array.aggregate()

This method operates on an array. You typically fetch documents from a collection as a set, not an Array. For the equivalent Set method, see set instance methods.

For differences between Sets and Arrays, see Sets vs. Arrays.

Aggregate all elements of an Array.

Signature

aggregate(seed: A, combiner: (A, A) => A) => A

Description

Aggregates all elements of the calling Array. There is no ordering expectation.

The calling Array isn’t changed.

Parameters

Parameter Type Required Description

seed

Generic

true

Initial state value.

combiner

Function

true

Anonymous FQL function that aggregates the elements.

Combiner function parameters:

Parameter Type Required Description

accumulator

Generic

Value returned by the previous invocation.

current

Generic

The current element’s value.

Return value

Type Description

Generic

Aggregate of the iterable. If the iterable is empty, the seed value is returned.

Examples

let iter = [1, 2, 3, 4]
iter.aggregate(0, (a, b) => a + b)
10
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