ix/src/iterable/every.ts

The Interactive Extensions for JavaScript

import { FindOptions } from './findoptions.js';

/**
 * Determines whether all elements of an iterable sequence satisfy a condition.
 *
 * @template T The type of the elements in the source sequence.
 * @param {Iterable<T>} source An iterable sequence whose elements to apply the predicate to.
 * @param {FindOptions<T>} options The options for a predicate for filtering, thisArg for binding and AbortSignal for cancellation.
 * @returns {boolean} A boolean determining whether all elements in the source sequence pass the test in the specified predicate.
 */
export function every<T>(source: Iterable<T>, options: FindOptions<T>): boolean {
  const { ['thisArg']: thisArg, ['predicate']: predicate } = options;
  let i = 0;
  for (const item of source) {
    if (!predicate.call(thisArg, item, i++)) {
      return false;
    }
  }
  return true;
}