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

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

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

    This helper is specific to es-toolkit/fp. Use it when you want this operation as part of a pipe pipeline.

    Usage

    length returns the number of values in the piped array.

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

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

    Parameters

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

    Returns

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

    (array: readonly T[]) => number
    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.