heads.json

{
  "head_names": [
    "op",
    "unit",
    "which",
    "dow",
    "ord",
    "field",
    "has_at"
  ],
  "heads": {
    "op": [
      "none",
      "on",
      "named",
      "since",
      "until",
      "time_of_day",
      "between",
      "last_n",
      "next_n",
      "this",
      "last",
      "next",
      "weekend",
      "dow",
      "nth_weekday",
      "every"
    ],
    "unit": [
      "na",
      "minute",
      "hour",
      "day",
      "week",
      "month",
      "quarter",
      "year"
    ],
    "which": [
      "na",
      "this",
      "last",
      "next"
    ],
    "dow": [
      "na",
      "mon",
      "tue",
      "wed",
      "thu",
      "fri",
      "sat",
      "sun"
    ],
    "ord": [
      "na",
      "1",
      "2",
      "3",
      "4",
      "5",
      "last"
    ],
    "field": [
      "na",
      "weekday",
      "weekend",
      "day",
      "mon",
      "tue",
      "wed",
      "thu",
      "fri",
      "sat",
      "sun"
    ],
    "has_at": [
      "0",
      "1"
    ]
  }
}