I'll take a stab at this...

I believe you are trying to find out what 'type' the variable node
is.  However, this was encoded ( see Encoder>>init:context:notifying: )
along with a 'code' into the code instance variable of LeafNode.
So, to get at the type you have to decode 'code'.  After decoding
this, compare the type against LdInstType.

So, the short answer appears that you can find this out, that it is
locally encoded into the VariableNode, but that there are currently
no methods in place to make access of this easy.

les