| Enumeration | Description | |
|---|---|---|
 | AttributePresence | Defines the different constraints on an attribute's presence on an element. |
| AttributeType | Defines the different possible attribute types. |
| DeclaredContent | Where nested subelements cannot occur within an element, its contents can be declared to consist of one of the types of declared content contained in this enumeration. |
| GroupType | The type of the content model group, defining the order in which child elements can occur. |
| Occurrence | Qualifies the occurrence of a child element within a content model group. |
| WhitespaceHandling | Specifies how white space is handled. (Not defined in PORTABLE framework, so we added it here). |