dc:title>
>
>...
>
>>
>>RDF-entail this:
>>
>>      <dc:title 
>> rdf:datatype="http://www.w3.org/2001/XMLSchema#string">  The trouble 
>> with spaces   </dc:title>
>
>...
>
>>I think it should, but under your suggested regime I think it would not.
>
>I think the specs support Norm's regime here. Try this:
>
><dc:title xml:lang="en"> The trouble with spaces </dc:title>
>
>A reasonable extension of your inference would give:
>
><dc:title xml:lang="en" 
>rdf:datatype="http://www.w3.org/2001/XMLSchema#string">  The trouble with 
>spaces   </dc:title>

(Ignoring the language tags) I would not accept that as an expected 
entailment.  They are different string values.

>But (strangely, I confess) the latter is invalid rdf: only plain literals 

>can have langs.
>
>So you either maintain the orthogonality of plain- and 
datatyped-literals, 
>or you get a weird restriction on rdf entailments ("...except for 
>lang-tagged literals").

I would also say that the entailment does not hold for the same string 
with 
different language tags, or with- and without- a language tag.

#g


------------
Graham Klyne
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Received on Sunday, 11 July 2004 07:29:51 UTC