code: func (d *DotGit) processLine(line string) (*plumbing.Reference, error) {
  	if len(line) == 0 {
  		return nil, nil
  	}
  
  	switch line[0] {
  	case '#': // comment - ignore
  		return nil, nil
  	case '^': // annotated tag commit of the previous line - ignore
  		return nil, nil
  	default:
  		ws := strings.Split(line, " ") // hash then ref
  		if len(ws) != 2 {
  			return nil, ErrPackedRefsBadFormat
  		}
  
  		return plumbing.NewReferenceFromStrings(ws[1], ws[0]), nil
  	}
  }
docs: // process lines from a packed-refs file