[Pl-seminar] 9/26 Seminar: Ross Tate: Towards Gradually Typed Nominal Languages

[Nathaniel Yazdani]

NUPRL Seminar Presents

Ross Tate
Cornell University

2:00PM to 3:00PM
Thursday, September 26th, 2019
Room 366 WVH (http://www.ccs.neu.edu/home/wand/directions.html)

Towards Gradually Typed Nominal Languages

Abstract

Nom demonstrated that efficient and well-behaved gradual typing is possible. But it did so by assuming all code was written using nominal patterns in a simplistic type system. The nominal patterns limit the applicability to existing untyped code, and the simplistic type system limits the applicability to modern industry languages. This talk will present recent results addressing both of these limitations. I will illustrate an implemented design that enables structural patterns to mix with nominal patterns while also providing a variant of the gradual guarantee that ensures interoperability between these patterns and a semantics-preserving migration path from structural patterns into nominal patterns. I will further demonstrate that Nom's design strategy scales to parametric polymorphism, where the key challenge is not actually generic classes or interfaces but rather generic methods and type-argument inference. Although preliminary, experiments suggest that these more expressive designs can still be implemented relatively efficiently, altogether indicating that gradual typing is a viable feature for nominal languages.

Bio

Ross Tate is an Assistant Professor in Computer Science at Cornell University and the Director of the Single Open Intermediate Language Initiative. His research combines theoretical foundations with studies of programmer behavior to develop language designs that ascribe to both academic and industrial principles. He collaborates with major programming languages such as Kotlin, WebAssembly, Julia, Ceylon, and Java to inform his work from practice and incorporate his work into practice. Due to his research contributions and industry impact, he was awarded the Dahl Nygaard Junior Prize in 2017.