datastore: add docs about flatten, LoadStruct and slices
We don't currently support an Inner struct implementing
PropertyLoadSaver by using LoadStruct() if the Outer struct uses the
`flatten` tag for the Inner struct.
fixes
@@ -308,8 +308,9 @@ an Outer's properties would be equivalent to those of:
Z bool
}
-Note that the "flatten" option cannot be used for Entity value fields.
-The server will reject any dotted field names for an Entity value.
+Note that the "flatten" option cannot be used for Entity value fields or
+PropertyLoadSaver implementers. The server will reject any dotted field names
+for an Entity value.
The PropertyLoadSaver Interface
