Die C# Schnittstelle der Referenzattributgrammatik-gesteuerten Graphersetzungsbibliothek RACR: Übersicht, Anwendung und Implementierung: Entwicklerhandbuch

Dieser Bericht präsentiert RACR-NET, eine Schnittstelle der Referenzattributgrammatik-gesteuerten Graphersetzungsbibliothek RACR für C#. RACR-NET ermöglicht die Nutzung der deklarativen, dynamischen Sprachspezifikations-, Instanziierungs- und Auswertungsmeachanismen der RACR Scheme-Bibliothek in der objektorientierten Programmierung. Dies umfasst insbesondere die automatische inkrementelle Auswertung attributbasierter semantischer Analysen und somit das automatische Cachen parametrisierter Funktionsmethoden. Graphersetzungen entsprechen hierbei Zustandsänderungen von Objektinstanzen und der Invalidierung abgeleiteter Berechnungen. Schwerpunkt dieses Berichts ist die objektorientierte Programmierschnittstelle von RACR-NET, dessen praktische Anwendung und Implementierung. Der Bericht ist ein Referenzhandbuch für RACR-NET Anwender und Entwickler.:1. Einleitung 1.1. Aufgabenstellung 1.2. Struktur der Arbeit 2. Konzeptionelle und technische Voraussetzungen 2.1. Überblick der RAG-gesteuerten Graphersetzung 2.2. Scheme 2.3. Die RACR Scheme-Bibliothek 2.4. Das .NET-Framework und die Common Language Infrastructure 2.5. IronScheme 3. RACR-NET Implementierung: Prozedurale Schnittstelle 3.1. Scheme in C# 3.2. RACR in C# 3.3. Anforderungsanalyse 3.4. Implementierung der prozeduralen Schnittstelle 4. RACR-NET Implementierung: Objektorientierte Schnittstelle 4.1. Überblick über die objektorientierte Schnittstelle 4.2. Anwendungsbeispiel 4.3. Herausforderungen bei der Implementierung 4.4. Implementierung 5. Evaluation 5.1. Testen der Schnittstelle 5.2. Performance-Messungen und -Vergleiche 6. Zusammenfassung und Ausblick 6.1. Eine objektorientierte Bibliothek für RAG-gesteuerte Graphersetzung 6.2. Zukünftige Arbeiten A. Literaturverzeichnis B. MIT Lizen

Towards Attribute Grammars for Metamodel Semantics

Of key importance for metamodelling are appropriate modelling formalisms. Most metamodelling languages permit the development of metamodels that specify tree-structured models enriched with semantics like constraints, references and operations, which extend the models to graphs. However, often the semantics of these semantic constructs is not part of the metamodel, i.e., it is unspeci ed. Therefore, we propose to reuse well-known compiler construction techniques to specify metamodel semantics. To be more precise, we present the application of reference attribute grammars (RAGs) for metamodel semantics and analyse commonalities and differences. Our focus is to pave the way for such a combination, by exemplifying why and how the metamodelling and attribute grammar (AG) world can be combined and by investigating a concrete example - the combination of the Eclipse Modelling Framework (EMF) and JastAdd, an AG evaluator generator

IEEE/NASA Workshop on Leveraging Applications of Formal Methods, Verification, and Validation

This volume contains the Preliminary Proceedings of the 2005 IEEE ISoLA Workshop on Leveraging Applications of Formal Methods, Verification, and Validation, with a special track on the theme of Formal Methods in Human and Robotic Space Exploration. The workshop was held on 23-24 September 2005 at the Loyola College Graduate Center, Columbia, MD, USA. The idea behind the Workshop arose from the experience and feedback of ISoLA 2004, the 1st International Symposium on Leveraging Applications of Formal Methods held in Paphos (Cyprus) last October-November. ISoLA 2004 served the need of providing a forum for developers, users, and researchers to discuss issues related to the adoption and use of rigorous tools and methods for the specification, analysis, verification, certification, construction, test, and maintenance of systems from the point of view of their different application domains

