iterable-iterator/cardinality

/**
 * Eq.
 *
 * @param {number} n
 * @param {Iterable} iterable
 */
const eq = (n, iterable) => {
    if (n < 0 || !Number.isInteger(n)) return false;

    if (iterable.length !== undefined) return iterable.length === n;

    if (iterable.size !== undefined) return iterable.size === n;

    const it = iterable[Symbol.iterator]();

    for (; n > 0; --n) if (it.next().done) return false;

    return it.next().done;
};

export default eq;