Should I use XSD 1.1 to create an open standard?

Question

We were asked to compile a set of schemas for the open XML standard.

XSD 1.0 will handle most of the rules, but it will be a little messy in places (especially to ensure extensibility), it will also rely on artists reading free text descriptions of some rules in the form of annotations.

Almost all of the rules can be implemented using XSD 1.1, but we are not sure that this will be excessively limited.

So my question is: is XSD 1.1 enough for use in the wild?

Answer 1

Reasons to use XSD 1.0

• Argument with the least restrictive requirement: Maximize interaction between systems and teams by requiring the lowest common XSD 1.0 denominator standard.
• Extended support for tools and libraries: JAXB and xsd.exe (.NET), for example, still do not support XSD 1.1.

Reasons to use XSD 1.1

• Assertions ( xs:assert ) are superbly powerful. Uses XPath to provide a flexible mechanism for expressing constraints beyond core content and type.
• Assigning a conditional type can be useful when the type needs to change for the value of the attribute.
• Many other improvements. See W3C XML Schema Definition (XSD) Section 1.1. Part 1: Structures, Appendix G Changes from Version 1.0 (non-normative)

Recommendations

If all parties involved in creating and interacting with your system are willing to upgrade to XSD 1.1 and are not dependent on tools or libraries that support XSD 1.0, go to XSD 1.1. Otherwise, stick to XSD 1.0.