- From: Dave Beckett <dave@dajobe.org>
- Date: Sat, 07 Jan 2006 20:01:40 -0800
- To: Dan Connolly <connolly@w3.org>
- CC: public-rdf-dawg-comments@w3.org
Dan Connolly wrote: > On Sat, 2006-01-07 at 12:38 -0800, Dave Beckett wrote: > >>SPARQL refers to: >> >>[[ >> [UNICODE] >> The Unicode Standard, Version 4. ISBN 0-321-18578-1, as updated from >> time to time by the publication of new versions. The latest version of >> Unicode and additional information on versions of the standard and of >> the Unicode Character Database is available at >> http://www.unicode.org/unicode/standard/versions/. >> >>]] >> >>which cites a moving target. Please define SPARQL in terms of a >>particular version of Unicode only, and no other. Otherwise if or when >>this Unicode consortium makes some incompatible changes, all existing >>implementations become invalid. > > > How so? How is conformance to SPARQL sensitive to changes in Unicode? The SPARQL query syntax is defined on Unicode characters: [[ A. SPARQL Grammar A SPARQL query string is a Unicode character string (c.f. section 6.1 String concepts of [CHARMOD]) ... ]] although the grammar defines precise ranges of codepoints for particular things such as names of variables (based on XML 1.1 I think). If the definition of a Unicode character string changes in some future Unicode revision, such as for example by allowing additional codepoints, then there will be additional codepoints allowed in a SPARQL query string, following the sentence above. Any part of the grammar that uses an negated range such as with '[^...]' will allow such codepoints. Examples include: http://www.w3.org/TR/rdf-sparql-query/#rQ_IRI_REF and all string literals. These codepoints may be refused by something implementing Unicode 4.0 and no more. Dave
Received on Sunday, 8 January 2006 04:02:02 UTC