> The point of Go's error handling is that it isn't magic.
The problem is first, that sum types are also not magic. There is nothing special about the error type or value in a `Either<T, Err>`. Go's type system is just too crappy to make such things, or make good use of them even after you tried to shove them into an interface{}.
The second problem is that Go's error values, like every error handling system that pretends it doesn't need sum types, have picked up more magic (%w) or impacted the usability of other interfaces (context.Err, separate error channels) bit by bit.
The problem is first, that sum types are also not magic. There is nothing special about the error type or value in a `Either<T, Err>`. Go's type system is just too crappy to make such things, or make good use of them even after you tried to shove them into an interface{}.
The second problem is that Go's error values, like every error handling system that pretends it doesn't need sum types, have picked up more magic (%w) or impacted the usability of other interfaces (context.Err, separate error channels) bit by bit.