Retractions in Intersection Types

Mario Coppo, Mariangiola Dezani-Ciancaglini, Alejandro Díaz-Caro, Ines Margaria, Maddalena Zacchi
2017 Electronic Proceedings in Theoretical Computer Science  
This paper deals with retraction - intended as isomorphic embedding - in intersection types building left and right inverses as terms of a lambda calculus with a bottom constant. The main result is a necessary and sufficient condition two strict intersection types must satisfy in order to assure the existence of two terms showing the first type to be a retract of the second one. Moreover, the characterisation of retraction in the standard intersection types is discussed.
doi:10.4204/eptcs.242.5 fatcat:mmtrzshdmvecxpb44piyhcrmxu