# File lib/cucumber/parser/feature.rb, line 509
      def _nt_background
        start_index = index
        if node_cache[:background].has_key?(index)
          cached = node_cache[:background][index]
          @index = cached.interval.end if cached
          return cached
        end

        i0, s0 = index, []
        r1 = _nt_comment
        s0 << r1
        if r1
          r2 = _nt_white
          s0 << r2
          if r2
            r3 = _nt_background_keyword
            s0 << r3
            if r3
              s4, i4 = [], index
              loop do
                r5 = _nt_space
                if r5
                  s4 << r5
                else
                  break
                end
              end
              r4 = instantiate_node(SyntaxNode,input, i4...index, s4)
              s0 << r4
              if r4
                r7 = _nt_lines_to_keyword
                if r7
                  r6 = r7
                else
                  r6 = instantiate_node(SyntaxNode,input, index...index)
                end
                s0 << r6
                if r6
                  i8 = index
                  s9, i9 = [], index
                  loop do
                    r10 = _nt_eol
                    if r10
                      s9 << r10
                    else
                      break
                    end
                  end
                  if s9.empty?
                    @index = i9
                    r9 = nil
                  else
                    r9 = instantiate_node(SyntaxNode,input, i9...index, s9)
                  end
                  if r9
                    r8 = r9
                  else
                    r11 = _nt_eof
                    if r11
                      r8 = r11
                    else
                      @index = i8
                      r8 = nil
                    end
                  end
                  s0 << r8
                  if r8
                    r12 = _nt_steps
                    s0 << r12
                  end
                end
              end
            end
          end
        end
        if s0.last
          r0 = instantiate_node(SyntaxNode,input, i0...index, s0)
          r0.extend(Background0)
          r0.extend(Background1)
        else
          @index = i0
          r0 = nil
        end

        node_cache[:background][start_index] = r0

        r0
      end