I rarely use Either. If logic is internal to my program, often the cause of the deviation from the happy path is implicit, and I can just use Option. But if I d

I rarely use Either. If logic is internal to my program, often the cause of the deviation from the happy path is implicit, and I can just use Option. But if I do want to propagate the cause, usually I prefer to model directly within my types as a sealed trait, because then I can easily model multiple causes. Of course, this comes up short if I want to reuse the same cause for multiple distinct outcomes. Either could be nice for this, but it comes up short for multiple causes, because you have to resort to nested Either. Consequently, I very rarely use Either. What I'd really like is a simple type union syntax, so I could union the happy path result with any number of failure modes, where there isn't necessarily a common supertype for anything.