SCCharts Twelve Years Later: A Reflection on Sequential Constructiveness and Text-First Modeling (Keynote)

The SCCharts language, first publicly presented 2013 at Dagstuhl Seminar 13471 on Synchronous Programming and subsequently at PLDI’14, originated from a collaboration with an industrial partner, National Instruments (NI), as well as other academic researchers, notably Michael Mendler (U Bamberg) and Partha Roop (U Auckland). Simply put, the task put forward by NI was to develop a graphical, Statecharts-like language for hardware synthesis, with a ”clean” semantics. The synchronous model of computation, as embodied in several textual and graphical languages, seemed attractive due to its solid foundation, including deterministic concurrency. However, the policy for shared variable accesses in classical synchronous programming, possibly leading to hard-to-track ”causality errors” at compile time, was seen as rather restrictive.