# File lib/rdf/redland/node.rb, line 150
    def Node.ensure(node)
      case node
      when Node
        my_node = Redland.librdf_new_node_from_node(node.node)
      when SWIG::TYPE_p_librdf_node_s
        my_node = Redland.librdf_new_node_from_node(node)
      when Uri
        my_node = Redland.librdf_new_node_from_uri($world.world,node.uri)
      when URI
        my_node = Redland.librdf_new_node_from_uri_string($world.world,node.to_s)
      else
        my_node = nil
      end
      return my_node
    end