es-toolkit
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A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.
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TypeScript
//#region src/fp/array/last.d.ts
/**
* Creates a function that returns the last element of a non-empty array.
*
* This overload preserves the non-empty tuple guarantee: the returned function
* always returns T when the piped array has at least one element.
*
* @template T - The type of elements in the array.
* @returns A function that maps a non-empty readonly array to its last element.
*
* @example
* import { last, pipe } from 'es-toolkit/fp';
*
* pipe([1, 2, 3] as const, last());
* // => 3
*/
declare function last<T>(): (array: readonly [...T[], T]) => T;
/**
* Creates a function that returns the last element of an array, or undefined.
*
* Empty arrays return undefined, matching the main {@link last} behavior. Use
* the returned function with {@link pipe}.
*
* @template T - The type of elements in the array.
* @returns A function that maps a readonly array to its last element, or undefined.
*
* @example
* import { last, pipe } from 'es-toolkit/fp';
*
* pipe([] as number[], last());
* // => undefined
*/
declare function last<T>(): (array: readonly T[]) => T | undefined;
//#endregion
export { last };