array-functions.md

Scope

Array filter functions available through the core query engine.

Source of truth: src/packages/core/src/query-engine/functions/array-functions.ts

Function List (19)

Function	Signature	Description	Example
length	length(arrayValue)	Array length.	[1,2,3] | length -> 3
size	size(value)	Size of array/object.	{a:1,b:2} | size -> 2
first	first(arrayValue)	First element.	[10,20] | first -> 10
last	last(arrayValue)	Last element.	[10,20] | last -> 20
nth	nth(arrayValue, index)	Element at index.	["a","b","c"] | nth(1) -> "b"
reverse	reverse(arrayValue)	Reverse array copy.	[1,2,3] | reverse -> [3,2,1]
sort	sort(arrayValue, key?)	Sort values or object list by key.	[{n:2},{n:1}] | sort("n") -> [{n:1},{n:2}]
unique	unique(arrayValue)	Remove duplicates.	[1,1,2] | unique -> [1,2]
flatten	flatten(arrayValue, depth?)	Flatten nested arrays.	[[1],[2]] | flatten -> [1,2]
slice	slice(arrayValue, start, end?)	Array slice.	[1,2,3,4] | slice(1,3) -> [2,3]
concat	concat(arrayValue, ...arrays)	Concatenate one or more arrays.	[1,2] | concat([3,4], [5]) -> [1,2,3,4,5]
join	join(arrayValue, separator)	Join to string.	["a","b"] | join("-") -> "a-b"
filter	filter(arrayValue, predicate)	Filter with function or expression.	[1,2,3] | filter("> 1") -> [2,3]
map	map(arrayValue, fn)	Map with function or property key.	[{n:1}] | map("n") -> [1]
find	find(arrayValue, condition)	First matching item.	[1,2,3] | find("> 1") -> 2
includes	includes(arrayValue, item)	Membership check.	[1,2,3] | includes(2) -> true
indexOf	indexOf(arrayValue, item)	Index lookup.	[1,2,3] | indexOf(2) -> 1

| reduce | reduce(arrayValue) | Returns input unchanged. | [1,2,3] \| reduce -> [1,2,3] | | where | where(arrayValue, key) | Keep entries with truthy key. | [{a:true},{a:false}] \| where("a") -> [{a:true}] |

Notes

• Expression forms in filter and find support simple scalar and field comparisons.
• sort and reverse return a copied array and do not mutate input.
• where is a convenience alias for truthy-key filtering.
• reduce currently does not accept a reducer callback and is documented to match the current implementation behavior.