- From: James Clark <jjc@jclark.com>
- Date: Wed, 24 Apr 2002 21:22:03 +0700
- To: Ashok Malhotra <ashokma@microsoft.com>, XML Schema Comments <www-xml-schema-comments@w3.org>
But if it is a user-derived simple type, then you have to inherit the lexical representation to value space mapping of the base type, since XML Schema provides no other way for a user to specify it. As for the builtin derived simple types, I thought there was a principle that derivation of the builtin simple types works no different from derivation of user-defined simple types. This seems to me to be essentially the same problem as R-89 http://www.w3.org/2001/05/xmlschema-rec-comments#pfiinteger and need fixing in the same way. --On 24 April 2002 06:34 -0700 Ashok Malhotra <ashokma@microsoft.com> wrote: > James: > I have come to the conclusion that when you derive a simple type you > should not inherit the lexical representation of the base type. If you > do, > you open your self to a host of problems which we can discuss another > time. > > Thus, simple type derivation merely gives you a new, more restricted > value > space. You can then go ahead an specify a lexical space for this > restricted > value space and specify a mapping from the lexical to the value space. > > If you look at it this way, nonPositiveInteger has a value space > consisting > of 0 and the negative integers. Its lexical space consists of 0 and > strings of digits preceded by a minus sign. > > All the best, Ashok > =========================================================== > > > -----Original Message----- > From: James Clark [mailto:jjc@jclark.com] > Sent: Wednesday, April 24, 2002 3:23 AM > To: XML Schema Comments > Subject: Is +0 a nonPositiveInteger? > > Is +0 allowed as a nonPositiveInteger? At the moment there's a > contradiction. 3.3.14.1 says "nonPositiveInteger has a lexical > representation consisting of a negative sign ("-") followed by a > finite-length sequence of decimal digits (#x30-#x39). If the sequence of > digits consists of all zeros then the sign is optional." This doesn't > allow > +0. On the other hand 0 is in the value space of nonPositiveInteger and > +0 > is a legal representation of ) in the lexical space of integer. > > Either > > (a) the prose in 3.3.14.1 needs fixing, or > > (b) the schema for schema needs to add a pattern facet to the definition > of > nonPositiveInteger that excludes +0 > > If you do (b), then you will probably want to fix nonNegativeInteger to > disallow "-0". However, at the moment there's no contradiction since the > prose for nonNegativeInteger allows "an optional sign" not just an > optional > positive sign. > > James > > > > >
Received on Wednesday, 24 April 2002 10:19:48 UTC