public void FlattenTest()
{
OclOrderedSet level1 = TestUtils.CreateIntOrderedSet(1, 2);
OclOrderedSet level2 = new OclOrderedSet(level1.oclType(), level1, level1);
OclOrderedSet level3 = new OclOrderedSet(level2.oclType(), level2, level2);
TestUtils.AreEqual(TestUtils.CreateIntOrderedSet(1, 2), level1.flatten());
TestUtils.AreEqual(TestUtils.CreateIntOrderedSet(1, 2), level2.flatten());
TestUtils.AreEqual(TestUtils.CreateIntOrderedSet(1, 2), level3.flatten());
}