Continuing into the future: On the interaction of futures and first-class continuations

  • Morry Katz
  • Daniel Weise
Part I Parallel Lisp Languages and Programming Models
Part of the Lecture Notes in Computer Science book series (LNCS, volume 441)


One of the nicest features of the future construct originally presented in Multilisp [2] is its near orthogonality with respect to a functional subset of Scheme [1]. Introducing futures into most functional programs does not affect the value returned, even though the parallel execution order might differ from the sequential. When futures and continuations are used in the same program, however, parallel and sequential executions can yield different results. No existing implementation of futures has yet addressed this issue. We make futures and continuations interact properly through a simple, yet important, change to the implementation of the future construct. This change causes a second problem to manifest itself: the creation of extraneous computation threads. The second problem is addressed by making an additional change to the future construct.

2 References

  1. [1]
    H. Abelson, et. al. Revised3 Report on the Algorithmic Language Scheme. MIT AI Memo 848a.Google Scholar
  2. [2]
    Robert H. Halstead, Jr. Multilisp: A Language for Concurrent Symbolic Computation. ACM Transactions on Programming Languages and Systems 7,4 (Oct. 1985), 501–538.Google Scholar
  3. [3]
    Robert H. Halstead, Jr. New Ideas in Parallel Lisp: Language Design, Implementation, and Tools. Paper presented at the U.S./Japan Workshop on Parallel Lisp, Sendai, Japan, June 1989, to be published in Lecture Notes in Computer Science, Springer-Verlag, Berlin.Google Scholar
  4. [4]
    Morry Katz and Daniel Weise. Continuing Into the Future: On the Interaction of Futures and First-Class Continuations. To be published in Proceedings of the 1990 ACM Conference on Lisp and Functional Programming.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • Morry Katz
  • Daniel Weise

There are no affiliations available

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