Abstract How to Add Threads to a Sequential Language Without Getting Tangled Up

It is possible to integrate Scheme-style first-class continuations and threads in a systematic way. We expose the design choices, discuss their consequences, and present semantical frameworks that specify the behavior of Scheme programs in the presence of threads. While the issues concerning the addition of threads to Schemelike languages are not new, many questions have remained open. Among the pertinent issues are the exact relationship between continuations and the call-with-current-continuation primitive, the interaction between threads, first-class continuations, and dynamic-wind, the semantics of dynamic binding in the presence of threads, and the semantics of thread-local store. Clarifying these issues is important because the design decisions related to them have profound effects on the programmer’s ability to write modular abstractions. 1 What’s in a Continuation