A term rewrite system framework for code carrying theory

Picci, P. (2011). A term rewrite system framework for code carrying theory. http://hdl.handle.net/10251/11146.Archivo delegad

Programming and symbolic computation in Maude

[EN] Rewriting logic is both a flexible semantic framework within which widely different concurrent systems can be naturally specified and a logical framework in which widely different logics can be specified. Maude programs are exactly rewrite theories. Maude has also a formal environment of verification tools. Symbolic computation is a powerful technique for reasoning about the correctness of concurrent systems and for increasing the power of formal tools. We present several new symbolic features of Maude that enhance formal reasoning about Maude programs and the effectiveness of formal tools. They include: (i) very general unification modulo user-definable equational theories, and (ii) symbolic reachability analysis of concurrent systems using narrowing. The paper does not focus just on symbolic features: it also describes several other new Maude features, including: (iii) Maude's strategy language for controlling rewriting, and (iv) external objects that allow flexible interaction of Maude object-based concurrent systems with the external world. In particular, meta-interpreters are external objects encapsulating Maude interpreters that can interact with many other objects. To make the paper self-contained and give a reasonably complete language overview, we also review the basic Maude features for equational rewriting and rewriting with rules, Maude programming of concurrent object systems, and reflection. Furthermore, we include many examples illustrating all the Maude notions and features described in the paper.Duran has been partially supported by MINECO/FEDER project TIN2014-52034-R. Escobar has been partially supported by the EU (FEDER) and the MCIU under grant RTI2018-094403-B-C32, by the Spanish Generalitat Valenciana under grant PROMETE0/2019/098, and by the US Air Force Office of Scientific Research under award number FA9550-17-1-0286. MartiOliet and Rubio have been partially supported by MCIU Spanish project TRACES (TIN2015-67522-C3-3-R). Rubio has also been partially supported by a MCIU grant FPU17/02319. Meseguer and Talcott have been partially supported by NRL Grant N00173 -17-1-G002. Talcott has also been partially supported by ONR Grant N00014-15-1-2202.Durán, F.; Eker, S.; Escobar Román, S.; NARCISO MARTÍ OLIET; José Meseguer; Rubén Rubio; Talcott, C. (2020). Programming and symbolic computation in Maude. Journal of Logical and Algebraic Methods in Programming. 110:1-58. https://doi.org/10.1016/j.jlamp.2019.100497S158110Alpuente, M., Escobar, S., Espert, J., & Meseguer, J. (2014). A modular order-sorted equational generalization algorithm. Information and Computation, 235, 98-136. doi:10.1016/j.ic.2014.01.006K. Bae, J. Meseguer, Predicate abstraction of rewrite theories, in: [36], 2014, pp. 61–76.Bae, K., & Meseguer, J. (2015). Model checking linear temporal logic of rewriting formulas under localized fairness. Science of Computer Programming, 99, 193-234. doi:10.1016/j.scico.2014.02.006Bae, K., Meseguer, J., & Ölveczky, P. C. (2014). Formal patterns for multirate distributed real-time systems. Science of Computer Programming, 91, 3-44. doi:10.1016/j.scico.2013.09.010P. Borovanský, C. Kirchner, H. Kirchner, P.E. Moreau, C. Ringeissen, An overview of ELAN, in: [77], 1998, pp. 55–70.Bouhoula, A., Jouannaud, J.