# File lib/treetop/compiler/metagrammar.rb, line 1901
      def _nt_nonterminal
        start_index = index
        if node_cache[:nonterminal].has_key?(index)
          cached = node_cache[:nonterminal][index]
          @index = cached.interval.end if cached
          return cached
        end

        i0, s0 = index, []
        i1 = index
        r2 = _nt_keyword_inside_grammar
        if r2
          r1 = nil
        else
          self.index = i1
          r1 = instantiate_node(SyntaxNode,input, index...index)
        end
        s0 << r1
        if r1
          i3, s3 = index, []
          r4 = _nt_alpha_char
          s3 << r4
          if r4
            s5, i5 = [], index
            loop do
              r6 = _nt_alphanumeric_char
              if r6
                s5 << r6
              else
                break
              end
            end
            r5 = instantiate_node(SyntaxNode,input, i5...index, s5)
            s3 << r5
          end
          if s3.last
            r3 = instantiate_node(SyntaxNode,input, i3...index, s3)
            r3.extend(Nonterminal0)
          else
            self.index = i3
            r3 = nil
          end
          s0 << r3
        end
        if s0.last
          r0 = instantiate_node(Nonterminal,input, i0...index, s0)
          r0.extend(Nonterminal1)
        else
          self.index = i0
          r0 = nil
        end

        node_cache[:nonterminal][start_index] = r0

        return r0
      end