anchor.diff:  [source,java]
   ----
   Prefix foaf = SparqlBuilder.prefix("foaf", iri("http://xmlns.com/foaf/0.1/"));
  -Variable x = SparqlBuilder.var("x"), name = Spanqit.var("name");
  +Variable x = SparqlBuilder.var("x"), name = SparqlBuilder.var("name");
   
   TriplePattern triple = x.has(foaf.iri("nick"), Rdf.literalOf("Alice"), Rdf.literalOf("Alice_"))
       .andHas(foaf.iri("name"), name);
  
positive.code: = Graph Patterns
  SparqlBuilder uses three classes to represent the SPARQL graph patterns, all of which implement the {javadoc}sparqlbuilder/graphpattern/GraphPatter.html[GraphPattern] interface:
  - The `TriplePattern` class represents triple patterns.
  - The `GraphPatternNotTriple` class represents collections of graph patterns.
  - The `SubSelect` class represents a SPARQL sub query.
  
negative.code: ----
  Prefix dc10 = SparqlBuilder.prefix("dc10", iri("http://purl.org/dc/elements/1.0/")),
  	dc11 = SparqlBuilder.prefix("dc11", iri("http://purl.org/dc/elements/1.1/"));
  Variable book = SparqlBuilder.var("book"), title = SparqlBuilder.var("title");
  
  GraphPatternNotTriple union = GraphPatterns.union(book.has(dc10.iri("title"), title),
  	book.has(dc11.iri("title"), title);
  