-P., & Meseguer, J. (2000). Specification and proof in membership equational logic. Theoretical Computer Science, 236(1-2), 35-132. doi:10.1016/s0304-3975(99)00206-6Bravenboer, M., Kalleberg, K. T., Vermaas, R., & Visser, E. (2008). Stratego/XT 0.17. A language and toolset for program transformation. Science of Computer Programming, 72(1-2), 52-70. doi:10.1016/j.scico.2007.11.003Bruni, R., & Meseguer, J. (2006). Semantic foundations for generalized rewrite theories. Theoretical Computer Science, 360(1-3), 386-414. doi:10.1016/j.tcs.2006.04.012M. Clavel, F. Durán, S. Eker, S. Escobar, P. Lincoln, N. Martí-Oliet, C.L. Talcott, Two decades of Maude, in: [86], 2015, pp. 232–254.Clavel, M., Durán, F., Eker, S., Lincoln, P., Martı́-Oliet, N., Meseguer, J., & Quesada, J. F. (2002). Maude: specification and programming in rewriting logic. Theoretical Computer Science, 285(2), 187-243. doi:10.1016/s0304-3975(01)00359-0Clavel, M., & Meseguer, J. (2002). Reflection in conditional rewriting logic. Theoretical Computer Science, 285(2), 245-288. doi:10.1016/s0304-3975(01)00360-7F. Durán, S. Eker, S. Escobar, N. Martí-Oliet, J. Meseguer, C.L. Talcott, Associative unification and symbolic reasoning modulo associativity in Maude, in: [121], 2018, pp. 98–114.Durán, F., Lucas, S., Marché, C., Meseguer, J., & Urbain, X. (2008). Proving operational termination of membership equational programs. Higher-Order and Symbolic Computation, 21(1-2), 59-88. doi:10.1007/s10990-008-9028-2F. Durán, J. Meseguer, An extensible module algebra for Maude, in: [77], 1998, pp. 174–195.Durán, F., & Meseguer, J. (2003). Structured theories and institutions. Theoretical Computer Science, 309(1-3), 357-380. doi:10.1016/s0304-3975(03)00312-8Durán, F., & Meseguer, J. (2007). Maude’s module algebra. Science of Computer Programming, 66(2), 125-153. doi:10.1016/j.scico.2006.07.002Durán, F., & Meseguer, J. (2012). On the Church-Rosser and coherence properties of conditional order-sorted rewrite theories. The Journal of Logic and Algebraic Programming, 81(7-8), 816-850. doi:10.1016/j.jlap.2011.12.004F. Durán, P.C. Ölveczky, A guide to extending Full Maude illustrated with the implementation of Real-Time Maude, in: [116], 2009, pp. 83–102.S. Escobar, Multi-paradigm programming in Maude, in: [121], 2018, pp. 26–44.Escobar, S., Meadows, C., Meseguer, J., & Santiago, S. (2014). State space reduction in the Maude-NRL Protocol Analyzer. Information and Computation, 238, 157-186. doi:10.1016/j.ic.2014.07.007Escobar, S., Sasse, R., & Meseguer, J. (2012). Folding variant narrowing and optimal variant termination. The Journal of Logic and Algebraic Programming, 81(7-8), 898-928. doi:10.1016/j.jlap.2012.01.002H. Garavel, M. Tabikh, I. Arrada, Benchmarking implementations of term rewriting and pattern matching in algebraic, functional, and object-oriented languages – the 4th rewrite engines competition, in: [121], 2018, pp. 1–25.Goguen, J. A., & Burstall, R. M. (1992). Institutions: abstract model theory for specification and programming. Journal of the ACM, 39(1), 95-146. doi:10.1145/147508.147524Goguen, J. A., & Meseguer, J. (1984). Equality, types, modules, and (why not?) generics for logic programming. The Journal of Logic Programming, 1(2), 179-210. doi:10.1016/0743-1066(84)90004-9Goguen, J. A., & Meseguer, J. (1992). Order-sorted algebra I: equational deduction for multiple inheritance, overloading, exceptions and partial operations. Theoretical Computer Science, 105(2), 217-273. doi:10.1016/0304-3975(92)90302-vR. Gutiérrez, J. Meseguer, Variant-based decidable satisfiability in initial algebras with predicates, in: [61], 2018, pp. 306–322.Gutiérrez, R., Meseguer, J., & Rocha, C. (2015). Order-sorted equality enrichments modulo axioms. Science of Computer Programming, 99, 235-261. doi:10.1016/j.scico.2014.07.003Horn, A. (1951). On sentences which are true of direct unions of algebras. Journal of Symbolic Logic, 16(1), 14-21. doi:10.2307/2268661Katelman, M., Keller, S., & Meseguer, J. (2012). Rewriting semantics of production rule sets. The Journal of Logic and Algebraic Programming, 81(7-8), 929-956. doi:10.1016/j.jlap.2012.06.002Kowalski, R. (1979). Algorithm = logic + control. Communications of the ACM, 22(7), 424-436. doi:10.1145/359131.359136Lucanu, D., Rusu, V., & Arusoaie, A. (2017). A generic framework for symbolic execution: A coinductive approach. Journal of Symbolic Computation, 80, 125-163. doi:10.1016/j.jsc.2016.07.012D. Lucanu, V. Rusu, A. Arusoaie, D. Nowak, Verifying reachability-logic properties on rewriting-logic specifications, in: [86], 2015, pp. 451–474.Lucas, S., & Meseguer, J. (2016). Normal