findIndex

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

Returns the index of the first element in array that satisfies the provided predicate function, or -1 if no element is found.

Example

data-first

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

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

data-last

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

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