@Test
    public final void basicUse() {
        assertSame(_11, instance.first);
        assertSame(_12, instance.second);
    }
Test case used for testing and experimenting with the tuple APIs. It seems
Tuple4 is just as horrible as I first assumed, but using quick-fix funtions
in the IDE made writing the code less painful than I guessed..

@author <a href="mailto:steinar@yahoo-inc.com">Steinar Knutsen</a>
vespajlib/src/test/java/com/yahoo/collections/TupleTestCase.java