str_enum
A real simple declarative macro that I have ended up copy pasting into a few of my projects, spruced up with a couple features to make it more flexible.
Unless you're a real stickler for compile times you're probably fine with strum over this for more features.
It implements basically everything str does, minus the derives which are opt-in. So you can probably use this anywhere you use &str.
use str_enum;
str_enum!