Context Sequence Matching for XML

Context and sequence variables allow matching to explore term-trees both in depth and in breadth. It makes context sequence matching a suitable computational mechanism for a rule-based language to query and transform XML, or to specify and verify web sites. Such a language would have advantages of both path-based and pattern-based languages. We develop a context sequence matching algorithm and its extension for regular expression matching, and prove their soundness, termination and completeness properties.