ARN string `xml:"CloudFunction"`
}

// Unused. Available for completion.
type topic struct {
	ARN string `xml:"Topic" json:"Topic"`
}

// Config - notification configuration described in
// http://docs.aws.amazon.com/AmazonS3/latest/dev/NotificationHowTo.html
type Config struct {
	XMLNS      string   `xml:"xmlns,attr,omitempty"`
	XMLName    xml.Name `xml:"NotificationConfiguration"`

	if !ok {
		return Error[ErrConfigNotFound]("sub-system %s:%s already deleted or does not exist", subSys, tgt)
	}

	if len(inputs) == 2 {
		currKVS := ck.Clone()
		defKVS := DefaultKVS[subSys]
		for _, delKey := range strings.Fields(inputs[1]) {
			_, ok := currKVS.Lookup(delKey)
			if !ok {
				return Error[ErrConfigNotFound]("key %s doesn't exist", delKey)
			}
			defVal, isDef := defKVS.Lookup(delKey)
			if isDef {