code: func UnmarshalValues(data string) (first, second string, err error) {
  	// Find the delimiter.
  	pos := strings.Index(data, delimiter)
  	if pos < 0 {
  		err = fmt.Errorf("unmarshal values: no delimiter found: '%s'", data)
  		return
  	}
  
  	// Extract the value length integer of the first value.
  	l, err := strconv.Atoi(data[:pos])
  	if err != nil {
  		err = fmt.Errorf("invalid value length: '%s'", data[:pos])
  		return
  	}
  
  	// Remove the value length from the data string.
  	data = data[pos+1:]
  
  	// Validate the value length.
  	if l < 0 || l > len(data) {
  		err = fmt.Errorf("invalid value length: out of bounds: '%v'", l)
  		return
  	}
  
  	// Split the first value from the second.
  	first = data[:l]
  	second = data[l:]
  
  	return
  }
docs: // UnmarshalValues splits two values from a single string.
  // This function is chainable to extract multiple values.