Re: RIF Minutes for 21-Aug-07-rif-minutes.html

Jos de Bruijn wrote:
>>>>>>>>> Axel: Strings with @ signs in RDF - will this be OK in the proposed 
>>>>>>>>> format for such literals?
>>>>>>> The original proposal was that the text type is a pair of lexical form 
>>>>>>> and language code. The XML syntax would use attributes for the language 
>>>>>>> code as normal. For the presentation syntax (but see below) I'd suggest 
>>>>>>> following N3/Turtle:
>>>>>>>
>>>>>>>             "string"@lang
>>>>>>>
>>>>>>> which would correspond to the literal value ("string", lang)^^rif:text.
>>>>>> For uniformity of the syntax, it is better to use "string@lang"^^...
>>>>>> where @ is special (i.e., needs to be escaped, if one wants to include it
>>>>>> in the string. 
>>>>>> By the way, why can't we use xsd:string data type for these?
>>>>> Because, in this case, it would be impossible to distinguish between
>>>>> strings with a '@', and strings with a language tag.
>>>> No. Read again about having @ a special symbol that needs to be escaped.
>>> So, you propose to always escape it? It seems that you would then change
>>> the xsd:string datatype, which is something we should avoid.
>> Perhaps using xsd:string is not the right way, since this type does not
>> have the language specifier (right?).  
> 
> Correct.
> 
>> So, we should use a different data
>> type. Perhaps rif:text or rif:istring. 
> 
> So we are in agreement.
> I sent an email to the XSD folks earlier, to see whether/how such a
> datatype could be aligned with the XML Schema datatypes.
> 
>> But the syntax should be uniform:
>> "...@lang"^^rif:text.  Inside the "..." the @ sign should be escaped if it
>> is not the language sign.
> 
> I have no problem with that; sounds reasonable.

In terms of the abstract syntax the rif:text datatype should have two 
components - the lexical form and the language tag.

This should be translated in the XML syntax to character content plus an 
xml:lang tag.

If there is some reason the BNF is clearer with this strange escaped-@ 
then I guess I won't oppose it but the BNF is not the important syntax. 
However, I would have thought it would be better to have the bit between 
the "..." correspond to the character content in the XML.

Dave
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Received on Tuesday, 28 August 2007 13:32:32 UTC