try NodeHash.find run n
with Not_found -> map_leaf asta in
let (_,qfr),(_,qnr) = q_rec fnode,q_rec nnode (* computed in rec call *)
and lab = Tree.tag tree tnode in
try NodeHash.find run n
with Not_found -> map_leaf asta in
let (_,qfr),(_,qnr) = q_rec fnode,q_rec nnode (* computed in rec call *)
and lab = Tree.tag tree tnode in