The State of the Art in Language Workbenches. Conclusions from the Language Workbench Challenge

Language workbenches are tools that provide high-level mechanisms for the implementation of (domain-specific) languages. Language workbenches are an active area of research that also receives many contributions from industry. To compare and discuss existing language workbenches, the annual Language Workbench Challenge was launched in 2011. Each year, participants are challenged to realize a given domain-specific language with their workbenches as a basis for discussion and comparison. In this paper, we describe the state of the art of language workbenches as observed in the previous editions of the Language Workbench Challenge. In particular, we capture the design space of language workbenches in a feature model and show where in this design space the participants of the 2013 Language Workbench Challenge reside. We compare these workbenches based on a DSL for questionnaires that was realized in all workbenches

Using Indexed and Synchronous Events to Model and Validate Cyber-Physical Systems

Timed Transition Models (TTMs) are event-based descriptions for modelling, specifying, and verifying discrete real-time systems. An event can be spontaneous, fair, or timed with specified bounds. TTMs have a textual syntax, an operational semantics, and an automated tool supporting linear-time temporal logic. We extend TTMs and its tool with two novel modelling features for writing high-level specifications: indexed events and synchronous events. Indexed events allow for concise description of behaviour common to a set of actors. The indexing construct allows us to select a specific actor and to specify a temporal property for that actor. We use indexed events to validate the requirements of a train control system. Synchronous events allow developers to decompose simultaneous state updates into actions of separate events. To specify the intended data flow among synchronized actions, we use primed variables to reference the post-state (i.e., one resulted from taking the synchronized actions). The TTM tool automatically infers the data flow from synchronous events, and reports errors on inconsistencies due to circular data flow. We use synchronous events to validate part of the requirements of a nuclear shutdown system. In both case studies, we show how the new notation facilitates the formal validation of system requirements, and use the TTM tool to verify safety, liveness, and real-time properties.Comment: In Proceedings ESSS 2015, arXiv:1506.0325

Specifying Software Languages: Grammars, Projectional Editors, and Unconventional Approaches

We discuss several approaches for defining software languages, together with Integrated Development Environments for them. Theoretical foundation is grammar-based models: they can be used where proven correctness of specifications is required. From a practical point of view, we discuss how language specification can be made more accessible by focusing on language workbenches and projectional editing, and discuss how it can be formalized. We also give a brief overview of unconventional ideas to language definition, and outline three open problems connected to the approaches we discuss

Modelling of mathematical programs: An analysis of strategy and an outline description of a computer assisted system

The salient components of the mathematical programming modeling activity are first analysed. Earlier generation systems such as program generators and procedural (modelling) languages are briefly discussed. A proposal for a computer assisted modelling scheme is then put forward. The proposed system contrasts with the earlier approaches in that no computer programming expertise is required on the part of the modeller. A mathematical programming model is usually constructed by progressive definition of dimensions, data tables, model variables, model constraints and the matrix coefficients which connect the last two entities. The philosophy and design of the experimental system supports this approach to model description. This aspect is illustrated by a few examples. The introduction of computer assistance in structuring of the data and the resulting model is novel and is in line with recent developments in friendly and flexible user interface

Pristup integraciji tehničkih prostora zasnovan na preslikavanjima iinženjerstvu vođenom modelima

