<http://localhost/code#vars/a_null>	<http://localhost/code#name>	"a" .
<http://localhost/code#vars/a_null>	<http://localhost/code#version>	"0"^^<http://www.w3.org/2001/XMLSchema#int> .
<http://localhost/code#vars/a_null>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://localhost/code#Variable> .