The elements that define elements, attributes, and entities could contain several kinds of descriptive information for use by developers and authoring tools. While this representation may be mapped to a DTD using SGML syntax, SGML applications are currently unable to perform such mapping. This representation is more verbose than the current syntax. This representation's extensibility would lead to DTDs which could only partially be mapped to SGML syntax. There may be varying interpretations of the proper use and naming of elements and attributes for this purpose.
All names are subject to change pending the discovery of more appropriate terms.
This element could also contain further element and attribute elements if that seemed appropriate. At present, the XML 1.0 syntax for content models seems more flexible, especially for representing complex content models. Because of the collapsing of syntax performed by this representation, there may no longer be a good reason to maintain this distinction apart from backward compatibility. Using XML notation for entity declarations makes it much easier to create sets of large entities in a document. This is a sample entity.