sort_by

Description

Sort an array using an expression expr as the sort key. For each element in the array of elements, the expr expression is applied and the resulting value is used as the key used when sorting the elements.

If the result of evaluating the expr against the current array element results in type other than a number or a string, an invalid-type error will occur.

Below are several examples using the people array (defined above) as the given input. sort_by follows the same sorting logic as the sort function.

Arguments

Required

Name	Type	Description
elements	array
expr	expression->number, expression->string

Returns

Type: array

Examples

search(sort_by(people, &age), {"people":[{"age":10,"order":"1"},{"age":10,"order":"2"},{"age":10,"order":"3"},{"age":10,"order":"4"},{"age":10,"order":"5"},{"age":10,"order":"6"},{"age":10,"order":"7"},{"age":10,"order":"8"},{"age":10,"order":"9"},{"age":10,"order":"10"},{"age":10,"order":"11"}]}) → [{"age":10,"order":"1"},{"age":10,"order":"2"},{"age":10,"order":"3"},{"age":10,"order":"4"},{"age":10,"order":"5"},{"age":10,"order":"6"},{"age":10,"order":"7"},{"age":10,"order":"8"},{"age":10,"order":"9"},{"age":10,"order":"10"},{"age":10,"order":"11"}]

Given the following JSON input:

{
  "people": [
    {
      "age": 20,
      "age_str": "20",
      "bool": true,
      "name": "a",
      "extra": "foo"
    },
    {
      "age": 40,
      "age_str": "40",
      "bool": false,
      "name": "b",
      "extra": "bar"
    },
    {
      "age": 30,
      "age_str": "30",
      "bool": true,
      "name": "c"
    },
    {
      "age": 50,
      "age_str": "50",
      "bool": false,
      "name": "d"
    },
    {
      "age": 10,
      "age_str": "10",
      "bool": true,
      "name": 3
    }
  ],
  "empty_list": []
}

Expression	Result
sort_by(people, &age)	[{"age":10,"age_str":"10","bool":true,"name":3},{"age":20,"age_str":"20","bool":true,"name":"a","extra":"foo"},{"age":30,"age_str":"30","bool":true,"name":"c"},{"age":40,"age_str":"40","bool":false,"name":"b","extra":"bar"},{"age":50,"age_str":"50","bool":false,"name":"d"}]
sort_by(people, &age_str)	[{"age":10,"age_str":"10","bool":true,"name":3},{"age":20,"age_str":"20","bool":true,"name":"a","extra":"foo"},{"age":30,"age_str":"30","bool":true,"name":"c"},{"age":40,"age_str":"40","bool":false,"name":"b","extra":"bar"},{"age":50,"age_str":"50","bool":false,"name":"d"}]
sort_by(people, &to_number(age_str))	[{"age":10,"age_str":"10","bool":true,"name":3},{"age":20,"age_str":"20","bool":true,"name":"a","extra":"foo"},{"age":30,"age_str":"30","bool":true,"name":"c"},{"age":40,"age_str":"40","bool":false,"name":"b","extra":"bar"},{"age":50,"age_str":"50","bool":false,"name":"d"}]
sort_by(people, &extra)	ERROR: invalid-type
sort_by(people, &bool)	ERROR: invalid-type
sort_by(people, &name)	ERROR: invalid-type
sort_by(people, name)	ERROR: invalid-type
sort_by(empty_list, &age)	[]