In 2020, I released Cubiml, showing how to combine full type inference with structural subtyping in an ML-like language, and earlier this year, I followed it up with PolySubML, extending it with higher rank types and existential types among other features. For my next language (which I’ll call X here, since I haven’t chosen a name yet), I set the ambitious goal of supporting all of OCaml’s most notable functionality on top of everything PolySubML already supports. In this post, I will t...| Considerations on Codecrafting