Re: XSD simpleType with final = extension

Hi all,
   It seems very clear to me that, within XML Schema 1.1 spec, simpleType
definition allows 'extension' as a value of 'final' attribute.

With regards to XML Schema 1.0 structures spec, following are the relevant
phrases mentioned within the spec,

<quote>

3.14.2 (non-normative) XML Representation of Simple Type Definition Schema
Components

XML Representation Summary: simpleType Element Information Item

<simpleType
  final = (#all | List of (list | union | restriction))
  id = ID
  name = NCName
  {any attributes with non-schema namespace . . .}>
  Content: (annotation?, (restriction | list | union))
</simpleType>

3.4.6 Constraints on Complex Type Definition Schema Components

Schema Component Constraint: Derivation Valid (Extension)

If the {derivation method} is extension, the appropriate case among the
following must be true:
1 If the {base type definition} is a complex type definition, then all of
the following must be true:
  ......
  ......

2 If the {base type definition} is a simple type definition, then all of
the following must be true:
2.1 The {content type} must be the same simple type definition.
2.2 The {final} of the {base type definition} must not contain extension.

</quote>

From the prose mentioned within the XML Schema 1.0 structures spec, as
quoted above, although section "3.14.2 (non-normative) XML Representation
of Simple Type Definition Schema Components" doesn't mentioned 'extension'
as a possible value of 'final' attribute of simpleType (that is a bug in
the spec according to me), but the prose within the section "3.4.6
Constraints on Complex Type Definition Schema Components", clearly seems to
define semantics of value 'extension' of the simpleType's attribute 'final'.

As stated earlier within this thread, there's microsoft test case within
W3C XSD 1.0 test suite, that indicates, that 'extension' is a possible
value of simpleType's attribute 'final'. I could verify within Saxon's XSD
1.0 and 1.1 processors, and that allows 'extension' as value of
simpleType's attribute 'final'.

Yesterday, we modified Apache Xerces's XSD 1.0 and 1.1 processor's source
code, to allow 'extension' as possible value of simpleType's attribute
'final'.

On Sun, Mar 6, 2022 at 9:06 PM Michael Kay <[email protected]> wrote:

> Following the paper trail on this leads to
>
> https://www.w3.org/Bugs/Public/show_bug.cgi?id=5783
>
> which is a bug against XSD 1.0 that was never resolved. So I think the
> answer to your question is that it's a known bug in the spec.
>
> In most cases, but perhaps not all, when there's a known bug in XSD 1.0,
> consulting XSD 1.1 will give you the preferred resolution.
>
> Michael Kay
> Saxonica
>


-- 
Regards,
Mukul Gandhi