Tags
Most of the information in an PTC Arbortext Layout Developer template or document is contained in an PTC Arbortext Layout Developer tag. The only exceptions are preferences, document pages, and JavaScript objects, which are not considered content.
Tags can be described as separate files within the PTC Arbortext Layout Developer document. A two character file extension identifies a tag and allows tags to be grouped by type.
There are currently 85 PTC Arbortext Layout Developer tag types, each with a specific role and behavior in PTC Arbortext Layout Developer. It is common to access about a quarter of these tag types — others are created through the JavaScript interface or by other PTC Arbortext Layout Developer processes.
Tags have a name and an extension that indicates the tag type. The extension is a two character suffix following a full stop at the end of the name, for example .tx. The tag name can be up to 48 characters in length, not including the extension or the namespace part of the tag’s identifier. Tag names follow similar rules to those used to define XML and SGML element names. The exception is that PTC Arbortext Layout Developer tag names can start with a / character to allow them to match with closing elements in markup.
Some tags can be grouped:
• Tags that hold text content
Text streams (.tx), XML streams (.xm), and XML DOMs (.xd) hold text and XML content.
• Tags that hold styling information
Styling can be defined in tags such as styles (.st) and references (.rf). Note that these tag types are now more often used to hold PTC Arbortext Layout Developer’s proprietary processing instruction styling code. Styling is now increasingly applied through JavaScript.
• Script tags
Script tag types exist for each of the languages supported by PTC Arbortext Layout Developer including JavaScript (.jf and .js), perl (.pl), and PTC Arbortext Layout Developer’s traditional macro-based scripts (.sc).
• Graphic tags
There are two types of graphic: raster graphics (.rg — bitmaps) and object graphics (.og — vectors). It is also possible to create an SVG in an XML tag and convert it dynamically to a graphic.
• Control stream tags
Control streams provide PTC Arbortext Layout Developer with information on how to handle certain formatting features or to draw certain objects. Control streams exist for index and footnote definitions, frames and layers, rules and colors, context matching controllers and page sequence controllers.
• Generated content tags
Generated content tags exist for items such as indexes (.ix), footnotes (.xf), and checksum reports (.ck).
• Miscellaneous tags
Some user tags have no real purpose other than the storage of information.
Almost all tag types can be edited in the PTC Arbortext Layout Developer interface. Some tags are protected and some, such as graphics, are not available for editing. The PTC Arbortext Layout Developer interface has tools for managing tags. It is simple to browse the tags in a document to find one for edit.
Tags can be either a saved part of the document or linked to the document. Most tags are part of the document or template. Linking allows users to share tags between documents or to avoid creating a very large document, for example by linking graphics.
The Content group of Formatting Object Model (FOM) objects represent the majority of the tag types. Many of them inherit the properties and methods of the
fTag object, which is one of the fundamental FOM objects. Refer to
Overview of the Formatting Object Model for information.
Best Practices
• Refer to PTC Arbortext Layout Developer tags as tags. Refer to XML markup as elements in the context of PTC Arbortext Layout Developer to avoid confusion.
• Use tags with the / prefix to match the closing elements in SGML and XML.