[1608] added more note about AdditionalNodeInfo visibility.

diff --git a/src/lib/datasrc/rbnode_rrset.h b/src/lib/datasrc/rbnode_rrset.h
index a3a2d0ebba815eb88c6940c7541a94a938eafd66..f68791963094ea4fefe8275bce00d36cee936ac8 100644 (file)
--- a/src/lib/datasrc/rbnode_rrset.h
+++ b/src/lib/datasrc/rbnode_rrset.h
@@ -37,8 +37,12 @@ namespace internal {
 struct RBNodeRRsetImpl;
 
 // Forward declaration of an opaque data type defined and used within the
-// implementation.  This is public only because it needs to be used outside
-// of the \c RBNodeRRset class, but conceptually this is a private type.
+// implementation.  This is public only because it needs to be used within
+// the in-memory data source implementation, but conceptually this is a
+// private type for the in-memory data source implementation.
+// Note that the definition of the structure is still hidden within the
+// implementation, so, basically, a normal application should never be able
+// to use it directly even if it peeks into the "internal" namespace.
 struct AdditionalNodeInfo;
 
 /// \brief Special RRset for optimizing memory datasource requirement