{
  # subclass declaration config
  # options
  "Dhcp4": {
    "option-def": [
      {
        "space": "dhcp4",
        "name": "myversion",
        "code": 251,
        "type": "uint16"
      }
    ],
    "client-classes": [
      # superclass declaration
      /// match: hardware
      {
        "name": "foobar",
        "option-data": [
          {
            "space": "dhcp4",
            "name": "myversion",
            "code": 251,
            "data": "1"
          }
        ]
      },
      # simple subclass declaration
      /// subclass selector 0x0x0100070e364819
      {
        "name": "sub#foobar#0",
        "option-data": [
          {
            "space": "dhcp4",
            "name": "myversion",
            "code": 251,
            "data": "1"
          }
        ],
        /// from: match hardware
        /// data: 0x0100070e364819
        "test": "concat(substring(pkt4.htype,-1,all), pkt4.mac) == 0x0100070e364819"
      },
      # option setting subclass declaration
      /// subclass selector 0x0x01000bfd32e6fa
      {
        "name": "sub#foobar#1",
        "option-data": [
          {
            "space": "dhcp4",
            "name": "myversion",
            "code": 251,
            "data": "2"
          }
        ],
        /// from: match hardware
        /// data: 0x01000bfd32e6fa
        "test": "concat(substring(pkt4.htype,-1,all), pkt4.mac) == 0x01000bfd32e6fa"
      }
    ]
  }
}