code: func stringFromMixedArray(parts []interface{}) string {
  	var buf bytes.Buffer
  	for _, part := range parts {
  		if s, ok := part.(string); ok {
  			buf.WriteString(s)
  			continue
  		}
  		if num, ok := part.(float64); ok {
  			buf.WriteByte(byte(num))
  			continue
  		}
  	}
  	return buf.String()
  }
docs: // stringFromMixedArray joins a slice of either strings or float64
  // values (as retrieved from JSON decoding) into a string.  These are
  // used for non-UTF8 filenames in "fileNameBytes" fields.  The strings
  // are UTF-8 segments and the float64s (actually uint8 values) are
  // byte values.