Subtyping recursion and parametric polymorphism in kernel fun

@article{Colazzo2005SubtypingRA,
  title={Subtyping recursion and parametric polymorphism in kernel fun},
  author={Dario Colazzo and Giorgio Ghelli},
  journal={Inf. Comput.},
  year={2005},
  volume={198},
  pages={71-147}
}
We study subtype checking for recursive types in system kernel Fun, a typed λcalculus with subtyping and bounded second-order polymorphism. Along the lines of [AC93], we define a subtype relation over kernel Fun recursive types, and prove it to be transitive. We then show that the natural extension of the algorithm introduced in [AC93] to compare first-order recursive types yields a non complete algorithm. Finally, we prove the completeness and correctness of a different algorithm, which lends… CONTINUE READING