reactor-core/src/main/java/reactor/util/function/Tuples.java
public static <T1, T2, T3, T4, R> Function<Object[], R> fn4(final Function<Tuple4<T1, T2, T3, T4>, R> delegate) {
		return objects -> delegate.apply(Tuples.<T1, T2, T3, T4>fn4().apply(objects));
	}
public static <T1, T2, T3, T4, R> Function<Object[], R> fn4(final Function<Tuple4<T1, T2, T3, T4>, R> delegate) {
		return objects -> delegate.apply(Tuples.<T1, T2, T3, T4>fn4().apply(objects));
	}
A converting function from Object array to {@link Tuple4} to R.

@param <T1> The type of the first value.
@param <T2> The type of the second value.
@param <T3> The type of the third value.
@param <T4> The type of the fourth value.
@param <R> The type of the return value.
@param delegate the function to delegate to

@return The unchecked conversion function to R.