DLS 2016
Tue 1 Nov 2016 Amsterdam, Netherlands
co-located with SPLASH 2016
Tue 1 Nov 2016 10:30 - 10:55 at Matterhorn 1 - Session 2 Chair(s): Gilad Bracha

The type system in the Dart programming language is deliberately designed to be unsound: for a number of reasons, it may happen that a program encounters type errors at runtime although the static type checker reports no warnings. According to the language designers, this ensures a pragmatic balance between the ability to catch bugs statically and allowing a flexible programming style without burdening the programmer with a lot of spurious type warnings.
In this work, we attempt to experimentally validate these design choices. Through an empirical evaluation based on open source programs written in Dart totaling 2.4 M LOC, we explore how alternative, more sound choices affect the type warnings being produced. Our results show that some, but not all, sources of unsoundness can be justified. In particular, we find that unsoundness caused by bivariant function subtyping and method overriding does not seem to help programmers. Such information may be useful when designing future versions of the language or entirely new languages.

Tue 1 Nov
Times are displayed in time zone: Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change

10:30 - 12:10
Session 2DLS at Matterhorn 1
Chair(s): Gilad BrachaGoogle
10:30
25m
Talk
Type Unsoundness in Practice: An Empirical Study of Dart
DLS
Gianluca MezzettiAarhus University, Denmark, Anders MøllerAarhus University, Denmark, Fabio StroccoAarhus University, Denmark
DOI
10:55
25m
Talk
Type Safety Analysis for Dart
DLS
Thomas S. HeinzeAarhus University, Denmark, Anders MøllerAarhus University, Denmark, Fabio StroccoAarhus University, Denmark
DOI
11:20
25m
Talk
Precise and Scalable Static Analysis of jQuery using a Regular Expression Domain
DLS
Changhee ParkKAIST, South Korea, Hyeonseung ImKangwon National University, South Korea, Sukyoung RyuKAIST, South Korea
DOI
11:45
25m
Talk
Just-in-Time Inheritance: A Dynamic and Implicit Multiple Inheritance Mechanism
DLS
Mattias De WaelVrije Universiteit Brussel, Belgium, Janwillem SwalensVrije Universiteit Brussel, Belgium, Wolfgang De MeuterVrije Universiteit Brussel, Belgium
DOI Pre-print File Attached