- From: Michael Kay <mike@saxonica.com>
- Date: Mon, 16 Jan 2012 20:56:13 +0000
- To: www-xml-schema-comments@w3.org
>Still if one could find out what the reasons might be, and if none were found to be that serious, one could perhaps have more lenient parsers get rid of those whitespaces in the context of RDF/XML. The XSD 1.1 specification allows vendor-defined facets, and the Saxon engine has exploited this facility to define a facet saxon:preprocess that allows preprocessing of the value appearing in the instance document before validation starts (by means of an XPath expression). So you could define <saxon:preprocess action="translate($value, '  ', '')"/>. See http://www.saxonica.com/documentation/schema-processing/extensions11/preprocess.xml Technically this is a "pre-lexical" facet in that, like xs:whiteSpace, it defines processing that takes place before the lexical value is materialized. Other uses include allowing continental European number formats, or normalizing case prior to validation using an enumeration facet; it could also be used to permit the values "yes" and "no" for an xs:boolean. Of course, a solution that only works in one processor is not very practical for most XSD users. But the experience with XSLT was that allowing vendors to make extensions of this kind stimulated other vendors to copy the more popular extensions, leading to the emergence of de-facto standard extensions which are then primary candidates for incorporation in a future version of the standard. Michael Kay Saxonica
Received on Monday, 16 January 2012 20:56:38 UTC