Follow-up to Method on Emulating Higher-Kinded Types (HKTs) in Rust
First off, thanks for all the comments and kind words on the original writeup; I've been meaning to follow up on some of the suggestions and write about the different ways to represent monads (and functors, HKTs, etc) that now exist, but a month of being busy has kind of gotten in the way (mainly with three new kittens!).
And for sure, I do not expect (nor do I want) this to become the norm for production-level Rust: rather, I hope that this can contribute to the foundations of programming with higher-level abstractions in Rust, somewhat like how early template metaprogramming in C++ and typeclass-constraint-unification metaprogramming in Haskell have contributed, perhaps indirectly, to later innovations in their respective languages and ecosystems that were much more reasoned, sound and usable.
Changes, Edits, Refinements
One of the things suggested in the com