In external-data-entity
rules, the attributes of the entity that triggered the rule are referred to using the attribute
herald.
Entities named in ENTITY and ENTITIES attributes may also have data attributes. You can use the data-attribute
operator to access these data attributes.
The keyword data-attribute
can be used in the same way that attribute
is used elsewhere. The data attribute name must always be followed by of
and, in parentheses, the identification of the attribute value or item containing the entity name.