FOSI Support for DITA Document Types
The FOSI formatting engine allows a FOSI stylesheet to style both base and specialized elements in DITA document types. A specialized DITA document type can use a FOSI developed for the base document type without change, or a FOSI can be developed to apply formatting to new specialized elements. Note that when using FOSI-based composition, both fallback generalization and FOSI base e-i-c matching occur. However, fallback generalization occurs first, so generally takes precedence.
When matching a DITA specialized element to FOSI formatting specifications, the DITA element can match its FOSI specifications directly and also match the FOSI specifications for the base elements used for its specialization. A specialized element cannot match FOSI specifications for an element that is more specific than, and based on, itself.
For example, assume progtitle specializes reftitle and reftitle specializes title. The specialized “prog” DTD would contain:
<!ATTLIST progtitle class CDATA "- topic/title ref/reftitle prog/progtitle">
where
class is defined as the
ditaSpecializationAttribute in the
Options element of the document type configuration (
.dcf) file. See
Specifying the DITA specialization attribute for the DCF file setup information.
If reftitle is styled explicitly in the FOSI, for example,
<e-i-c gi="reftitle"> ... </e-i-c>,
then its style properties can apply to both reftitle and its specialization, progtitle, but cannot apply to title.
Matching an e-i-c to an element is determined by several factors, each of which is detailed in the sections that follow. The factors include:
• Priority
• Occurrence
• Specval