SPLASH 2020
Sun 15 - Sat 21 November 2020 Online Conference
Tue 17 Nov 2020 09:40 - 10:00 at SPLASH-I - T-2 Chair(s): Karim Ali, Aritra Sengupta
Tue 17 Nov 2020 21:40 - 22:00 at SPLASH-I - T-2 Chair(s): Yaoda Zhou, Iulian Neamtiu

Pressed by the difficulty of writing asynchronous, event-driven code, mainstream languages have recently been building in support for a variety of advanced control-flow features. Meanwhile, experimental language designs have suggested effect handlers as a unifying solution to programmer-defined control effects, subsuming exceptions, generators, and async–await. However, despite these trends, complex control flow—in particular, control flow that exhibits a bidirectional pattern—remains challenging to manage.

We introduce bidirectional algebraic effects, a new programming abstraction that supports bidirectional control transfer in a more natural way. Handlers of bidirectional effects can raise further effects to transfer control back to the site where the initiating effect was raised, and can use themselves to handle their own effects. We present applications of this expressive power, which falls out naturally as we push toward the unification of effectful programming with object-oriented programming. We pin down the mechanism and the unification formally using a core language that makes generalizations to effect operations and effect handlers.

The usual propagation semantics of control effects such as exceptions conflicts with modular reasoning in the presence of effect polymorphism—it breaks parametricity. Bidirectionality exacerbates the problem. Hence, we set out to show the core language, which builds on the existing tunneling semantics for algebraic effects, is not only type-safe (no effects go unhandled), but also abstraction-safe (no effects are accidentally handled). We devise a step-indexed logical-relations model, and construct its parametricity and soundness proofs. These core results are fully mechanized in Coq. While a full-featured compiler is left to future work, experiments show that as a first-class language feature, bidirectional handlers can be implemented efficiently.

Tue 17 Nov

Displayed time zone: Central Time (US & Canada) change

09:00 - 10:20
T-2OOPSLA at SPLASH-I +12h
Chair(s): Karim Ali University of Alberta, Aritra Sengupta Amazon Web Services, USA
09:00
20m
Talk
Formulog: Datalog for SMT-Based Static Analysis
OOPSLA
Aaron Bembenek Harvard University, Michael Greenberg Pomona College, Stephen Chong Harvard University
Link to publication DOI Media Attached
09:20
20m
Talk
A Large-Scale Longitudinal Study of Flaky Tests
OOPSLA
Wing Lam University of Illinois at Urbana-Champaign, Stefan Winter TU Darmstadt, Anjiang Wei Peking University, Tao Xie Peking University, Darko Marinov University of Illinois at Urbana-Champaign, Jonathan Bell Northeastern University
Link to publication DOI Media Attached
09:40
20m
Talk
Handling Bidirectional Control Flow
OOPSLA
Yizhou Zhang University of Waterloo, Guido Salvaneschi University of St. Gallen, Andrew C. Myers Cornell University
Link to publication DOI Media Attached
10:00
20m
Talk
WATCHER: In-Situ Failure Diagnosis
OOPSLA
Hongyu Liu Purdue University, Sam Silvestro University of Texas at San Antonio, Xiangyu Zhang Purdue University, Jian Huang University of Illinois at Urbana-Champaign, Tongping Liu University of Massachusetts at Amherst
Link to publication DOI Media Attached
21:00 - 22:20
T-2OOPSLA at SPLASH-I
Chair(s): Yaoda Zhou University of Hong Kong, Iulian Neamtiu New Jersey Institute of Technology
21:00
20m
Talk
Formulog: Datalog for SMT-Based Static Analysis
OOPSLA
Aaron Bembenek Harvard University, Michael Greenberg Pomona College, Stephen Chong Harvard University
Link to publication DOI Media Attached
21:20
20m
Talk
A Large-Scale Longitudinal Study of Flaky Tests
OOPSLA
Wing Lam University of Illinois at Urbana-Champaign, Stefan Winter TU Darmstadt, Anjiang Wei Peking University, Tao Xie Peking University, Darko Marinov University of Illinois at Urbana-Champaign, Jonathan Bell Northeastern University
Link to publication DOI Media Attached
21:40
20m
Talk
Handling Bidirectional Control Flow
OOPSLA
Yizhou Zhang University of Waterloo, Guido Salvaneschi University of St. Gallen, Andrew C. Myers Cornell University
Link to publication DOI Media Attached
22:00
20m
Talk
WATCHER: In-Situ Failure Diagnosis
OOPSLA
Hongyu Liu Purdue University, Sam Silvestro University of Texas at San Antonio, Xiangyu Zhang Purdue University, Jian Huang University of Illinois at Urbana-Champaign, Tongping Liu University of Massachusetts at Amherst
Link to publication DOI Media Attached