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The Standard Library has been moved to JSR. See the blog post for details.
function findLastIndex
import { findLastIndex } from "https://deno.land/std@0.107.0/collections/find_last_index.ts";

Returns the index of the last element in the given array matching the given predicate

Example:

import { findLastIndex } from "https://deno.land/std@0.107.0/collections/mod.ts";
import { assertEquals } from "https://deno.land/std@0.107.0/testing/asserts.ts";

const numbers = [ 4, 2, 7 ]
const lastIndexNumber = findLastIndex(numbers, it => it % 2 === 0)

assertEquals(lastIndexNumber, 1)

Parameters

array: readonly T[]
predicate: (el: T) => boolean

Returns

number | undefined