forms and normal theories in conditional rewriting. Journal of Logical and Algebraic Methods in Programming, 85(1), 67-97. doi:10.1016/j.jlamp.2015.06.001N. Martí-Oliet, J. Meseguer, A. Verdejo, A rewriting semantics for Maude strategies, in: [116], 2009, pp. 227–247.Martí-Oliet, N., Palomino, M., & Verdejo, A. (2007). Strategies and simulations in a semantic framework. Journal of Algorithms, 62(3-4), 95-116. doi:10.1016/j.jalgor.2007.04.002Meseguer, J. (1992). Conditional rewriting logic as a unified model of concurrency. Theoretical Computer Science, 96(1), 73-155. doi:10.1016/0304-3975(92)90182-fMeseguer, J. (2012). Twenty years of rewriting logic. The Journal of Logic and Algebraic Programming, 81(7-8), 721-781. doi:10.1016/j.jlap.2012.06.003Meseguer, J. (2017). Strict coherence of conditional rewriting modulo axioms. Theoretical Computer Science, 672, 1-35. doi:10.1016/j.tcs.2016.12.026J. Meseguer, Generalized rewrite theories and coherence completion, in: [121], 2018, pp. 164–183.Meseguer, J. (2018). Variant-based satisfiability in initial algebras. Science of Computer Programming, 154, 3-41. doi:10.1016/j.scico.2017.09.001Meseguer, J., Goguen, J. A., & Smolka, G. (1989). Order-sorted unification. Journal of Symbolic Computation, 8(4), 383-413. doi:10.1016/s0747-7171(89)80036-7Meseguer, J., & Ölveczky, P. C. (2012). Formalization and correctness of the PALS architectural pattern for distributed real-time systems. Theoretical Computer Science, 451, 1-37. doi:10.1016/j.tcs.2012.05.040Meseguer, J., Palomino, M., & Martí-Oliet, N. (2008). Equational abstractions. Theoretical Computer Science, 403(2-3), 239-264. doi:10.1016/j.tcs.2008.04.040Meseguer, J., & Roşu, G. (2007). The rewriting logic semantics project. Theoretical Computer Science, 373(3), 213-237. doi:10.1016/j.tcs.2006.12.018Meseguer, J., & Roşu, G. (2013). The rewriting logic semantics project: A progress report. Information and Computation, 231, 38-69. doi:10.1016/j.ic.2013.08.004Meseguer, J., & Skeirik, S. (2017). Equational formulas and pattern operations in initial order-sorted algebras. Formal Aspects of Computing, 29(3), 423-452. doi:10.1007/s00165-017-0415-5Meseguer, J., & Thati, P. (2007). Symbolic reachability analysis using narrowing and its application to verification of cryptographic protocols. Higher-Order and Symbolic Computation, 20(1-2), 123-160. doi:10.1007/s10990-007-9000-6C. Olarte, E. Pimentel, C. Rocha, Proving structural properties of sequent systems in rewriting logic, in: [121], 2018, pp. 115–135.Ölveczky, P. C., & Meseguer, J. (2007). Semantics and pragmatics of Real-Time Maude. Higher-Order and Symbolic Computation, 20(1-2), 161-196. doi:10.1007/s10990-007-9001-5Ölveczky, P. C., & Thorvaldsen, S. (2009). Formal modeling, performance estimation, and model checking of wireless sensor network algorithms in Real-Time Maude. Theoretical Computer Science, 410(2-3), 254-280. doi:10.1016/j.tcs.2008.09.022Rocha, C., Meseguer, J., & Muñoz, C. (2017). Rewriting modulo SMT and open system analysis. Journal of Logical and Algebraic Methods in Programming, 86(1), 269-297. doi:10.1016/j.jlamp.2016.10.001Şerbănuţă, T. F., Roşu, G., & Meseguer, J. (2009). A rewriting logic approach to operational semantics. Information and Computation, 207(2), 305-340. doi:10.1016/j.ic.2008.03.026Skeirik, S., & Meseguer, J. (2018). Metalevel algorithms for variant satisfiability. Journal of Logical and Algebraic Methods in Programming, 96, 81-110. doi:10.1016/j.jlamp.2017.12.006S. Skeirik, A. Ştefănescu, J. Meseguer, A constructor-based reachability logic for rewrite theories, in: [61], 2018, pp. 201–217.Strachey, C. (2000). Higher-Order and Symbolic Computation, 13(1/2), 11-49. doi:10.1023/a:1010000313106A. Ştefănescu, S. Ciobâcă, R. Mereuta, B.M. Moore, T. Serbanuta, G. Roşu, All-path reachability logic, in: [36], 2014, pp. 425–440.Tushkanova, E., Giorgetti, A., Ringeissen, C., & Kouchnarenko, O. (2015). A rule-based system for automatic decidability and combinability. Science of Computer Programming, 99, 3-23. doi:10.1016/j.scico.2014.02.00

