findLastIndexOrElse

function Array.findLastIndexOrElse<T, U>(
    target: readonly T[],
    predicate: (
        value: NoInfer<T>,
        index: number,
        target: readonly NoInfer<T>[],
    ) => boolean,
    orElse: (target: readonly NoInfer<T>[]) => U,
): number | U

Returns the index of the last element in target that satisfies the provided predicate function. If no element satisfies the predicate, calls orElse with the original array.

Example

data-first

import { Array } from "@monstermann/array";

Array.findLastIndexOrElse(
    [1, 3, 2, 4],
    (x) => x > 2,
    () => -1,
); // 3

Array.findLastIndexOrElse(
    [1, 2, 3, 4],
    (x) => x > 5,
    (arr) => arr.length,
); // 4

data-last

import { Array } from "@monstermann/array";

pipe(
    [1, 3, 2, 4],
    Array.findLastIndexOrElse(
        (x) => x > 2,
        () => -1,
    ),
); // 3

pipe(
    [1, 2, 3, 4],
    Array.findLastIndexOrElse(
        (x) => x > 5,
        (arr) => arr.length,
    ),
); // 4