Séminaire de Zena Ariola le 20 décembre 2012

Zena Ariola, University of Oregon, en visite à PPS pour l'année universitaire en 2012-2013

Titre: Call-by-need: reduction, continuation passing style and abstract machine
Résumé: We introduce the call-by-need calculus and discuss how it represents Wadsworth's graph reduction. We will then present a continuation-passing style (CPS) transformation which brings to light the fact that call-by-need variables are not given meaning by substitution. We relate this CPS to the pi-calculus. We follow with the classical extension which raises issues regarding the sharing of bindings. Two approaches will be discussed, one inspired by natural deduction and the other by the sequent calculus. One example will show how the two semantics differ.