@Test
public void plusInteger() {
Function2<Integer, Integer, Integer> plusInteger = Functions2.integerAddition();
Assert.assertEquals(Integer.valueOf(5), plusInteger.value(2, 3));
}
@Test
public void asFunction2Function() {
Function2<Integer, Object, String> block = Functions2.fromFunction(String::valueOf);
Assert.assertEquals("1", block.value(1, null));
}