The theory of tree languages, founded in the late Sixties and still active in the Seventies, was much less active during the Eighties. Now there is a simultaneous revival in several countries, with a number of significant results proved in the past five years. A large proportion of them appear in the present volume. The editors of this volume suggested that the authors should write comprehensive half-survey papers. This collection is therefore useful for everyone interested in the theory of tree languages as it covers most of the recent questions which are not treated in the very few rather old standard books on the subject. Trees appear naturally in many chapters of computer science and each new property is likely to result in improvement of some computational solution of a real problem in handling logical formulae, data structures, programming languages on systems, algorithms etc. The point of view adopted here is to put emphasis on the properties themselves and their rigorous mathematical exposition rather than on the many possible applications. This volume is a useful source of concepts and methods which may be applied successfully in many situations: its philosophy is very close to the whole philosophy of the ESPRIT Basic Research Actions and to that of the European Association for Theoretical Computer Science.

This is the first book that provides a solid theoretical account of the foundation of the popular data format XML. Part I establishes basic concepts, starting with schemas, tree automata and pattern matching, and concluding with static typechecking for XML as a highlight of the book. In Part II, the author turns his attention to more advanced topics, including efficient 'on-the-fly' tree automata algorithms, path- and logic-based queries, tree transformation, and exact typechecking. The author provides many examples of code fragments to illustrate features, and exercises to enhance understanding. Thus the book will be ideal for students and researchers whether just beginning, or experienced in XML research.

This volume contains the proceedings of the 15th International Conference on Rewriting Techniques and Applications (RTA 2004), which was held June 2- 5, 2004, at the RWTH Aachen in Germany. RTA is the major forum for the presentation of research on all aspects of rewriting. Previous RTA conferences took place in Dijon (1985), Bordeaux (1987), Chapel Hill (1989), Como (1991), Montreal (1993), Kaiserslautern (1995), Rutgers (1996), Sitges (1997), Tsukuba (1998), Trento (1999), Norwich (2000), Utrecht (2001), Copenhagen (2002), and Valencia (2003). The program committee selected 19 papers for presentation, including?ve system descriptions, from a total of 43 submissions. In addition, there were invited talks by Neil Jones, Aart Middeldorp, and Robin Milner. Many people helped to make RTA 2004 a success. I am grateful to the m- bers of the program committee and the external referees for reviewing the s- missionsandmaintainingthehighstandardsoftheRTAconferences. Itisagreat pleasure to thank the conference chair Jurgen · Giesl and the other members of the local organizing committee. They were in charge of the local organization of all events partaking in the Federated Conference on Rewriting, Deduction, and Programming (RDP). Apart from RTA 2004, these events were: - 2nd International Workshop on Higher-Order Rewriting (Delia Kesner, Femke van Raamsdonk, and Joe Wells), - 5th International Workshop on Rule-Based Programming (Slim Abdennadher and Christophe Ringeissen), - 13thInternationalWorkshoponFunctionaland(Constraint)LogicProgr- ming (Herbert Kuchen), - IFIP Working Group 1.

This book constitutes the refereed proceedings of the 12th International Conference on Language and Automata Theory and Applications, LATA 2018, held in Ramat Gan, Israel, in April 2018.The 20 revised full papers presented together with 3 invited papers were carefully reviewed and selected from 58 submissions. The papers cover fields like algebraic language theory, algorithms for semi-structured data mining, algorithms on automata and words, automata and logic, automata for system analysis and programme verification, automata networks, automatic structures, codes, combinatorics on words, computational complexity, concurrency and Petri nets, data and image compression, descriptional complexity, foundations of finite state technology, foundations of XML, grammars (Chomsky hierarchy, contextual, unification, categorial, etc.), grammatical inference and algorithmic learning, graphs and graph transformation, language varieties and semigroups, language-based cryptography, mathematical and logical foundations of programming methodologies, parallel and regulated rewriting, parsing, patterns, power series, string processing algorithms, symbolic dynamics, term rewriting, transducers, trees, tree languages and tree automata, and weighted automata.

A step-by-step development of the theory of automata, languages and computation. Intended for use as the basis of an introductory course at both junior and senior levels, the text is organized so as to allow the design of various courses based on selected material. It features basic models of computation, formal languages and their properties; computability, decidability and complexity; a discussion of modern trends in the theory of automata and formal languages; design of programming languages, including the development of a new programming language; and compiler design, including the construction of a complete compiler. Alexander Meduna uses clear definitions, easy-to-follow proofs and helpful examples to make formerly obscure concepts easy to understand. He also includes challenging exercises and programming projects to enhance the reader's comprehension, and many 'real world' illustrations and applications in practical computer science.