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$shuffle

$shuffle(array) -> array
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Arrays And Sequences

Source: JSONata

Documentation​

Returns a shuffled copy of the input array.

FUME uses a Fisher-Yates-style shuffle, so the output contains the same members as the input but in an intentionally unpredictable order. undefined input returns undefined, and arrays of length 0 or 1 are returned unchanged.

Because the exact ordering is nondeterministic, examples should assert stable properties of the shuffled result instead of a specific permutation.

Examples​

Shuffle an array without depending on a specific order​

Input

This example uses the patient-summary example input. The expression shuffles the tags array, then sorts the shuffled values only for display so the rendered result stays deterministic.

Example input

JSON
{
  "patientId": "pat-0001",
  "name": {
    "given": "Avery",
    "family": "Reed",
    "display": "Avery Reed"
  },
  "birthDate": "1990-06-12",
  "sex": "female",
  "primaryCareTeam": {
    "organization": "ExampleCare",
    "facility": "ExampleCare Clinic",
    "practitioner": {
      "practitionerId": "prac-4001",
      "display": "Jordan Kim"
    }
  },
  "identifiers": {
    "memberId": "mbr-3001",
    "recordNumber": "rec-5001"
  },
  "tags": [
    "demo",
    "fictional"
  ],
  "_xmlTagName": "patientSummary"
}

Expression

{ "count": $count($shuffle(tags)), "members": $sort($shuffle(tags)) }

Result

{
  "count": 2,
  "members": [
    "demo",
    "fictional"
  ]
}