@Test
    public void testAppend() {
        assertEquals(asList(1, 2, 3, 4), Seq.of(1).append(Seq.of(2, 3, 4)).toList());
        assertEquals(asList(1, 2, 3, 4), Seq.of(1, 2).append(Seq.of(3, 4)).toList());
        assertEquals(asList(1, 2, 3, 4), Seq.of(1).append(2, 3, 4).toList());
        assertEquals(asList(1, 2, 3, 4), Seq.of(1, 2).append(3, 4).toList());
    }
@author Lukas Eder
@author Roman Tkalenko
jOOL/src/test/java/org/jooq/lambda/SeqTest.java