MathPHP\SetTheory\Set::addMulti PHP Method

    public function addMulti(array $members) : Set
    {
        foreach ($members as $member) {
            $this->A[$this->getKey($member)] = $member;
        }
        return $this;
    }

 /**
  * @dataProvider dataProviderForAddMulti
  */
 public function testAddMulti(array $A, array $x, array $R)
 {
     $setA = new Set($A);
     $setR = new Set($R);
     $setA->addMulti($x);
     $this->assertEquals($setR, $setA);
     $this->assertEquals($setR->asArray(), $setA->asArray());
 }