Isn’t a Maybe enum equivalent to just using a return value of, for example, int | null
with type warnings?
Not quite, because the Maybe enum is neither int nor null, but it’s own, third thing. So before you can do any operations with the return value, you need to handle both cases that could occur
Isn’t that also true with compile-time type checking though? Eg. 0 + x where x is int|null would be detected? I don’t have much experience here so I could be wrong but I can’t think of a case where they’re not equivalent
Most languages that let you do ambiguous return types don’t do compile-time type checking, and vice versa. But if it’s actually implemented that way, then it’s logically equivalent, you’re right. Still, I prefer having things explicit