Professor Eric Van Wyk from the Department of Computer Science and Engineering, University of Minnesota, will give an invited lecture entitled Metatheory for Extensible Languages at UL FRI. You are warmly invited to attend.

The lecture will take place on Thursday, 8 October 2026, at 11:00 in the Graduate Room at UL FRI.

Title:
Metatheory for Extensible Languages

Abstract:
There is a longstanding interest in language extension and mechanisms for easily adding domain-specific features to programming languages. One notion of extensibility argues that language extensions should be independently developed so that programmers can select the extensions needed for a particular task and compose them with a host language. Previously, we developed methods to ensure that the composition of language and extension specifications results in deterministic parsers and well-defined attribute grammars for implementing the language.

Recently, we have been working on establishing a modular approach to reasoning about metatheoretic properties of extensible languages. One goal is to ensure that properties established by a host language continue to hold when language extensions are added. For example, how can a type preservation property introduced by the host language be guaranteed to remain valid when new extensions that perform type checking of their own constructs are incorporated? Another goal is to allow language extensions to introduce new properties that continue to hold when other extensions, unaware of those properties, are added. For instance, an extension that allows variables to be marked as secret or public may seek to establish a property ensuring that secret data never leaks into public variables. How can such a property be maintained in the presence of other extensions? This talk will discuss some initial techniques and tools we have developed to address these challenges.

Biography:
Eric Van Wyk is a Professor in the Department of Computer Science and Engineering at the University of Minnesota. His research focuses on programming languages, particularly extensible languages. He is especially interested in declarative specifications that support the implementation of languages composed from independently developed language extensions and, more recently, in methods for establishing metatheoretic properties of such languages. He earned his Ph.D. from the University of Iowa and completed a postdoctoral appointment at the Oxford Computing Laboratory before joining the University of Minnesota. He is the recipient of an NSF CAREER Award, a McKnight Land-Grant Professorship, and a Charles E. Bower Faculty Teaching Award.