We propose a logic for true concurrency whose formulae predicate about events in computations and their causal dependencies. The induced logical equivalence is hereditary history preserving bisimilarity, and fragments of the logic can be identified which correspond to other true concurrent behavioural equivalences in the literature: step, pomset and history preserving bisimilarity. Standard Hennessy-Milner logic and thus (interleaving) bisimilarity are also recovered as a fragment. We believe that this contributes to a rational presentation of the true concurrent spectrum and to a deeper understanding of the relations between the involved behavioural equivalences
Abstract. Boxed Ambients (BA) replace Mobile Ambients'open capability with communication primitives acting across ambient boundaries. Expressiveness is achieved at the price of communication interferences on message reception whose resolution requires synchronisation of activities at multiple, distributed locations. We study a variant of BA aimed at controlling communication interferences as well as mobility ones. Our calculus draws inspiration from Safe Ambients (SA) (with passwords) and modifies the communication mechanism of BA. Expressiveness is maintained through a new form of co-capability that at the same time registers incoming agents with the receiver ambient and performs access control.
Abstract. We give a compositional event structure semantics of the π-calculus. The main issues to deal with are the communication of free names and the extrusion of bound names. These are the source of the expressiveness of the π-calculus, but they also allow subtle forms of causal dependencies. We show that free name communications can be modeled in terms of "incomplete/potential synchronization" events. On the other hand, we argue that it is not possible to satisfactorily model parallel extrusion within the framework of stable event structures. We propose to model a process as a pair (E, X) where E is a prime event structure and X is a set of (bound) names. Intuitively, E encodes the structural causality of the process, while the set X affects the computation on E so as to capture the causal dependencies introduced by scope extrusion. The correctness of our true concurrent semantics is shown by an operational adequacy theorem with respect to the standard late semantics of the π-calculus.
To cite this version:Silvia Crafa, Luca Padovani. The chemical approach to typestate-oriented programming. To appear in the proceedings of OOPSLA 2015of OOPSLA . 2015 The chemical approach to typestate-oriented programming
AbstractWe study a novel approach to typestate-oriented programming based on the chemical metaphor: state and operations on objects are molecules of messages and state transformations are chemical reactions. This approach allows us to investigate typestate in an inherently concurrent setting, whereby objects can be accessed and modified concurrently by several processes, each potentially changing only part of their state. We introduce a simple behavioral type theory to express in a uniform way both the private and the public interfaces of objects, to describe and enforce structured object protocols consisting of possibilities, prohibitions, and obligations, and to control object sharing.
Abstract. We propose the first compositional event structure semantics for a very expressive π-calculus, generalising Winskel's event structures for CCS. The π-calculus we model is the πI-calculus with recursive definitions and summations. First we model the synchronous calculus, introducing a notion of dynamic renaming to the standard operators on event structures. Then we model the asynchronous calculus, for which a new additional operator, called rooting, is necessary for representing causality due to new name binding. The semantics are shown to be operationally adequate and sound with respect to bisimulation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.