get_node_or_nil() must be a lot less expensive to use repeatedly than get_node(), I take it?

Comments are sentances, too.

Space here. Also why should there be so many blank lines?

Do you mean ```Lua = minetest.registered_nodes[minetest.get_node(pos).name] ``` ? Or do you want to change the ignore name to air? If so, then this code won't work as expected either, as it can either return the node information (for the specific position) or node definition.