Empty local name issue in N3

Dear all,


According to the N3 grammar, the local names should at least contain one
character:


qname
        cfg:matches
"(([A-Z_a-z\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u02ff\u0370-\u037d\u037f-\u1fff\u200c-\u200d\u2070-\u218f\u2c00-\u2fef\u3001-\ud7ff\uf900-\ufdcf\ufdf0-\ufffd\U00010000-\U000effff][\\-0-9A-Z_a-z\u00b7\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u037d\u037f-\u1fff\u200c-\u200d\u203f-\u2040\u2070-\u218f\u2c00-\u2fef\u3001-\ud7ff\uf900-\ufdcf\ufdf0-\ufffd\U00010000-\U000effff]*)?:)?[A-Z_a-z\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u02ff\u0370-\u037d\u037f-\u1fff\u200c-\u200d\u2070-\u218f\u2c00-\u2fef\u3001-\ud7ff\uf900-\ufdcf
\ufdf0-\ufffd\U00010000-\U000effff][\\-0-9A-Z_a-z\u00b7\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u037d\u037f-\u1fff\u200c-\u200d\u203f-\u2040\u2070-\u218f\u2c00-\u2fef\u3001-\ud7ff\uf900-\ufdcf\ufdf0-\ufffd\U00010000-\U000effff]*";


        cfg:canStartWith     "a", "_", ":".  # @@ etc unicode


However:

 - This is in contrast to Turtle, which should be a subset of N3.

 - Empty local names are commonly used, for example the object of
 rdfs:isDefinedBy

 - CWM and SPARQL do accept empty local names.


Proposal: Allow empty local names in N3


The use of empty local names was mentioned before by Luc Peuvrier on 7 Mar
2009 on this mailing list.
This mail was sent before but appeared to be 'unreadable'.


Kind Regards,

Boris De Vloed | Agfa HealthCare
Junior Software Engineer | HE/Advanced Clinical Applications Research

Quadrat NV, Kortrijksesteenweg 157, 9830 Sint-Martens-Latem, Belgium
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