{
  # lcase/ucase data expression
  # empty configs are not accepted by Kea
  "Dhcp4": {
    "valid-lifetime": 1800,
    "client-classes": [
      # reduce literals
      {
        "name": "literal",
        /// from: match if (option dhcp.host-name) = (concat(uppercase('www.'), concat('example.', lowercase('COM'))))
        "test": "option[12].hex == 'WWW.example.com'"
      }
    ]
  }
}