code: public final void mT__21() throws RecognitionException {
          try {
              int _type = T__21;
              int _channel = DEFAULT_TOKEN_CHANNEL;
              // InternalXtext.g:21:7: ( '@' )
              // InternalXtext.g:21:9: '@'
              {
              match('@'); 
  
              }
  
              state.type = _type;
              state.channel = _channel;
          }
          finally {
          }
      }
docs: $ANTLR start "T__21"