Computation in focused intuitionistic logic

Abstract

We investigate the control of evaluation strategies in a variant of the Λ-calculus derived through the Curry-Howard correspondence from LJF, a sequent calculus for intuitionistic logic implementing the focusing technique. The proof theory of focused intuitionistic logic yields a single calculus in which a number of known Λ-calculi appear as subsystems obtained by restricting types to a certain fragment of LJF. In particular, standard Λ-calculi as well as the call-by-push-value calculus are analysed using this framework, and we relate cut elimination for LJF to a new abstract machine subsuming well-known machines for these different strategies.