FSCAFI: A Core Calculus for Collective Adaptive Systems Programming

A recently proposed approach to the rigorous engineering of collective adaptive systems is the aggregate computing paradigm, which operationalises the idea of expressing collective adaptive behaviour by a global perspective as a functional composition of dynamic computational fields (i.e., structures mapping a collection of individual devices of a collective to computational values over time). In this paper, we present FSCAFI, a core language that captures the essence of exploiting field computations in mainstream functional languages, and which is based on a semantic model for field computations leveraging the novel notion of "computation against a neighbour". Such a construct models expressions whose evaluation depends on the same evaluation that occurred on a neighbour, thus abstracting communication actions and, crucially, enabling deep and straightforward integration in the Scala programming language, by the SCAFI incarnation. We cover syntax and informal semantics of FScaFi, provide examples of collective adaptive behaviour development in SCAFI, and delineate future work.