# File lib/treetop/compiler/metagrammar.rb, line 3053
      def _nt_alpha_char
        start_index = index
        if node_cache[:alpha_char].has_key?(index)
          cached = node_cache[:alpha_char][index]
          @index = cached.interval.end if cached
          return cached
        end

        if has_terminal?('\G[A-Za-z_]', true, index)
          next_character = index + input[index..-1].match(/\A(.)/um).end(1)
          r0 = instantiate_node(SyntaxNode, input, index...next_character)
          @index = next_character
        else
          r0 = nil
        end

        node_cache[:alpha_char][start_index] = r0

        r0
      end