Technically, if you use `fmt.Errorf`, then the caller can't get anything useful out of your errors.
Types are promises. All the `error` interface promises is a string representation. I acknowledge that most of the time there is more information available. However, from the function signature _alone_, you wouldn't know. I understand that this is more of a theoretical problem then a practical problem but it still holds (in my opinion).
It's mostly false.
Technically, if you use `fmt.Errorf`, then the caller can't get anything useful out of your errors.
Types are promises. All the `error` interface promises is a string representation. I acknowledge that most of the time there is more information available. However, from the function signature _alone_, you wouldn't know. I understand that this is more of a theoretical problem then a practical problem but it still holds (in my opinion).