In order to automate development of integration adapters in industrial settings, a model-driven approach to adapter specification is devised. In this approach, a domain-specific modeling language is created to allow specification of mappings between integrated technical spaces. Also proposed is the mapping automation engine that comprises reuse and alignment algorithms. Based on mapping specifications, executable adapters are automatically generated and executed. Results of approach evaluations indicate that it is possible to use a model-driven approach to successfully integrate technical spaces and increase the automation by reusing domainspecific mappings from previously created adapters.За потребе повећања степена аутоматизације развоја адаптера за интеграцију у индустријском окружењу, осмишљен је моделом вођен приступ развоју адаптера. У оквиру овог приступа развијен је наменски језик за спецификацију пресликавања између техничких простора који су предмет интеграције. Приступ обухвата и алгоритме за поравнање и поновно искориштење претходно креираних пресликавања са циљем аутоматизације процеса спецификације. На основу креираних пресликавања, могуће je аутоматски генерисати извршиви код адаптера. У испитивањима приступа, показано је да је могуће успешно применити моделом вођен приступ у интеграцији техничких простора као и да је могуће успешно повећати степен аутоматизације поновним искоришћењем претходно креираних пресликавања.Za potrebe povećanja stepena automatizacije razvoja adaptera za integraciju u industrijskom okruženju, osmišljen je modelom vođen pristup razvoju adaptera. U okviru ovog pristupa razvijen je namenski jezik za specifikaciju preslikavanja između tehničkih prostora koji su predmet integracije. Pristup obuhvata i algoritme za poravnanje i ponovno iskorištenje prethodno kreiranih preslikavanja sa ciljem automatizacije procesa specifikacije. Na osnovu kreiranih preslikavanja, moguće je automatski generisati izvršivi kod adaptera. U ispitivanjima pristupa, pokazano je da je moguće uspešno primeniti modelom vođen pristup u integraciji tehničkih prostora kao i da je moguće uspešno povećati stepen automatizacije ponovnim iskorišćenjem prethodno kreiranih preslikavanja

ICD Management (ICDM) tool for embedded systems on aircrafts

International audienceIn the scope of on-board systems development and integration for aircrafts, ICDs (Interface Control Document/Description) are fundamental sources of information at same level that the functional requirements. ICD description must include feasible (bus capacity not exceeded, processing load under specific limits) and accurate (data precision, data retransmission rate, data consistency) inter-connectivity mechanisms, to support the application requirements needs, as well as the information must be easy to update and to maintain.On the other hand, DOORS (IBM) is a tool specialized on requirements management. It faces with aspects as traceability, version control, security (access control), changes control, data persistency and accessibility. DOORS is widely used and it is recognized as a reference tool in the scope of aeronautic developments.Nevertheless, ICD information usually is not managed with DOORS. The reason can be found in the specificities of the nature of ICD information, which suggests other approaches more suitable than DOORS.The alternative approaches are very diverse but most of them focus on handling information typified according to specific meta-models for ICD: databases, customized spreadsheets, and tabular descriptions. But whatever is the solution, it must address also, by its own means, the features of ICD derived of its “requirement nature”.This paper presents a solution based on the integration of DOORS with a user front-end developed with Model Driven Architecture (MDA) and Open Source technologies. It is intended to provide means to manage ICD data in a robust way (guaranteeing the correctness -syntactic, completeness, non ambiguity- of data, changes, versions, dependencies, ...) and additionally, to provide mechanisms to focus the effort on the data transformation rather than on the manual elaboration of derived artefacts

Validating multiple variants of an automotive light system with electrum

All resources relevant for the ELS case study are available at: https://github.com/haslab/Electrum2/wiki/ELS.This paper reports on the development and validation of a formal model for an automotive adaptive exterior lights system (ELS) with multiple variants in Electrum, a lightweight formal specification language that extends Alloy with mutable relations and temporal logic. We explore different strategies to address variability, one in pure Electrum and another through an annotative language extension. We then show how Electrum and its Analyzer can be used to validate systems of this nature, namely by checking that the reference scenarios are admissible, and to automatically verify whether the established requirements hold. A prototype was developed to translate the provided validation sequences into Electrum and back to further automate the validation process. The resulting ELS model was validated against the provided validation sequences and verified for most of requirements for all variants.The authors would like to thank Frank Houdek for helping clarifying the requirements. This work is financed by National Funds through the Portuguese funding agency, FCT – Fundação para a Ciência e a Tecnologia, within project UIDB/50014/2020. The third author was financed by the ERDF – European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation – COMPETE 2020 Programme and by National Funds through the FCT, within project POCI-01-0145-FEDER-016826

Ada style guide (version 1.1)

Ada is a programming language of considerable expressive power. The Ada Language Reference Manual provides a thorough definition of the language. However, it does not offer sufficient guidance on the appropriate use of Ada's powerful features. For this reason, the Goddard Space Flight Center Ada User's Group has produced this style guide which addresses such program style issues. The guide covers three areas of Ada program style: the structural decomposition of a program; the coding and the use of specific Ada features; and the textural formatting of a program