This is a version class definition of a three-tier document structure for holding schema data.
The primary interface for this class is ISPFTEFSchemaDocVersion, which is described below. As well as realizing this interface, the other interfaces that are realized by this class definition are the standard version interfaces such as ISPFDocumentObject, ISPFDocumentVersion, ISPFNonPublishedDocVersion, ISPFExportableItem, ISPFFileComposition, and ISPFOwnedObj.