Continuations for Prototyping Concurrent Languages

We have recently introduced the “continuation semantics for concurrency” (CSC) technique in an attempt to exploit the benefits of using continuations in concurrent systems development. In the CSC approach, a continuation is an application-dependent configuration of computations (partially evaluated denotations). Every computation or group of computations contained in a continuation can be accessed and manipulated separately by the denotational semantic function. The CSC technique provides excellent flexibility and a “pure” continuation-based approach to communication and concurrency, in which all control concepts are modeled as operations manipulating continuations. In this paper, we present a methodology for concurrent language development, based on denotational semantics. We show that, by using the CSC technique, denotational semantics can be used both as a method for formal specification and design and as a general method for implementing compositional prototypes of concurrent programming languages. We provide continuation structures for various traditional concurrent control concepts. We also present compositional semantic models for the following advanced control concepts that have not been modeled until now without CSC: remote object (process) destruction and cloning and nondeterministic promotion in Andorra-like languages.