For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt, and this page is available as Markdown at /reference/fp/partition.md.
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    partition (Functional Programming) es-toolkit

    Creates a function that splits values into passing and failing groups. Use it with pipe.

    const result = pipe(array, partition(predicate));
    Info

    Prefer the original es-toolkit partition in ordinary code. Use this fp variant when composing transformations with pipe.

    Usage

    partition returns a pair of arrays. The first array contains values for which predicate returns true, and the second contains the rest.

    import { partition, pipe } from 'es-toolkit/fp';

pipe(
  [1, 2, 3, 4],
  partition(value => value % 2 === 0)
); // => [[2, 4], [1, 3]]

    Parameters

    predicate(value: T) => booleanrequired

    The function that decides which group each value belongs to.

    Returns

    A function that maps a readonly T[] to passing and failing arrays.

    (array: readonly T[]) => [truthy: T[], falsy: T[]]
    Source: es-toolkit

    Re-exported verbatim from es-toolkit. Implementation, edge cases, and performance behavior are owned upstream. This page mirrors the documentation at the pinned version; the linked source is authoritative.