Phpml\Math\Set::removeAll PHP Метод

    public function removeAll(array $elements) : Set
    {
        $this->elements = self::sanitize(array_diff($this->elements, $elements));
        return $this;
    }

 public function testEmpty()
 {
     $set = new Set([1, 2]);
     $set->removeAll([2, 1]);
     $this->assertEquals(new Set(), $set);
     $this->assertTrue($set->isEmpty());
 }