Modelling and analyzing adaptive self-assembling strategies with Maude

Building adaptive systems with predictable emergent behavior is a challenging task and it is becoming a critical need. The research community has accepted the challenge by introducing approaches of various nature: from software architectures, to programming paradigms, to analysis techniques. We recently proposed a conceptual framework for adaptation centered around the role of control data. In this paper we show that it can be naturally realized in a reflective logical language like Maude by using the Reflective Russian Dolls model. Moreover, we exploit this model to specify and analyse a prominent example of adaptive system: robot swarms equipped with obstacle-avoidance self-assembly strategies. The analysis exploits the statistical model checker PVesta

Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems

Desde los orígenes del hardware y el software hasta la época actual, la complejidad de los sistemas de cálculo ha supuesto un problema al cual informáticos, ingenieros y programadores han tenido que enfrentarse. Como resultado de este esfuerzo han surgido y madurado importantes áreas de investigación. En esta disertación abordamos algunas de las líneas de investigación actuales relacionada con el análisis y la verificación de sistemas de computación complejos utilizando métodos formales y lenguajes de dominio específico. En esta tesis nos centramos en los sistemas distribuidos, con un especial interés por los sistemas Web y los sistemas biológicos. La primera parte de la tesis está dedicada a aspectos de seguridad y técnicas relacionadas, concretamente la certificación del software. En primer lugar estudiamos sistemas de control de acceso a recursos y proponemos un lenguaje para especificar políticas de control de acceso que están fuertemente asociadas a bases de conocimiento y que proporcionan una descripción sensible a la semántica de los recursos o elementos a los que se accede. También hemos desarrollado un marco novedoso de trabajo para la Code-Carrying Theory, una metodología para la certificación del software cuyo objetivo es asegurar el envío seguro de código en un entorno distribuido. Nuestro marco de trabajo está basado en un sistema de transformación de teorías de reescritura mediante operaciones de plegado/desplegado. La segunda parte de esta tesis se concentra en el análisis y la verificación de sistemas Web y sistemas biológicos. Proponemos un lenguaje para el filtrado de información que permite la recuperación de informaciones en grandes almacenes de datos. Dicho lenguaje utiliza información semántica obtenida a partir de ontologías remotas para re nar el proceso de filtrado. También estudiamos métodos de validación para comprobar la consistencia de contenidos web con respecto a propiedades sintácticas y semánticas. Otra de nuestras contribuciones es la propuesta de un lenguaje que permite definir y comprobar automáticamente restricciones semánticas y sintácticas en el contenido estático de un sistema Web. Finalmente, también consideramos los sistemas biológicos y nos centramos en un formalismo basado en lógica de reescritura para el modelado y el análisis de aspectos cuantitativos de los procesos biológicos. Para evaluar la efectividad de todas las metodologías propuestas, hemos prestado especial atención al desarrollo de prototipos que se han implementado utilizando lenguajes basados en reglas.Baggi ., M. (2010). Rule-based Methodologies for the Specification and Analysis of Complex Computing Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/8964Palanci

The design and implementation of a relational programming system.

The declarative class of computer languages consists mainly of two paradigms - the logic and the functional. Much research has been devoted in recent years to the integration of the two with the aim of securing the advantages of both without retaining their disadvantages. To date this research has, arguably, been less fruitful than initially hoped. A large number of composite functional/logical languages have been proposed but have generally been marred by the lack of a firm, cohesive, mathematical basis. More recently new declarative paradigms, equational and constraint languages, have been advocated. These however do not fully encompass those features we perceive as being central to functional and logic languages. The crucial functional features are higher-order definitions, static polymorphic typing, applicative expressions and laziness. The crucial logic features are ability to reason about both functional and non-functional relationships and to handle computations involving search. This thesis advocates a new declarative paradigm which lies midway between functional and logic languages - the so-called relational paradigm. In a relationallanguage program and data alike are denoted by relations. All expressions are relations constructed from simpler expressions using operators which form a relational algebra. The impetus for use of relations in a declarative language comes from observations concerning their connection to functional and logic programming. Relations are mathematically more general than functions modelling non-functional as well as functional relationships. They also form the basis of many logic languages, for example, Prolog. This thesis proposes a new relational language based entirely on binary relations, named Drusilla. We demonstrate the functional and logic aspects of Drusilla. It retains the higher-order objects and polymorphism found in modern functional languages but handles non-determinism and models relationships between objects in the manner of a logic language with notion of algorithm being composed of logic and control elements. Different programming styles - functional, logic and relational- are illustrated. However, such expressive power does not come for free; it has associated with it a high cost of implementation. Two main techniques are used in the necessarily complex language interpreter. A type inference system checks programs to ensure they are meaningful and simultaneously performs automatic representation selection for relations. A symbolic manipulation system transforms programs to improve. efficiency of expressions and to increase the number of possible representations for relations while preserving program meaning

