HOPE is a (fairly) new workshop that is intended to bring together researchers interested in the design, semantics, implementation, and verification of higher-order effectful programs. It will be informal, consisting of invited talks, contributed talks on work in progress, and open-ended discussion sessions. The HOPE workshops are dedicated to John Reynolds, whose work is an inspiration to us all.


We received 20 high-quality submissions for talk proposals this year, from which the program committee decided to accept 10 for presentation at the workshop. The talks will be videorecorded, and the recordings will be made available here after the workshop.

Also this year, the workshop will feature a special session in memory of John Reynolds. The session will include talks from Olivier Danvy, Robert Harper, Peter O'Hearn, and Uday Reddy, with a mixture of scientific and personal reflections on John's life and work.

Session 1: Concurrent Program Logics
9:00 Impredicative Concurrent Abstract Predicates
Kasper Svendsen and Lars Birkedal
9:30 Subjective Concurrent Protocol Logic
Aleksandar Nanevski, Ruy Ley-Wild, Ilya Sergey, and Germán Andrés Delbianco
10:00 A Separation Logic for Extrinsic Properties of Secure Communication
David Swasey, Derek Dreyer, Deepak Garg, Robert Harper, and Aaron Turon
10:30 Coffee Break

Session 2: Semantics
11:00 A Kripke Logical Relation for Affine Functions: The Story of a Free Theorem in the Presence of Non-termination
Phillip Mates and Amal Ahmed
11:30 Deconstructing General References via Game Semantics
Andrzej Murawski and Nikos Tzevelekos
12:00 Linking Isn't Substitution
Jeremy Siek
12:30 Lunch (NOTE: only one hour for lunch)

Session 3: Special Session in Memory of John Reynolds
1:30 The Essence of Reynolds
Peter O'Hearn
2:00 Adventures of Another Curious Character: John Reynolds in Denmark
Olivier Danvy
2:30 In Memoriam John Reynolds
Robert Harper
3:00 The Essence of Algol: A Retrospective
Uday Reddy
3:30 Coffee Break

Session 4: Types and Verification
4:00 Refinement Types and Algebraic Effects
Danel Ahman
4:30 Adventures in Knot-Tying while Verifying a Thread Library in Coq
Adam Chlipala
5:00 The Ins and Outs of Iteration in Mezzo
Armaël Guéneau, François Pottier, and Jonathan Protzenko
5:30 Attacking the Imperative Relationship Update Problem with Almost Everywhere Heap Invariants
Devin Coughlin and Bor-Yuh Evan Chang


The workshop is sponsored in part by a generous donation from:

Goals of the Workshop

A recurring theme in many papers at ICFP, and in the research of many ICFP attendees, is the interaction of higher-order programming with various kinds of effects: storage effects, I/O, control effects, concurrency, etc. While effects are of critical importance in many applications, they also make it hard to build, maintain, and reason about one's code. Higher-order languages (both functional and object-oriented) provide a variety of abstraction mechanisms to help "tame" or "encapsulate" effects (e.g. monads, ADTs, ownership types, typestate, first-class events, transactions, Hoare Type Theory, session types, substructural and region-based type systems), and a number of different semantic models and verification technologies have been developed in order to codify and exploit the benefits of this encapsulation (e.g. bisimulations, step-indexed Kripke logical relations, higher-order separation logic, game semantics, various modal logics). But there remain many open problems, and the field is highly active.

The goal of the HOPE workshop is to bring researchers from a variety of different backgrounds and perspectives together to exchange new and exciting ideas concerning the design, semantics, implementation, and verification of higher-order effectful programs.

We want HOPE to be as informal and interactive as possible. The program will thus involve a combination of invited talks, contributed talks about work in progress, and open-ended discussion sessions. There will be no published proceedings, but participants will be invited to submit working documents, talk slides, etc. to be posted on this website.

Call for Talk Proposals

We solicit proposals for contributed talks. We recommend preparing proposals of at most 2 pages, in either plain text or PDF format. However, we will accept longer proposals or submissions to other conferences, under the understanding that PC members are only expected to read the first two pages of such longer submissions. When submitting talk proposals, authors should specify how long a talk the speaker wishes to give. By default, contributed talks will be 30 minutes long, but proposals for shorter or longer talks will also be considered. Speakers may also submit supplementary material (e.g. a full paper, talk slides) if they desire, which PC members are free (but not expected) to read.

We are interested in talks on all topics related to the interaction of higher-order programming and computational effects. Talks about work in progress are particularly encouraged. If you have any questions about the relevance of a particular topic, please contact the PC chairs at the address hope2013@mpi-sws.org.

Deadline for talk proposals:     June 14, 2013 (Friday)
Deadline for talk proposals (extended):     July 15, 2013 (Monday)
Notification of acceptance:     July 28, 2013 (Sunday)
Notification of acceptance (updated):     August 2, 2013 (Friday)
Workshop:     September 28, 2013 (Saturday)

The submission website is now closed.

Workshop Organization

Program Co-Chairs Derek Dreyer (MPI-SWS, Germany)
Hongseok Yang (University of Oxford)
Program Committee Anindya Banerjee (IMDEA Software Institute)
Lars Birkedal (Aarhus University)
Aquinas Hobor (National University of Singapore)
Chung-Kil Hur (Microsoft Research Cambridge)
Patricia Johann (Appalachian State University)
Matthew Might (University of Utah)
Peter Müller (ETH Zurich)
Brigitte Pientka (McGill University)
Zhong Shao (Yale University)