Static Typing of Dynamic Languages: A set-theoretic type algebra for the R language

Mardi 17 février 2026
Horaire : 11 h
Mickael Laurent (Université Charles, Prague)

In this presentation, we will see what makes dynamic languages (e.g. Python, Javascript, R) so popular and convenient for prototyping, but also unsafe, hard to maintain and to analyze. These issues can be mitigated by adding static types to these languages, however the current approaches (Typescript, MyPy, Pyright, Pyre, etc.) do not rely on formal and homogeneous foundations, resulting in type systems that offer no formal guarantees and that may exhibit unpredictable behaviors due to the pervasive use of heuristics. We try to design foundations for the typing of dynamic languages, based on the theory of set-theoretic types. We will describe the main features of set-theoretic types, and how they can be used to type generic and overloaded functions. Lastly, we will see how we can go from our general and theoretical framework to a real application to the R language.

Salle 428, couloir 26-00, 4 place Jussieu - 75005 Paris