An Error
object represents the state and handling of instance
or middleware errors.
errors
Returns a list of errors, if any.
occured
Returns TRUE if any error has occurred, FALSE otherwise.
set(err)
Sets an error.
set()
Error$set(err)
clone()
The objects of this class are cloneable with this method.
Error$clone(deep = FALSE)
deep
Whether to make a deep clone.