2 Terms and Concepts

Some special terms are defined here in order to clarify their relationship to similar terms used in the technologies on which the xpointer() scheme is based. Additional terms specific to the xpointer() scheme are defined in the flow of the text. Refer to [XPath], [DOM2], [Infoset], and [RFC 2396] for definitions of other technical terms used in this specification.

point

A location in an XML Information Set with no content or children. For example, the location between two adjacent nodes, or after a particular character within a text node. This notion is defined fully later (see point), and comes from the DOM Level 2 [DOM2] specification's notion of positions; this specification refers to such positions by the term "point" to avoid confusion with XPath positions.

range

An identification of all the XML Information Set content between a pair of points. This notion is defined fully later (see range), and comes from the DOM Level 2 [DOM2] specification.

[Definition: location]

A generalization of XPath's node that includes points and ranges in addition to XPath nodes (which include the 7 node types defined by the XML Information Set.[Infoset]

[Definition: location-set]

An unordered list of locations, such as produced by an xpointer() scheme expression. This corresponds to the node-set that is produced by XPath expressions, except for the generalization to include points and ranges. Just as for an XPath node-set, a location-set is unordered, but can be treated as having a specific order depending on the axis that is operating on it. In this specification, the ordering depends on the notion of document order defined in4.4.5 Document order, which applies to point and range locations as well as nodes, rather than on XPath's treatment of document order for nodes.