some (for Iterators)

Creates a function that reports whether any element of an iterator matches a predicate. Use it with pipe.

const result = pipe(source, some(predicate));

::: info

In ordinary code, prefer the native Iterator.prototype.some: source.some(predicate). Use this es-toolkit/fp/iterator variant when composing transformations with pipe.

:::

Usage

some(predicate)

some is a terminal step: it consumes the iterator until predicate returns a truthy value and reports whether any element matched. It stops pulling at the first match, so it can complete on an infinite iterator as long as a matching element appears. It delegates to the native Iterator.prototype.some.

import { pipe } from 'es-toolkit/fp';
import { some } from 'es-toolkit/fp/iterator';

// Stops as soon as an even number is found.
pipe(
  [1, 3, 4, 5].values(),
  some(x => x % 2 === 0)
);
// Returns: true

pipe(
  [1, 3, 5].values(),
  some(x => x % 2 === 0)
);
// Returns: false

Parameters

• predicate ((value: T, index: number) => unknown): Called with each element and its index; a truthy return short-circuits to true.

Returns

((source: Iterator<T>) => boolean): A function that consumes an iterator and returns whether any element matched.