mlish

An experimental, extensible language inspired by languages like SML and OCaml.

Extensions are type-aware which means that "extensible" includes the type system. In other words, new type system features may be implemented and used as libraries, e.g.:

• type classes
• GADTs
• new pattern match forms

Plain extensions are straightforward as well, e.g., monadic "do" notation

Implemented with Turnstile+ and Racket.