This reminds me that I need to return to my implementation! I maybe bit off a bit more than I could chew by using it as an opportunity to learn D (which is very nice, thanks @WalterBright!) and ended up with a weird bug in my implementation of section 25 "Closures" in the bytecode interpreter, got distracted by Advent of Code and didn't come back to it yet.
Anyway, heartily recommend both working through Crafting Interpreters and learning the D language.
Anyway, heartily recommend both working through Crafting Interpreters and learning the D language.