code: public static <T, U, R> ToDoubleBiFunction<T, U> compose(
          final BiFunction<? super T, ? super U, ? extends R> biFunction, 
          final ToDoubleFunction<? super R> function)
      {
          return (x,y) -> function.applyAsDouble(biFunction.apply(x, y));
      }
docs: Composes the given functions
  
  @param <T> The first argument type
  @param <U> The second argument type
  @param <R> The first result type
  
  @param biFunction The {@link BiFunction}
  @param function The {@link ToDoubleFunction}
  @return The resulting {@link ToDoubleBiFunction}