//all

//all will only accept values accepted by every schema given in a list.

Match integers between 3 and 18:

{
  "type": "//all",
  "of": [
    { "type": "//num", "range": { "min-ex": 0, "max": 18 } },
    { "type": "//num", "range": { "min": 3 } },
    "//int",
  ]
}

/.meta/all, the schema for //all definitions:

{
  "type": "//rec",
  "required": {
    "type": { "type": "//str", "value": "//all" },
    "of":   {
      "type": "//arr",
      "contents": "/.meta/schema",
      "length": { "min": 1 }
    }
  }
}