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

    Creates a function that returns the first value of an array. Use it with pipe.

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

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

    Usage

    head returns the first value in the piped array. If the array is empty, it returns undefined.

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

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

pipe([], head()); // => undefined

    Parameters

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

    Returns

    A function that maps a readonly T[] to its first value.

    (array: readonly T[]) => T | undefined
    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.