BSML-mbeddr: Integrating Semantically Congurable State-Machine Models in a C Programming Environment

In model-driven engineering, developers express their solutions in domain-specific modelling languages (DSLs) that support domain-specific abstractions. Big-Step Modelling Languages (BSML) is a family of extended state-machine DSLs for creating executable models that have a complex execution semantics. In this paper, we present BSML-mbeddr, which imbeds a large subset of BSML within the mbeddr C programming environment, thereby extending mbeddr with language constructs for extended, semantically configurable state-machines. We also report on three case studies that exercise the expressiveness of BSML-mbeddr, assess the integrability of BSML-mbeddr into mbeddr, and demonstrate the need to provide support for state-machine models with different execution semantics.NSERC Discovery Grant, 155243-12 || Ontario Research Fund, RE05-04

Type theory as a framework for modelling and programming

In the context provided by the proceedings of the UVMP track of ISoLA 2016, we propose Type Theory as a suitable framework for both modelling and programming. We show that it fits most of the requirements put forward on such frameworks by Broy et al. and discuss some of the objections that can be raised against it

Integrating Semantically Configurable State-machine Models in a C Programming Environment

Model-driven engineering is a popular software-development methodology, which requires suitable domain-specific modelling languages (DSLs) to create models. A DSL requires flexible semantics depending on the domain knowledge. Among DSLs, Big-Step Modelling Languages (BSML) is a family of state-machine modelling languages that vary semantically. In BSML, a model can respond to an environmental input with a big-step which comprises a sequence of small-steps, each of which represents the execution of a set of transitions. The semantics of BSMLs are decomposed into mostly orthogonal semantic aspects with a wide range of semantic options. With configurable semantics, the modeller is able to choose the proper option for each semantic aspect, thus to fulfil their per domain/model semantic requirements. In this thesis we present BSML-mbeddr, a state-machine modelling language with hierarchical states, concurrent regions and configurable semantics, which has implemented a large subset of BSML within the mbeddr C programming language environment. mbeddr is a DSL workbench which provides a tool suite that supports the incremental construction of modular DSLs on top of C, together with a set of predefined DSLs. By implementing on mbeddr, BSML-mbeddr is integrated into mbeddr-C that supports programs made with heterogeneous languages, including a combination of programming language and modelling language

DASH: Declarative Modelling with Control State Hierarchy (Preliminary Version)

We present a new language, called DASH, for describing formal behavioural models. DASH combines common modelling constructs to describe abstractly both data and control in an integrated manner. DASH uses the Alloy language for describing data and its operations declaratively, and adds syntax for labelled control state hierarchy common in Statecharts descriptions of transition systems. In addition, DASH accommodates multiple factoring paradigms for modelling (control states, events, and conditions) and includes syntactic sugar (e.g., transition comprehension, transition templates) to write models that are concise and easy to understand. We describe the formal semantics of DASH, which carefully mix the usual semantic understanding of control state hierarchy with the declarative perspective, for creating abstract models early in system development. We implement these semantics in a translator from DASH to Alloy taking advantage of Alloy language features. We demonstrate DASH, our tool, and model checking analysis in the Alloy Analyzer using several case studies. The key novel insight of our work is in combining seamlessly common data and control modelling paradigms in a way that will be intuitive for those used to either paradigm, and enabling automatic analysis of the integrated model

Assessing composition in modeling approaches

Modeling approaches are based on various paradigms, e.g., aspect-oriented, feature-oriented, object-oriented, and logic-based. Modeling approaches may cover requirements models to low-level design models, are developed for various purposes, use various means of composition, and thus are difficult to compare. However, such comparisons are critical to help practitioners know under which conditions approaches are most applicable, and how they might be successfully generalized and combined to achieve end-to-end methods. This paper reports on work done at the 2nd International Comparing Modeling Approaches (CMA) workshop towards the goal of identifying potential comprehensive modeling methodologies with a particular emphasis on composition: (i) an improved set of comparison criteria; (ii) 19 assessments of modeling approaches based on the comparison criteria and a common, focused case study

On the Syntactic, Semantic, and Pragmatic Quality of Students’ Conceptual Models

Visual notations and conceptual models, such as ER diagrams or UML diagrams aid in aligning stakeholder needs, defining and prioritizing processes and goals for the system under development, serve as a reference for requirements elicitation, negotiation, and enable validation as well as verification of artifacts. With such a ubiquitous presence and paramount importance, conceptual models have therefore been introduced in software engineering curricula far and wide. However, it is exceedingly difficult to teach and learn conceptual modeling. Not only does it require educators to instruct notation and syntax of the visual language, but also semantic intricacies. Similarly, students struggle with what differentiates a “good” conceptual model from an inadequate one, how to use conceptual models of different types in conjunction with one another in a meaningful way, or simply how to avoid ambiguity and vagueness. In this paper, we discuss the syntactic, semantic, and pragmatic quality of conceptual models in four courses from an undergraduate software engineering program. It is not our aim to present empirically rigorous results, but to contribute to the body of knowledge on the quality of typical novices’ conceptual models. We seek to foster discussion in the community and present observations and results for comparison

Heavy meta: model-driven domain-specific generation of generative domain-specific modeling tools

Software is so prevalent in all areas of life that one could expect we have come up with more simple and intuitive ways for its creation by now. However, software development is still too complicated to easily and efficiently cope with individual demands, customizations, and changes. Model-based approaches promise improvements through a more comprehensible layer of abstraction, but they are rarely fully embraced in practice. They are perceived as being overly complex, imposing additional work, and lacking the flexibility required in the real world. This thesis presents a novel approach to model-driven software engineering that focuses on simplicity through highly specialized tools. Domain experts are provided with development tools tailored to their individual needs, where they can easily specify the intent of the software using their known terms and concepts. This domain specificity (D) is a powerful mechanism to boil down the effort of defining a system to relevant aspects only. Many concepts are set upfront, which imposes a huge potential for automated generation. However, the full potential of domain-specific models can only unfold, if they are used as primary artifacts of development. The presented approach thus combines domain specificity with full generation (F) to achieve an overall pushbutton generation that does not require any round-trip engineering. Furthermore, service orientation (S) introduces a ‘just use’ philosophy of including arbitrarily complex functionality without needing to know their implementation, which also restores flexibility potentially sacrificed by the domain focus. The unique combination of these three DFS properties facilitates a focused, efficient, and flexible simplicity-driven way of software development. Key to the approach is a holistic solution that in particular also covers the simplicity-driven development of the required highly specialized DFS tools, as nothing would be gained if the costs of developing such tools outweighed the resulting benefits. This simplicity is achieved by applying the very same DFS concepts to the domain of tool development itself: DFS modeling tools are fully generated from models and services specialized to the (meta) domain of modeling tools. The presented Cinco meta tooling suite is a first implementation of such a meta DFS tool. It focuses on the generation of graphical modeling tools for graph structures comprising of various types of nodes and edges. Cinco has been very successfully applied to numerous industrial and academic projects, and thus also serves as a proof of concept for the DFS approach itself. The unique combination of the three DFS strategies and Cinco's meta-level approach towards their realization in practice lay the foundation for a new paradigm of software development that is strongly focused on simplicity