HKU PL Group

We are a group of programming language researchers who study topics about functional language design, type theory, compilers and program analysis.
The University of Hong Kong

Flow-sensitive typing for isomorphic expressions


Flow typing or occurrence typing specializes the type of an expression in a type-case analysis. It has been implemented in some modern programming languages including Ceylon, Typescript, Flow and Racket etc. Flow typing has various practical applications such as safe type-casting and detecting null deference at compile time. In this talk we will talk about flow-typing and if it could be extended to deal with equivalent variables or expressions.