original_string: public function start(string $key)
      {
          $filteredKey = $this->filterKey($key);
          $value = $this->get($filteredKey);
          if ($value === null) {
              $this->lastKey = $filteredKey;
              ob_start();
          } else {
              $this->lastKey = null;
              trigger_error('Cache start failed');
          }
          return $this;
      }
code: public function start(string $key)
      {
          $filteredKey = $this->filterKey($key);
          $value = $this->get($filteredKey);
          if ($value === null) {
              $this->lastKey = $filteredKey;
              ob_start();
          } else {
              $this->lastKey = null;
              trigger_error('Cache start failed');
          }
          return $this;
      }
code_tokens: public function start ( string $ key ) { $ filteredKey = $ this -> filterKey ( $ key ) ; $ value = $ this -> get ( $ filteredKey ) ; if ( $ value === null ) { $ this -> lastKey = $ filteredKey ; ob_start ( ) ; } else { $ this -> lastKey = null ; trigger_error ( 'Cache start failed' ) ; } return $ this ; }
docstring: Start cache via buffer
  @param string $key
  @return $this
docstring_tokens: Start cache via buffer