XRules is an XML business rules language that expresses constraints, calculations, interdependencies, and properties that describe and exist among elements and attributes of an XML document. XRules can be used to validate business rules in an XML transaction, attach metadata to the XML Infoset, or add dynamism to XML by using the Dynamic DOM.
Behaviour-driven development is an “outside-in” methodology. It starts at the outside by identifying business outcomes, and then drills down into the feature set that will achieve those outcomes. Each feature is captured as a “story”, which defines the scope of the feature along with its acceptance criteria. This article introduces the BDD approach to defining and identifying stories and their acceptance criteria.
B. Nuseibeh. ICSE-2001 International Workshop: From Software Requirements to Architectures (STRAW-01), Toronto, Canada, (September 2001)See also Twin Peaks IEEE Computer version.