Well-Formed and Scalable Invasive Software Composition

Software components provide essential means to structure and organize software effectively. However, frequently, required component abstractions are not available in a programming language or system, or are not adequately combinable with each other. Invasive software composition (ISC) is a general approach to software composition that unifies component-like abstractions such as templates, aspects and macros. ISC is based on fragment composition, and composes programs and other software artifacts at the level of syntax trees. Therefore, a unifying fragment component model is related to the context-free grammar of a language to identify extension and variation points in syntax trees as well as valid component types. By doing so, fragment components can be composed by transformations at respective extension and variation points so that always valid composition results regarding the underlying context-free grammar are yielded. However, given a language’s context-free grammar, the composition result may still be incorrect. Context-sensitive constraints such as type constraints may be violated so that the program cannot be compiled and/or interpreted correctly. While a compiler can detect such errors after composition, it is difficult to relate them back to the original transformation step in the composition system, especially in the case of complex compositions with several hundreds of such steps. To tackle this problem, this thesis proposes well-formed ISC—an extension to ISC that uses reference attribute grammars (RAGs) to specify fragment component models and fragment contracts to guard compositions with context-sensitive constraints. Additionally, well-formed ISC provides composition strategies as a means to configure composition algorithms and handle interferences between composition steps. Developing ISC systems for complex languages such as programming languages is a complex undertaking. Composition-system developers need to supply or develop adequate language and parser specifications that can be processed by an ISC composition engine. Moreover, the specifications may need to be extended with rules for the intended composition abstractions. Current approaches to ISC require complete grammars to be able to compose fragments in the respective languages. Hence, the specifications need to be developed exhaustively before any component model can be supplied. To tackle this problem, this thesis introduces scalable ISC—a variant of ISC that uses island component models as a means to define component models for partially specified languages while still the whole language is supported. Additionally, a scalable workflow for agile composition-system development is proposed which supports a development of ISC systems in small increments using modular extensions. All theoretical concepts introduced in this thesis are implemented in the Skeletons and Application Templates framework SkAT. It supports “classic”, well-formed and scalable ISC by leveraging RAGs as its main specification and implementation language. Moreover, several composition systems based on SkAT are discussed, e.g., a well-formed composition system for Java and a C preprocessor-like macro language. In turn, those composition systems are used as composers in several example applications such as a library of parallel algorithmic skeletons

Herramientas educativas para facilitar la adopción de la ingeniería de lenguajes software entre los desarrolladores informáticos

Históricamente, la materia de construcción de compiladores y procesadores de lenguaje es considerada por los estudiantes de ingeniería en informática como una materia difícil. Esto es debido, por una parte, a la naturaleza formal de las herramientas de especificación y diseño utilizadas, y, por otra, a la aplicación adecuada de diferentes técnicas sistemáticas de desarrollo para obtener los procesadores finales a partir de sus especificaciones. En esta tesis se aborda esta problemática en el caso particular de las gramáticas de atributos como formalismo básico de especificación. La tesis aborda, primeramente la concepción de una estrategia para facilitar la comprensión de los aspectos básicos de las especificaciones basadas en gramáticas de atributos, así como el soporte software de dicha estrategia. La estrategia propone un enfoque dirigido por problemas, en los que el alumno debe emular el proceso de evaluación semántica sobre distintos supuestos de procesamiento de frases de acuerdo con gramáticas de atributos. Para soportar dicha estrategia, se ha desarrollado un sistema denominado Evaluators, que, tomando como entrada baterías de ejercicios sobre evaluación semántica, produce automáticamente simuladores interactivos que los estudiantes pueden utilizar para resolver dichos ejercicios. El sistema proporciona, así mismo, una herramienta de autoría, que puede ser utilizada por los docentes para proporcionar los ejercicios, así como una herramienta de análisis, que permite trazar el comportamiento de los estudiantes durante la resolución de los mismos en los simuladores generados. Respecto a dichos simuladores, la herramienta es capaz de generar simulaciones de dos tipos: simuladores basados en juegos serios, y simulaciones interactivas basadas en las representaciones abstractas convencionales utilizadas en la materia. La tesis presenta, así mismo, diversos resultados de evaluación de la herramienta, tanto con estudiantes como con docentes, que evidencian la utilidad práctica de la misma. Por último, la tesis abstrae también el modelo de proceso utilizado en la construcción de la misma..