Extensions for Dependent Object Types

The DOT (Dependent Object Types) calculus by Amin et al. (2016) aims to formalizes Scala, specifically, abstract type members and path-dependent types.

This repository contains type-safe extensions to DOT that aim to bridge the gap between DOT and Scala, and to experiment with new Scala features. The extensions are based on our simple type-safety proof, which we started as a fork of the original proof as presented by Amin et al. (2016).

If you want to understand the DOT safety proof, or are interested in creating your own extensions to DOT, you can read our OOPSLA paper, and check out the corresponding Coq proof.

This repo contains:

• the simple DOT safety proof
• extensions of DOT with:
  • paths of arbitrary length (adding type selections on full paths of the form p.A instead of x.A, where p is a path and x is a variable) (proof | paper)
  • mutation (adding mutable references to DOT) (proof | technical report)
  • initialization order (developing a sound initialization order) (proof in progress)