Function is

src/is.ts:57–82

(valueA: unknown, valueB: unknown)

 * and `hashCode()`.
 */
export function is(valueA: unknown, valueB: unknown): boolean {
  if (valueA === valueB || (valueA !== valueA && valueB !== valueB)) {
    return true;
  }
  if (!valueA || !valueB) {
    return false;
  }
  if (
    typeof valueA.valueOf === 'function' &&
    typeof valueB.valueOf === 'function'
  ) {
    valueA = valueA.valueOf();
    valueB = valueB.valueOf();
    if (valueA === valueB || (valueA !== valueA && valueB !== valueB)) {
      return true;
    }
    if (!valueA || !valueB) {
      return false;
    }
  }
  return !!(
    isValueObject(valueA) &&
    isValueObject(valueB) &&
    valueA.equals(valueB)
  );
}