A Theory of Bisimulation for a Fragment of Concurrent ML with Local Names

Concurrent ML is an extension of Standard ML with π-calculus-like primitives for multi-threaded programming. CML has a reduction semantics, but to date there has been no labelled transitions semantics provided for the entire language. In this paper, we present a labelled transition semantics for a fragment of CML called μνCML which includes features not covered before: dynamically generated local channels and thread identifiers. We show that weak bisimulation for μνCML is a congruence, and coincides with barbed bisimulation congruence. We also provide a variant of Sangiorgi’s normal bisimulation for μνCML, and show that this too coincides with bisimulation.