The design and implementation of a multiparadigm programming language.

by Chi-keung Luk.Thesis (M.Phil.)--Chinese University of Hong Kong, 1993.Includes bibliographical references (leaves 169-174).Preface --- p.xiChapter 1 --- Introduction --- p.1Chapter 1.1 --- Programming Languages --- p.2Chapter 1.2 --- Programming Paradigms --- p.2Chapter 1.2.1 --- What is a programming paradigm --- p.2Chapter 1.2.2 --- Which came first? Languages or paradigms? --- p.2Chapter 1.2.3 --- Overview of some paradigms --- p.4Chapter 1.2.4 --- A spectrum of paradigms --- p.6Chapter 1.2.5 --- Mulitparadigm systems --- p.7Chapter 1.3 --- The Objectives of this research --- p.8Chapter 2 --- "Studies of the object-oriented, the logic and the functional paradigms" --- p.10Chapter 2.1 --- The Object-Oriented Paradigm --- p.10Chapter 2.1.1 --- Basic components --- p.10Chapter 2.1.2 --- Motivations --- p.11Chapter 2.1.3 --- Some related issues --- p.12Chapter 2.1.4 --- Computational models for object-oriented programming --- p.16Chapter 2.2 --- The Functional Paradigm --- p.18Chapter 2.2.1 --- Basic concepts --- p.18Chapter 2.2.2 --- Lambda calculus --- p.20Chapter 2.2.3 --- The characteristics of functional programs --- p.21Chapter 2.2.4 --- Practicality of functional programming --- p.25Chapter 2.3 --- The Logic Paradigm --- p.28Chapter 2.3.1 --- Relations --- p.28Chapter 2.3.2 --- Logic programs --- p.29Chapter 2.3.3 --- The opportunity for parallelism --- p.30Chapter 2.4 --- Summary --- p.31Chapter 3 --- A survey of some existing multiparadigm languages --- p.32Chapter 3.1 --- Logic + Object-Oriented --- p.33Chapter 3.1.1 --- LogiC++ --- p.33Chapter 3.1.2 --- Intermission --- p.34Chapter 3.1.3 --- Object-Oriented Programming in Prolog (OOPP) --- p.36Chapter 3.1.4 --- Communication Prolog Unit (CPU) --- p.37Chapter 3.1.5 --- DLP --- p.37Chapter 3.1.6 --- Representing Objects in a Logic Programming Language with Scoping Constructs (OLPSC) --- p.39Chapter 3.1.7 --- KSL/Logic --- p.40Chapter 3.1.8 --- Orient84/K --- p.41Chapter 3.1.9 --- Vulcan --- p.42Chapter 3.1.10 --- The Bridge approach --- p.43Chapter 3.1.11 --- Discussion --- p.44Chapter 3.2 --- Functional + Object-Oriented --- p.46Chapter 3.2.1 --- PROOF --- p.46Chapter 3.2.2 --- A Functional Language with Classes (FLC) --- p.47Chapter 3.2.3 --- Common Lisp Object System (CLOS) --- p.49Chapter 3.2.4 --- FOOPS --- p.50Chapter 3.2.5 --- Discussion --- p.51Chapter 3.3 --- Logic + Functional --- p.52Chapter 3.3.1 --- HOPE --- p.52Chapter 3.3.2 --- FUNLOG --- p.54Chapter 3.3.3 --- F* --- p.55Chapter 3.3.4 --- LEAF --- p.56Chapter 3.3.5 --- Applog --- p.57Chapter 3.3.6 --- Discussion --- p.58Chapter 3.4 --- Logic + Functional + Object-Oriented --- p.61Chapter 3.4.1 --- Paradise --- p.61Chapter 3.4.2 --- LIFE --- p.62Chapter 3.4.3 --- UNIFORM --- p.63Chapter 3.4.4 --- G --- p.64Chapter 3.4.5 --- FOOPlog --- p.66Chapter 3.4.6 --- Logic and Objects (L&O) --- p.66Chapter 3.4.7 --- Discussion --- p.67Chapter 4 --- The design of a multiparadigm language I --- p.70Chapter 4.1 --- An Object-Oriented Framework --- p.71Chapter 4.1.1 --- A hierarchy of classes --- p.71Chapter 4.1.2 --- Program structure --- p.71Chapter 4.1.3 --- Parametric