last
Returns the last element of an array. Used to declaratively write code, rather than writing arr[arr.length - 1]
.
function last<T>(arr: NonEmptyArray<T>): T;
function last<T>(arr: T[]): T | undefined;
- If an array is a normal array (
T[]
),last
returns a nullable value, since it can be empty. - If an array is checked not to be empty by isNonEmptyArray,
last
returns a non-nullable value.
Example
import { isNonEmptyArray } from '@toss/utils';
const array = [1, 2, 3];
last(array); // number | undefined
if (isNonEmptyArray(array)) {
last(array); // number
}