
Type safety for core Scala – based on Definitional Interpreters - jedharris
http://lambda-the-ultimate.org/node/5270
======
jedharris
Also! I did not know that Odersky & associates are working on a clean
reimplementation of Scala called "Dotty" that is named after exactly this kind
of type theory (Dependent Object Types or DOT).

They just got their compiler to self-host, see
[https://github.com/lampepfl/dotty](https://github.com/lampepfl/dotty) and
[http://www.scala-lang.org/blog/2015/10/23/dotty-compiler-
boo...](http://www.scala-lang.org/blog/2015/10/23/dotty-compiler-
bootstraps.html)

------
jedharris
The first formal type system that works for (simplified) Scala.

More generally, shifting from term rewriting to operational semantics (i.e.
proving interpreters correct) seems like a big improvement. Instead of working
in a completely different semantic domain, we work in one closely allied to
our implementations.

------
jedharris
As the post says at the bottom, this solves a problem that has been open for
over a decade.

