/**
* Axiom: A Δ B = (A ∖ B) ∪ (B ∖ A)
* A symmetric different B equals union of A diff B and B diff A
* @dataProvider dataProviderForTwoSets
*/
public function testASymmetricDifferentBEqualsUnionADiffBAndBDiffA(Set $A, Set $B)
{
$AΔB = $A->symmetricDifference($B);
$A∖B = $A->difference($B);
$B∖A = $B->difference($A);
$⟮A∖B⟯∪⟮B∖A⟯ = $A∖B->union($B∖A);
$this->assertEquals($AΔB, $⟮A∖B⟯∪⟮B∖A⟯);
$this->assertEquals($AΔB->asArray(), $⟮A∖B⟯∪⟮B∖A⟯->asArray());
}
