built-in entity
The #implied keyword is used as an element, a group, and an external entity in an OmniMark
program. Each will be discussed in turn.
When #implied is used in place of an element name in a rule, that rule applies to all elements
not accounted for by other rules. Also, #implied is used when the programmer does not know the names
of all the elements that will appear (for example, when an OmniMark program is applied to SGML or XML documents
with different DTDs).
When used as a group, the #implied group is always active. When an OmniMark program starts, it is
the only group that is active. All rules before the first explicit group declaration are considered
part of the #implied group, as are all rules in a program with no explicit group
declaration. The #implied group cannot be combined with other groups in group
declarations because it essentially includes all groups. A rule in the #implied group is always
active.
Similarly, when #implied is used in place of an entity name in
an external-text-entity or external-data-entity rule, that rule applies to all such
entities not matched by other rules.