This discussion centers around the potential addition of refinement types to the Rust programming language, particularly following recent updates in Rust such as const generics. The comments highlight a few interesting mechanisms that could facilitate this enhancement, such as a canonicalization process for types that would simplify and reduce equivalent units without requiring later checks for equivalency. Furthermore, suggestions include the use of type refinements to better handle various units, conversions, and support for common conceptual categories like length, color, currencies, and languages. The consensus among commenters suggests a strong interest in advancing type systems in Rust, indicating that enhancement in this area could foster more robust and type-safe programming practices.