Hi, after a conversation at work, where we wanted an Option type but with clear meanings for what the None variant made, I quickly hacked up the Enumizer crate - a crate with macros that create Option/Result/Either equivalent types, with user-chosen variant names. The crate is still far from complete - I implemented the functions that I thought are must-have, but there's still plenty to do, if anyone wants to contribute :)

<edit> I'm seeing from the discussion below that this might not be as clear as I imagined it to be :)

Let's say that you have a mechanism that has an expensive lookup for values, but also has some cache for recently viewed values. If you just return Option<Value> from both search types, it's hard to disambiguate whether a None means that the value was missing from the cache, or is actually missing. With this you can add to your code alias_option!(Cache, Hit, Miss); and alias_option!(Lookup, Found, NotExisting);, and you'll generate these types and avoid ambiguity by the power of type checking, while also having more readable code.

enum Cache<T> { Hit(T), Miss } enum Lookup<T> { Found(T), NotExisting }