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

    Creates a function that returns sliding windows from an array. Use it with pipe.

    const result = pipe(array, windowed(size, step, options));
    Info

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

    Usage

    windowed returns sub-arrays of length size, moving forward by step each time. Full-window mode is lazy-capable inside pipe.

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

pipe([1, 2, 3, 4], windowed(2)); // => [[1, 2], [2, 3], [3, 4]]

pipe([1, 2, 3, 4], windowed(2, 2)); // => [[1, 2], [3, 4]]

    Parameters

    sizenumberrequired

    The length of each window.

    stepnumber, optionalrequired

    The number of positions to move between windows. Defaults to 1.

    optionsWindowedOptions, optionalrequired

    Options such as whether to include partial trailing windows.

    Returns

    A function that maps a readonly T[] to sliding windows.

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

    Throws

    Throws an error if size or step is not a positive integer.

    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.