Wed 17 Jul 2019 10:50 - 11:10 at Mancy - Language Design and Implementation Chair(s): John Wickerson

Concurrent programs often make use of future, which are handles to the results of asynchronous operations. Futures provide an instantly available means to communicate not yet computed results, and simplify the implementation of operations that must synchronise on the result of such asynchronous operations. Futures can be characterised as either implicit or explicit, depending on the typing discipline used to type them.

Existing approaches to implementing futures suffer from ``future proliferation'', either at the type-level or at run-time. The former manifests itself through the addition of future type wrappers which expose the client to the asynchronous message indirections of an implementation and hinders subtype polymorphism. The latter manifests itself through increased latency, by traversing nested future structures at run-time. Many languages suffer both kinds.

Previous work offer partial solutions to these problems of future proliferation; in this paper we show how these solutions can be integrated in an elegant and coherent way which is more expressive than either system in isolation. We describe our proposal formally, and state and prove its key properties, in two related calculi, based on the two possible families of future constructs (data-flow futures and control-flow futures). The first calculus relies on static type information to avoid unwanted future creation and the second uses an algebraic data type with dynamic checks. We also discuss how to implement our new system efficiently.

Wed 17 Jul

ecoop-2019-papers
10:30 - 12:10: Research Papers - Language Design and Implementation at Mancy
Chair(s): John WickersonImperial College London
ecoop-2019-papers10:30 - 10:50
Research paper
Shawn MeierUniversity of Colorado, Boulder, Sergio MoverEcole Polytechnique, Bor-Yuh Evan ChangUniversity of Colorado Boulder
DOI Media Attached
ecoop-2019-papers10:50 - 11:10
Research paper
Kiko Fernandez-ReyesUppsala University, Einar Broch JohnsenUniversity of Oslo, Dave ClarkeUppsala Univ. Sweden and KU Leuvern, Ludovic HenrioCNRS, Tobias WrigstadUppsala University
DOI Media Attached
ecoop-2019-papers11:10 - 11:30
Research paper
Daniel A. A. PelsmaekerDelft University of Technology, Netherlands, Hendrik van AntwerpenTU Delft, Eelco VisserDelft University of Technology
DOI Media Attached
ecoop-2019-papers11:30 - 11:50
Research paper
Pascal WeisenburgerTechnische Universität Darmstadt, Guido SalvaneschiTU Darmstadt
DOI Media Attached
ecoop-2019-papers11:50 - 12:10
Research paper
Vlad VerguTU Delft, Eelco VisserDelft University of Technology, Andrew TolmachPortland State University
DOI Media Attached