@Test
void isBounded() {

    assertThat(Range.of(10L, 20L).isBounded()).isTrue();
    assertThat(Range.from(10L).isBounded()).isFalse();
    assertThat(Range.to(20L).isBounded()).isFalse();
    assertThat(new Range<Long>().isBounded()).isFalse();
}