Abstract
Conceived and developed at the same time as the other synchronous languages, Signal, with hindsight, seems to stand out from the crowd. It is dedicated to "open" systems and focuses on synchronization and clocks. The synchronization of a program is synthesized, not verified. The presentation explained the principles of this approach, starting with the computation of clocks and causality, which provides a notion of temporal interface useful for modular compilation. Beyond the presentation of the language, the aim was to show the interest of these principles. The presentation explained how to exploit recent advances in proof techniques to increase the power of clock computation. And, above all, it explained how an extension of the causal calculus can be used to handle programs including numerical constraints, a useful extension when we're interested in modeling physical systems.
