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/find.d.ts
/**
* Creates a function that returns the first value accepted by a type guard.
*
* The predicate receives the value, index, and full input array. The returned
* function returns undefined when no value matches.
*
* @template T - The type of elements in the array.
* @template S - The narrowed element type accepted by the type guard.
* @param predicate - Type guard called with each value, index, and array until it returns true.
* @returns A function that maps a readonly array to the first matching value, or undefined.
*
* @example
* import { find, pipe } from 'es-toolkit/fp';
*
* const isString = (value: string | number): value is string => typeof value === 'string';
* pipe([1, 'a', 2], find(isString));
* // => 'a'
*/
declare function find<T, S extends T>(predicate: (value: T, index: number, array: readonly T[]) => value is S): (array: readonly T[]) => S | undefined;
/**
* Creates a function that returns the first value matching a predicate.
*
* The predicate receives the value, index, and full input array. The returned
* function returns undefined when no value matches.
*
* @template T - The type of elements in the array.
* @param predicate - Predicate called with each value, index, and array until it returns true.
* @returns A function that maps a readonly array to the first matching value, or undefined.
*
* @example
* import { find, pipe } from 'es-toolkit/fp';
*
* pipe([{ id: 1 }, { id: 2 }], find(item => item.id === 2));
* // => { id: 2 }
*/
declare function find<T>(predicate: (value: T, index: number, array: readonly T[]) => boolean): (array: readonly T[]) => T | undefined;
//#endregion
export { find };