2015-01-22: James Chapman (Institute of Cybernetics, Tallinn)

Tue, 14 Oct 2025 16:51:42 +0000

James Chapman (Institute of Cybernetics, Tallinn)

Termination, later

Abstract

It would be a great shame if dependently-typed programming (DTP) restricted us to only writing very clever programs that were a priori structurally recursive and hence obviously terminating. Put another way, it is a lot to ask of the programmer to provide the program and its termination proof in one go, programmers should also be supported in working step-by-step. I will show a technique that lowers the barrier of entry, from showing termination to only showing productivity up front, and then later providing the opportunity to show termination (convergence). I will show an example of a normaliser for STLC represented in Agda as a potentially non-terminating but nonetheless productive corecursive function targeting the coinductive delay monad.

(Joint work with Andreas Abel)

2015-01-22 11:00:00 UTC
LT1310