classes --- p.72Chapter 4.1.4 --- Inheritance --- p.73Chapter 4.1.5 --- The meanings of classes and methods --- p.75Chapter 4.1.6 --- Objects and messages --- p.75Chapter 4.2 --- The logic Subclasses --- p.76Chapter 4.2.1 --- Syntax --- p.76Chapter 4.2.2 --- Distributed inference --- p.76Chapter 4.2.3 --- Adding functions and expressions to logic programs --- p.77Chapter 4.2.4 --- State modelling --- p.79Chapter 4.3 --- The functional Subclasses --- p.80Chapter 4.3.1 --- The syntax of functions --- p.80Chapter 4.3.2 --- Abstract data types --- p.81Chapter 4.3.3 --- Augmented list comprehensions --- p.82Chapter 4.4 --- The Semantic Foundation of I Programs --- p.84Chapter 4.4.1 --- T1* : Transform functions into Horn clauses --- p.84Chapter 4.4.2 --- T2*: Transform object-oriented features into pure logic --- p.85Chapter 4.5 --- Exploiting Parallelism in I Programs --- p.89Chapter 4.5.1 --- Inter-object parallelism --- p.89Chapter 4.5.2 --- Intra-object parallelism --- p.92Chapter 4.6 --- Discussion --- p.96Chapter 5 --- An implementation of a prototype of I --- p.99Chapter 5.1 --- System Overview --- p.99Chapter 5.2 --- I-to-Prolog Translation --- p.101Chapter 5.2.1 --- Pass 1 - lexical and syntax analysis --- p.101Chapter 5.2.2 --- Pass 2 - Class Table Construction and Semantic Checking --- p.101Chapter 5.2.3 --- Pass 3 - Determination of Multiple Inheritance Precedence --- p.105Chapter 5.2.4 --- Pass 4 - Translation of the directive part --- p.110Chapter 5.2.5 --- Pass 5 - Creation of Prolog source code for an I object --- p.110Chapter 5.2.6 --- Using expressions in logic methods --- p.112Chapter 5.3 --- I-to-LML Translation --- p.114Chapter 5.4 --- The Run-time Handler --- p.117Chapter 5.4.1 --- Object Management --- p.118Chapter 5.4.2 --- Process Management and Message Passing --- p.121Chapter 6 --- Some applications written in I --- p.125Chapter 6.1 --- Modeling of a State Space Search --- p.125Chapter 6.2 --- A Solution to the N-queen Problem --- p.129Chapter 6.3 --- Object-Oriented Modeling of a Database --- p.131Chapter 6.4 --- A Simple Expert System --- p.133Chapter 6.5 --- Summary --- p.138Chapter 7 --- Conclusion and future work --- p.139Chapter 7.1 --- Conclusion --- p.139Chapter 7.2 --- Future Work --- p.141Chapter A --- Language manual --- p.146Chapter A.1 --- Introduction --- p.146Chapter A.2 --- Syntax --- p.146Chapter A.2.1 --- The lexical specification --- p.146Chapter A.2.2 --- The syntax specification --- p.149Chapter A3 --- Classes --- p.152Chapter A.4 --- Object Creation and Method Invocation --- p.153Chapter A.5 --- The logic Subclasses --- p.155Chapter A.6 --- The functional Subclasses --- p.156Chapter A.7 --- Types --- p.158Chapter A.8 --- Mutable States --- p.158Chapter B --- User's guide --- p.160Chapter B.1 --- System Calls --- p.160Chapter B.2 --- Configuration Parameters --- p.162Chapter B.3 --- Errors --- p.163Chapter B.4 --- Implementation Limits --- p.164Chapter B.5 --- How to install the system --- p.164Chapter B.6 --- How to use the system --- p.164Chapter B.7 --- How to recompile the system --- p.166Chapter B.8 --- Directory arrangement --- p.167Chapter C --- List of publications --- p.168Bibliography --- p.16