_nt_node_class_expression (Treetop::Compiler::Metagrammar)

    # File lib/treetop/compiler/metagrammar.rb, line 2492
          def _nt_node_class_expression
            start_index = index
            if node_cache[:node_class_expression].has_key?(index)
              cached = node_cache[:node_class_expression][index]
              @index = cached.interval.end if cached
              return cached
            end

            i0 = index
            i1, s1 = index, []
            r2 = _nt_space
            s1 << r2
            if r2
              if input.index('<', index) == index
                r3 = instantiate_node(SyntaxNode,input, index...(index + 1))
                @index += 1
              else
                terminal_parse_failure('<')
                r3 = nil
              end
              s1 << r3
              if r3
                s4, i4 = [], index
                loop do
                  i5, s5 = index, []
                  i6 = index
                  if input.index('>', index) == index
                    r7 = instantiate_node(SyntaxNode,input, index...(index + 1))
                    @index += 1
                  else
                    terminal_parse_failure('>')
                    r7 = nil
                  end
                  if r7
                    r6 = nil
                  else
                    self.index = i6
                    r6 = instantiate_node(SyntaxNode,input, index...index)
                  end
                  s5 << r6
                  if r6
                    if index < input_length
                      r8 = instantiate_node(SyntaxNode,input, index...(index + 1))
                      @index += 1
                    else
                      terminal_parse_failure("any character")
                      r8 = nil
                    end
                    s5 << r8
                  end
                  if s5.last
                    r5 = instantiate_node(SyntaxNode,input, i5...index, s5)
                    r5.extend(NodeClassExpression0)
                  else
                    self.index = i5
                    r5 = nil
                  end
                  if r5
                    s4 << r5
                  else
                    break
                  end
                end
                if s4.empty?
                  self.index = i4
                  r4 = nil
                else
                  r4 = instantiate_node(SyntaxNode,input, i4...index, s4)
                end
                s1 << r4
                if r4
                  if input.index('>', index) == index
                    r9 = instantiate_node(SyntaxNode,input, index...(index + 1))
                    @index += 1
                  else
                    terminal_parse_failure('>')
                    r9 = nil
                  end
                  s1 << r9
                end
              end
            end
            if s1.last
              r1 = instantiate_node(SyntaxNode,input, i1...index, s1)
              r1.extend(NodeClassExpression1)
              r1.extend(NodeClassExpression2)
            else
              self.index = i1
              r1 = nil
            end
            if r1
              r0 = r1
            else
              if input.index('', index) == index
                r10 = instantiate_node(SyntaxNode,input, index...(index + 0))
                r10.extend(NodeClassExpression3)
                @index += 0
              else
                terminal_parse_failure('')
                r10 = nil
              end
              if r10
                r0 = r10
              else
                self.index = i0
                r0 = nil
              end
            end

            node_cache[:node_class_expression][start_index] = r0

            return r0
          end