Semantic Analysis of Normalisation for Directional Logic Programming

This video presents a research talk from the WITS 2025 workshop (Workshop on Implementation of Type Systems) exploring the semantic analysis of normalization for directional logic programming. Delivered by Vikraman Choudhury, Neel Krishnaswami, and Ariadne Si Suo from Università di Bologna & Inria OLAS and the University of Cambridge, the presentation examines how directional logic programming can provide foundations for mode-correct bidirectional type systems. Learn about their approach using Reddy's calculus (1993), which adapts Abramsky's Linear Chemical Abstract Machine to create a typed calculus for directional logic programs. The researchers present a categorical semantics using polycategories and demonstrate normalization results showing how logic queries can be evaluated to normal forms, determining whether queries fail or succeed through output substitutions. The 25-minute talk was presented at the ACM SIGPLAN-sponsored WITS workshop on January 20, 2025, as part of the POPL 2025 conference.