Unambiguity of SGML Content Models - Pushdown Automata Revisited

Abstract

s and 1/TechReports/FullText Via WWW: URL http://www.informatik.uni-trier.de/Reports/List Via email: Send a mail to [email protected], subject 'MAIL ME CLEAR', body 'TechReports.HowTo' followed by an empty line, for detailed instructions Printed copies: Trierer Forschungsberichte Fachbereich IV - Mathematik / Informatik Universitat Trier .. D-54286 Trier ISSN 0944-0488 Forschungsbericht Nr. 97--05 Unambiguity of SGML Content Models -- Pushdown Automata Revisited Andreas Neumann Unambiguity of SGML Content Models -- Pushdown Automata Revisited Andreas Neumann Abteilung Informatik Universitat Trier 54286 Trier, Germany E-Mail: [email protected] March 24, 1997 Abstract We consider the property of unambiguity for regular expressions, extended by an additional operator &. It denotes concatenation in any order, and must have arbitrary arity since it is not associative. This extension gives us high succinctness in expressing equivalent regular expressions wit..