code: func createOutputWrapper(uri string, classes []LogClass) (*loggerOutputWrapper, error) {
  	// If the caller didn't give us any classes to configure then we do
  	// nothing. This can be either an error or not, and since it is just as easy
  	// either way we define this as being a no op rather than error condition.
  	if len(classes) == 0 {
  		return nil, nil
  	}
  
  	// Combine the output classes into just one
  	class := NONE
  	for _, c := range classes {
  		class |= c
  	}
  
  	return createOutputWrapperForClass(uri, class)
  }
docs: // createOutputWrapper generates a new loggerOutputWrapper based on the passed
  // parameters. It will return an error if it fails to generate the output. It
  // will return nil, nil if there are no classes specified.