Lars Birkedal
IT University of Copenhagen

Relational Reasoning for Recursive Types and References


We present a local relational reasoning method for reasoning about contextual equivalence of expressions in a lambda calculus with recursive types and general references. Our development builds on the work of Benton and Leperchey, who devised a nominal semantics and a local relational reasoning method for a language with simple types and simple references. Their method uses a parameterized logical relation. Here we extend their approach to recursive types and general references. For the extension, we build upon Pitts’ and Shinwell’s work on relational reasoning about recursive types (but no references) in nominal semantics.  The extension is non-trivial because of general references (higher-order store) and makes use of some new ideas for proving the existence of the parameterized logical relation and for the choice of parameters.
This is joint work with Nina Bohr.
Host:  Karl Crary
Appointments:  Margaret Weigand <>

Wednesday, October 25, 2006
3:30 p.m.
Wean Hall 8220

Principles of Programming Seminars