Abstract

Abstract

Abstract
Dynamic software product lines (DSPLs) combine the advantages of traditional SPLs, such as an explicit variability model connected to an integrated repository of reusable code artefacts, with the ability to exploit a system's variability at runtime. When a system needs to adapt, for example to changes in operational environment or functional requirements, DSPL systems are capable of adapting their behaviour dynamically, thus avoiding the need to halt, recompile and redeploy. The field of DSPL engineering is still in formation and general-purpose DSPL development languages and tools are rare. In this paper we introduce a language and execution environment for developing and running dynamic SPLs. Our work builds on ABS, a language and integrated development environment with dedicated support for implementing static software product lines. Our ABS extension advances the scope of ABS to dynamic SPL engineering. Systems developed using ABS are compiled to Java, and are thus executable on a wide range of platforms. Copyright 2013 ACM.

Abstract

Abstract
Typed models of connector/component composition specify interfaces describing ports of components and connectors. Typing ensures that these ports are plugged together appropriately, so that data can flow out of each output port and into an input port. These interfaces typically consider the direction of data flow and the type of values flowing. Components, connectors, and systems are often parameterised in such a way that the parameters affect the interfaces. Typing such connector families is challenging. This paper takes a first step towards addressing this problem by presenting a calculus of connector families with integer and boolean parameters. The calculus is based on monoidal categories, with a dependent type system that describes the parameterised interfaces of these connectors. As an example, we demonstrate how to define n-ary Reo connectors in the calculus. The paper focusses on the structure of connectors-well-connectedness-and less on their behaviour, making it easily applicable to a wide range of coordination and component-based models. A type-checking algorithm based on constraints is used to analyse connector families, supported by a proof-of-concept implementation.

Abstract
Our department has long been an advocate of the functional-first school of programming and has been teaching Haskell as a first language in introductory programming course units for 20 years. Although the functional style is largely beneficial, it needs to be taught in an enthusiastic and captivating way to fight the unusually high computer science drop-out rates and appeal to a heterogeneous population of students. This paper reports our experience of restructuring, over the last 5 years, an introductory laboratory course unit that trains hands-on functional programming concepts and good software development practices. We have been using game programming to keep students motivated, and following a methodology that hinges on test-driven development and continuous bidirectional feedback. We summarise successes and missteps, and how we have learned from our experience to arrive at a model for comprehensive and interactive functional game programming assignments and a general functionally-powered automated assessment platform, that together provide a more engaging learning experience for students. In our experience, we have been able to teach increasingly more advanced functional programming concepts while improving student engagement.