Constraints for Free in Concurrent Computation

We investigate concurrency as unifying computational paradigm which integrates functional, constraint, and object-oriented programming. We propose the ρ-calculus as a uniform foundation of concurrent computation and formally relate it to other models: The ρ calculus with equational constraints provides for logic variables and is bisimilar to the γ-calculus. The ρ-calculus without constraints is a proper subset of the π-calculus. We prove its Turing completeness by embedding the eager λ-calculus in continuation passing style. The ρ-calculus over an arbitrary constraint system is an extension of the standard cc-model with procedural abstraction.

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