Array Verbs

Array indexing, filtering, sorting, deduplication, and transformation.

Verb	Syntax	Description	Try It
at	`%at @array index`	Get element at index	Try
filter	`%filter @array "condition"`	Filter by condition	Try
flatten	`%flatten @array`	Flatten nested arrays	Try
distinct	`%distinct @array`	Unique values only	Try
sort	`%sort @array`	Sort ascending	Try
sortBy	`%sortBy @array "field"`	Sort by field	Try
reverse	`%reverse @array`	Reverse order	Try
reduce	`%reduce @array "verb" initialValue`	Fold array to single value using named verb	Try
pivot	`%pivot @array "keyField" "valueField"`	Array of objects to object keyed by field	Try
unpivot	`%unpivot @object "keyName" "valueName"`	Object to array of {key, value} objects	Try

Reference

Reduce (reduce) — Fold an Array

Applies a named verb cumulatively to array elements, reducing to a single value.

%reduce @array "verbName" initialValue

The verb must accept 2 arguments (accumulator, current element).
Compatible verbs: add, subtract, multiply, divide, concat, minOf, maxOf, and any custom 2-argument verb.
If the array is empty, returns the initial value.
Null elements are skipped.

Pivot (pivot) — Array to Object

Transforms an array of objects into a single object, using one field as keys and another as values.

%pivot @array "keyField" "valueField"

Each object in the array must have both fields. Objects missing either field are skipped.
If duplicate keys exist, the last value wins.
Key values are coerced to strings.
Returns null if input is not an array.

Example:

Input:  [{"k":"width","v":100}, {"k":"height","v":200}]
Output: {"width": 100, "height": 200}

Unpivot (unpivot) — Object to Array

Transforms an object into an array of {key, value} objects.

%unpivot @object "keyName" "valueName"

Each property of the input object becomes one element in the output array.
Field names in the output are controlled by the keyName and valueName parameters.
Property order follows the original object's key order.
Returns null if input is not an object.

Example:

Input:  {"width": 100, "height": 200}
Output: [{"name":"width","size":100}, {"name":"height","size":200}]

Examples

Array verb examples

second_vehicle = %at @vehicles ##1
active_coverages = %filter @coverages "@.status = 'active'"
unique_states = %distinct @addresses.state
by_premium = %sortBy @coverages "premium"

; Reduce — fold array with a verb
total = %reduce @prices "add" ##0                     ; sum all prices
product = %reduce @factors "multiply" ##1             ; multiply all

; Pivot — array of objects to keyed object
settings = %pivot @configs "key" "value"              ; [{key:"a",value:1}] -> {a:1}

; Unpivot — object to array of {key, value}
rows = %unpivot @dimensions "name" "size"             ; {w:100,h:200} -> [{name:"w",size:100},...]