sure. you are right; but see, a (Node *) has no information about its (SV *). A workaround would be 
typedef struct treeNode {
   char*  name;
   char*  desc;
   char*  class; //in case we need it
   double branch_length;
   SV* obj; // the perlobj
   SV* obj_ref; // the ref to the perlobj
   struct treeNode *parent;
} Node;

SV* new(char* class, char* name, char* desc, double branch_length) {
   Node* node          = malloc(sizeof(Node));
   node->obj_ref       = newSViv(0);
   node->obj           = newSVrv(obj_ref, class);
   node->class         = savepv(class);
   node->name          = savepv(name);
   node->desc          = savepv(desc);
   node->branch_length = branch_length;
   node->parent        = NULL; // no parent yet
   sv_setiv(node->obj, (IV)node);
   SvREADONLY_on(node->obj);
   return node->obj_ref;
}

SV* get_parent(SV* obj) {
   Node *node = (Node *)SvIV(SvRV(obj));
   if(node != NULL && node->parent != NULL)
      return node->parent->obj_ref;
   else 
      return NULL; // not sure
}

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HTH

In reply to Re^3: Trees using Inline::C by esskar
in thread Trees using Inline::C by rvosa

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