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    xorBy (Functional Programming) es-toolkit

    Creates a function that returns the symmetric difference by a mapped key. Use it with pipe.

    const result = pipe(array, xorBy(secondArray, mapper));
    Info

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

    Usage

    xorBy compares the values returned by mapper and returns values whose mapped key appears in exactly one array.

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

pipe(
  [{ id: 1 }, { id: 2 }],
  xorBy([{ id: 2 }, { id: 3 }], item => item.id)
); // => [{ id: 1 }, { id: 3 }]

    Parameters

    secondArrayreadonly T[]required

    The array to compare with the piped array.

    mapper(item: T) => Urequired

    The function that returns the comparison key.

    Returns

    A function that maps a readonly T[] to the symmetric difference by key.

    (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.