original_string: private function _checkConfig($config = null)
      {
          if ($config === null) {
              $config = $this->config;
          }
          if (!($config instanceof ArrayAccess)
              && !is_array($config)
          ) {
              throw new Klarna_IncompleteConfigurationException;
          }
      }
code: private function _checkConfig($config = null)
      {
          if ($config === null) {
              $config = $this->config;
          }
          if (!($config instanceof ArrayAccess)
              && !is_array($config)
          ) {
              throw new Klarna_IncompleteConfigurationException;
          }
      }
code_tokens: private function _checkConfig ( $ config = null ) { if ( $ config === null ) { $ config = $ this -> config ; } if ( ! ( $ config instanceof ArrayAccess ) && ! is_array ( $ config ) ) { throw new Klarna_IncompleteConfigurationException ; } }
docstring: Ensure the configuration is of the correct type.
  
  @param array|ArrayAccess|null $config an optional config to validate
  
  @return void
docstring_tokens: Ensure the configuration is of the correct type .