In his XML-DEV announcement, James Clark noted that the RELAX NG Technical Committee have allocated two months for public comment and implementation of the 0.9 specification, ending on the 10th October. The intention is to release version 1.0 following the resolution of feedback gathered during that time.

Alongside the updated RELAX NG tutorial, the editors have published a DTD Compatibility Annotations working draft. This specification builds on the RELAX NG annotation mechanism to provide support for some DTD features which are not otherwise catered for. Initially this list includes attribute default values, ID/IDREF constraints and documentation embedded in a schema.

Interestingly the annotations document demonstrates a clean separation between infoset modification and validation:

Most of the features of XML 1.0 DTDs that are not supported by RELAX NG involve modification to the infoset. In XML 1.0, validation and infoset modification are combined in a monolithic XML processor. It is a goal of this specification to provide a clean separation between validation and infoset modification, so that a wide variety of implementation scenarios are possible.

Comments on the specification, tutorial and annotations documents should be directed at the relax-ng-comment mailing list (archives).

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