SPLASH 2020
Sun 15 - Sat 21 November 2020 Online Conference
Tue 17 Nov 2020 15:20 - 15:40 at SPLASH-I - T-5 Chair(s): Raffi Khatchadourian, Tyler Sorensen
Wed 18 Nov 2020 03:20 - 03:40 at SPLASH-I - T-5 Chair(s): Burcu Kulahcioglu Ozkan, Reuben Rowe

There is a large gap between the specification of type systems and the implementation
of their type checkers, which impedes reasoning about the soundness of the type checker with respect to the specification.
A vision to close this gap is to automatically obtain type checkers from declarative programming language specifications.
This moves the burden of proving correctness from a case-by-case basis for concrete languages
to a single correctness proof for the specification language.
This vision is obstructed by an aspect common to all programming languages: name resolution.
Naming and scoping are pervasive and complex aspects of the static semantics of programming languages.
Implementations of type checkers for languages with name binding features such as modules,
imports, classes, and inheritance interleave collection of binding information (i.e., declarations, scoping structure, and imports)
and querying that information.
This requires scheduling those two aspects in such a way that query answers are stable—i.e.,
they are computed only after all relevant binding structure has been collected.
Type checkers for concrete languages accomplish stability using language-specific knowledge about the type system.

In this paper we give a language-independent characterization of necessary and sufficient conditions to guarantee
stability of name and type queries during type checking in terms of \emph{critical edges in an incomplete scope graph}.
We use critical edges to give a formal small-step operational semantics
to a declarative specification language for type systems, that achieves soundness by delaying queries that may depend on missing information.
This yields type checkers for the specified languages that are sound by construction—i.e.,
they schedule queries so that the answers are stable, and only accept programs that are name- and type-correct according to the declarative language specification.
We implement this approach, and evaluate it against specifications of a small module and record language,
as well as subsets of Java and Scala.

Tue 17 Nov
Times are displayed in time zone: Central Time (US & Canada) change

15:00 - 16:20: T-5OOPSLA at SPLASH-I +12h
Chair(s): Raffi KhatchadourianCity University of New York, Tyler SorensenUniversity of California at Santa Cruz
15:00 - 15:20
Talk
OOPSLA
Mehdi BagherzadehOakland University, Nicholas FiremanOakland University, Anas ShaweshOakland University, Raffi KhatchadourianCity University of New York
Link to publication DOI Pre-print Media Attached
15:20 - 15:40
Talk
OOPSLA
Arjen RouvoetDelft University of Technology, Hendrik van AntwerpenDelft University of Technology, Casper Bach PoulsenDelft University of Technology, Robbert KrebbersRadboud University Nijmegen, Eelco VisserDelft University of Technology
Link to publication DOI Pre-print Media Attached
15:40 - 16:00
Talk
OOPSLA
Quentin StiévenartVrije Universiteit Brussel, Magnus MadsenAarhus University
Link to publication DOI Media Attached
16:00 - 16:20
Talk
OOPSLA
Lenka TuroňováBrno University of Technology, Lukáš HolíkBrno University of Technology, Ondřej LengálBrno University of Technology, Olli SaarikiviMicrosoft, Margus VeanesMicrosoft, Tomáš VojnarBrno University of Technology
Link to publication DOI Media Attached

Wed 18 Nov
Times are displayed in time zone: Central Time (US & Canada) change

03:00 - 04:20: T-5OOPSLA at SPLASH-I
Chair(s): Burcu Kulahcioglu OzkanMPI-SWS, Reuben RoweUniversity College London
03:00 - 03:20
Talk
OOPSLA
Mehdi BagherzadehOakland University, Nicholas FiremanOakland University, Anas ShaweshOakland University, Raffi KhatchadourianCity University of New York
Link to publication DOI Pre-print Media Attached
03:20 - 03:40
Talk
OOPSLA
Arjen RouvoetDelft University of Technology, Hendrik van AntwerpenDelft University of Technology, Casper Bach PoulsenDelft University of Technology, Robbert KrebbersRadboud University Nijmegen, Eelco VisserDelft University of Technology
Link to publication DOI Pre-print Media Attached
03:40 - 04:00
Talk
OOPSLA
Quentin StiévenartVrije Universiteit Brussel, Magnus MadsenAarhus University
Link to publication DOI Media Attached
04:00 - 04:20
Talk
OOPSLA
Lenka TuroňováBrno University of Technology, Lukáš HolíkBrno University of Technology, Ondřej LengálBrno University of Technology, Olli SaarikiviMicrosoft, Margus VeanesMicrosoft, Tomáš VojnarBrno University of Technology
Link to publication DOI Media Attached