SBVR11 — Placeholder concepts model SBVR Structured English syntax

In clause 8.3.4 of SBVR v1.0, the concepts: 'placeholder has starting character position' and 'placeholder uses designation' model the syntax of the non-normative Structured English language described in Annex C of the spec. These may not be properties of the syntax of other vocabulary and rules languages, and are unsuitable for graphical languages.

The abstract syntax of any such language must be that a placeholder is an expression and must be unique within the fact type form. These requirements should be stated in the definition of placeholder. The placeholder expression is a designation for the role that is used only in definitions of the fact type, and its forms and roles.

The idea of its "character position" is meaningless in graphical languages. The idea specified in 'placeholder uses designation' is a language convention that is not consistently used in SBVR and may well be different in other languages. The semantics of that syntactic construct is captured by 'role ranges over object type' in 8.1.1. Any convention for the syntax used by a tool is out of scope for SBVR. Therefore, both of these fact types should be deleted from the normative specification.

The use of a starting character position to locate a placeholder within a fact type form is meaningful only for fact type forms whose expressions are sequences of characters. Business vocabularies are generally defined using such expressions and so are SBVR’s own vocabularies. However, fact types can be represented by expressions that are not sequences of characters. SBVR provides a reference scheme only for placeholders in fact type forms that are sequences of characters. SBVR does not prohibit use of other reference schemes for placeholders, nor does it prohibit nontextual fact type forms.
The text is revised to add clarifying notes regarding textual fact type forms. Also, the definition of ‘placeholder uses designation’ is modified.