Change reifiedTriple to use subject and object productions instead of ttSubject and ttObject.

Author: gkellogg

etc/turtle.bnf

@@ -26,7 +26,7 @@ iri                   ::= IRIREF | PrefixedName
 PrefixedName          ::= PNAME_LN | PNAME_NS
 BlankNode             ::= BLANK_NODE_LABEL | ANON
 reifier               ::= '~' (iri | BlankNode)?
-reifiedTriple         ::= '<<' ttSubject predicate ttObject reifier* '>>'
+reifiedTriple         ::= '<<' (subject | reifiedTriple) predicate object reifier* '>>'
 tripleTerm            ::= '<<(' ttSubject predicate ttObject ')>>'
 ttSubject             ::=	iri | BlankNode
 ttObject              ::=	iri | BlankNode | literal | tripleTerm

lib/rdf/turtle/reader.rb

@@ -451,17 +451,17 @@ def read_object(subject = nil, predicate = nil)
     ##
     # Read reifiedTriple
     #
-    #      reifiedTriple ::= '<<' ttSubject predicate ttObject reifier? '>>'
+    #      reifiedTriple ::= '<<' (subject | reifiedTriple) predicate object reifier* '>>'
     #
     # @return [RDF::Term]
     def read_reifiedTriple
       return unless @options[:rdfstar]
       if @lexer.first.value == '<<'
         prod(:reifiedTriple) do
           @lexer.shift # eat <<
-          subject = read_ttSubject || error("Failed to parse subject", production: :reifiedTriple, token: @lexer.first)
+          subject = read_ttSubject || read_reifiedTriple || error("Failed to parse subject", production: :reifiedTriple, token: @lexer.first)
           predicate = read_verb || error("Failed to parse predicate", production: :reifiedTriple, token: @lexer.first)
-          object = read_ttObject || error("Failed to parse object", production: :reifiedTriple, token: @lexer.first)
+          object = read_object || error("Failed to parse object", production: :reifiedTriple, token: @lexer.first)
           tt = RDF::Statement(subject, predicate, object, tripleTerm: true)
 
           # An optional reifier. If not specified it is a new blank node.

script/tc

@@ -74,13 +74,13 @@ def run_tc(tc, **options)
       begin
         graph << reader
       rescue Exception => e
+        #require 'byebug'; byebug
         STDERR.puts "Unexpected exception: #{e.inspect}" if options[:verbose]
         result = "failed"
       end
     else
       begin
         graph << reader
-        raise RDF::ReaderError, "triple term" if graph.statements.any? {|s| s.to_a.any?(&:statement?)}
         STDERR.puts "Expected exception" if options[:verbose]
         result = "failed"
       rescue RDF::ReaderError

spec/ntriples_spec.rb

@@ -31,8 +31,6 @@
               else
                 expect {
                   graph << reader
-                  raise RDF::ReaderError, "triple term" if graph.statements.any? {|s| s.to_a.any?(&:statement?)}
-                  #expect(graph.dump(:ntriples).should produce("", t.debug)
                 }.to raise_error RDF::ReaderError
               end
 

spec/reader_spec.rb

@@ -1168,7 +1168,11 @@
                 ex:p1 ex:o1 >>
               ex:p ex:o .
           ),
-          RDF::ReaderError
+          %(
+            _:anon1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#reifies> <<(<http://example/s2> <http://example/p2> <http://example/o2>)>> .
+            _:anon2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#reifies> <<(_:anon1 <http://example/p1> <http://example/o1>)>> .
+            _:anon2 <http://example/p> <http://example/o> .
+          )
         ],
         "IRI identifier":  [
           %(