This paper describes a reduction from the halting problem of Turing machines to subtype checking in Java. It follows that subtype checking in Java is undecidable, which answers a question posed by Kennedy and Pierce in 2007. It also follows that Java’s type checker can recognize any recursive language, which improves a result of Gill and Levy from 2016. The latter point is illustrated by a parser generator for fluent interfaces.
Wed 18 Jan Times are displayed in time zone: (GMT+02:00) Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change
|10:30 - 10:55|
|10:55 - 11:20|
Radu GrigoreUniversity of Kent
|11:20 - 11:45|
|11:45 - 12:10|
Karl CraryCarnegie Mellon University