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/uniq.md.
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    uniq (Functional Programming) es-toolkit

    Creates a function that removes duplicate values from an array. Use it with pipe.

    const result = pipe(array, uniq());
    Info

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

    Usage

    uniq returns a new array containing only unique values, preserving the order of first occurrence. Equality follows SameValueZero (the semantics of Set).

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

pipe([1, 2, 2, 3, 3, 3], uniq()); // => [1, 2, 3]

// Order of first occurrence is preserved.
pipe([3, 1, 2, 1, 3], uniq()); // => [3, 1, 2]

    Parameters

    This function takes no arguments; call it as uniq().

    Returns

    A function that maps a readonly T[] to a new, duplicate-free T[].

    (array: readonly T[]) => 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.