let new_node s =
incr cpt_nodes;
cpt_process := max !cpt_process (List.length (Node.variables s));
if not quiet then
begin
printf "node @{<b>%d@}: " !cpt_nodes;
if verbose < 1 then printf "@[%a@]@." Node.print_history s
else printf "@[%a@] =@\n @[%a@]@." Node.print_history s Node.print s
end;
if dot then Dot.new_node s