How does the BNML Schema work?

The core of the BNML Schema is a very small number of elements to model the generic structure of almost any kind of narrative document. To begin, an author only needs to know 6 or 7 elements.

The BNML Schema uses a single, recursive element (item) to define the main parts, such as sections or clauses in the document to any desired level. The item element may have a number (num) and a title. The title is not required.

The item element is intended to be a re-usable object that can be inserted at any point into the document hierarchy.

The BNML Schema also defines a strict conceptual or grammatical paragraph using a block element. All lists, tables, graphic objects and inline content must be contained by a block element. Lists are created by re-using the item element inside block. The block element does not contain mixed content but uses the text element for all narrative content.

The Schema defines a set of standard structure patterns for the occurrence of item and block elements within container elements. Schema designers can easily select the desired pattern for each container. In addition to block only or item only structures, the defined patterns are:

• Tight structure model which permits either item or block elements but does not allow both at the same level;
• Standard structure model which permits block before the first item, but not otherwise at the same level; and
• Loose structure model which allows item and block to be mixed at the same level.

An inclusion element is used to represent all content that occurs within the narrative but is distinct from the surrounding text, such as quotations, explanatory notes and examples. It may also be used for graphics and tables which require group titles or figure or table numbers. The function of each inclusion element is determined by the value of its class attribute.

These core elements and patterns can be used inside other container elements that are needed to define the generic structure of particular document types such as document, contract, correspondence and item.

An adjunct element is used for subsidiary content such as schedules, appendices and attachments. The adjunct may contain complete documents or item and block markup.

The BNML Schema also provides specialist markup for particular document types, including the party-signature markup for use in contracts and correspondence.

Once these basic principles are understood, an author is able to markup narrative content of any complexity. The Elkera BNML Schema can markup something as simple as a few paragraphs in a letter or as complex as a technical specification or a lengthy, contract with complex numbered clauses and schedules.