docker/daemon/daemon_transport.go
func (ref daemonReference) PolicyConfigurationNamespaces() []string {
	// See the explanation in daemonReference.PolicyConfigurationIdentity.
	switch {
	case ref.id != "":
		return []string{}
	case ref.ref != nil:
		return policyconfiguration.DockerReferenceNamespaces(ref.ref)
	default: // Coverage: Should never happen, NewReference above should refuse such values.
		panic("Internal inconsistency: daemonReference has empty id and nil ref")
	}
}
func (ref daemonReference) PolicyConfigurationNamespaces() []string {
	// See the explanation in daemonReference.PolicyConfigurationIdentity.
	switch {
	case ref.id != "":
		return []string{}
	case ref.ref != nil:
		return policyconfiguration.DockerReferenceNamespaces(ref.ref)
	default: // Coverage: Should never happen, NewReference above should refuse such values.
		panic("Internal inconsistency: daemonReference has empty id and nil ref")
	}
}
// PolicyConfigurationNamespaces returns a list of other policy configuration namespaces to search
// for if explicit configuration for PolicyConfigurationIdentity() is not set.  The list will be processed
// in order, terminating on first match, and an implicit "" is always checked at the end.
// It is STRONGLY recommended for the first element, if any, to be a prefix of PolicyConfigurationIdentity(),
// and each following element to be a prefix of the element preceding it.