Revisiting visitors for modular extension of executable DSMLs

Executable Domain-Specific Modeling Languages (xDSMLs) are typically defined by metamodels that specify their abstract syntax, and model interpreters or compilers that define their execution semantics. To face the proliferation of xDSMLs in many domains, it is important to provide language engineering facilities for opportunistic reuse, extension, and customization of existing xDSMLs to ease the definition of new ones. Current approaches to language reuse either require to anticipate reuse, make use of advanced features that are not widely available in programming languages, or are not directly applicable to metamodel-based xDSMLs. In this paper, we propose a new language implementation pattern, named Revisitor, that enables independent extensibility of the syntax and semantics of metamodel-based xDSMLs with incremental compilation and without anticipation. We seamlessly implement our approach alongside the compilation chain of the Eclipse Modeling Framework, thereby demonstrating that it is directly and broadly applicable in various modeling environments. We show how it can be employed to incrementally extend both the syntax and semantics of the fUML language without requiring anticipation or re-compilation of existing code, and with acceptable performance penalty compared to classical handmade visitors

Adaptation of Service-Based Systems

The advances in modern technology development and future technology changes dictate new challenges and requirements to the engineering and provision of services and service-based systems (SBS). These services and systems should become drastically more flexible; they should be able to operate and evolve in highly dynamic environments and to adequately react to various changes in these environments. In these settings, adaptability becomes a key feature of services as it provides a way for an application to continuously change itself in order to satisfy new contextual requirements. Events and conditions triggering application adaptation include: changes in the infrastructural layer of the application due to quality of service changes; changes of the (hybrid) application context and location; changes of the user types, preferences, and constraints that require application customization and personalization as a means to adapt the application behavior to a particular user; changes in the functionalities provided by the component services that requires modifying the way in which services are composed and coordinated; and changes in the way the service is being used and managed by its consumers, which in turn leads to changes in the application requirements

Recherche et traitement de l'information dans la résolution de différents types de problèmes par les enfants

Audigier M. N., Cauzinille-Marmèche Évelyne, Mathieu Jacques, Richard J. F., Sebillotte S., Weil-Barais A. Recherche et traitement de l'information dans la résolution de différents types de problèmes par les enfants. In: Bulletin de psychologie, tome 32 n°340, 1979. L'intelligence. pp. 721-735