local nullfunc = function (n) return n end
local to_node = (Dnode ~= node) and Dnode.tonode or nullfunc
local to_direct = (Dnode ~= node) and Dnode.todirect or nullfunc
local nullfunc = function (n) return n end
local to_node = (Dnode ~= node) and Dnode.tonode or nullfunc
local to_direct = (Dnode ~= node) and Dnode.todirect or nullfunc