Method apply

src/main/java/fieldbox/boxes/Box.java:766–766

(Box b, T1 t, T2 u)

	/**
	 * Marker interface, marks functions as taking a box and something else as a parameter. Allows us to finesse the dispatch of functions stored in properties
	 */
	public interface TriFunctionOfBoxAnd<T1, T2, R> {
		R apply(Box b, T1 t, T2 u);
	}