- From: Xan Gregg <xan.gregg@jmp.com>
- Date: Thu, 1 Apr 2004 09:21:55 -0500
- To: www-xml-schema-comments@w3.org
- Cc: Mary Holstege <holstege@mathling.com>, Dave Peterson <davep@iit.edu>
Definition of {facets} in 4.1.2.1 Derivation by restriction:
{facets} The union of the set of Facets (§2.4) components
resolved to by the facet [children] merged with {facets}
from {base type definition}, subject to the Facet
Restriction Valid constraints specified in Facets (§2.4).
What is being "unioned" and how does "merge" work? For example, if the
base has a minLength facet with value 5 and the derived type has a
minLength child facet of value 7, how many minLength facets are in the
derived type's facets property?
The text above makes it sound like both are present, but constraints
within the rec strongly imply there is only one facet for each facet
name. (For instance, reference to "*the* minLength facet" for
validation constraints). Common sense suggests the last facet of a
given name wins, but it's hard to get that from "union" and "merge".
Related member-only thread: Facet equality: questions/issues
http://lists.w3.org/Archives/Member/w3c-xml-schema-ig/2004Mar/0187.html
xan
Received on Thursday, 1 April 2004 09:22:23 UTC