In a new post Uncle Bob explains that you shouldn't have to choose between functional programming and object orientation.

In this blog I will make the case that while OO and FP are orthogonal, they are not mutually exclusive. That a good functional program can (and should) be object oriented. And that a good object oriented program can (and should) be functional. But to accomplish this goal we are going to have to define our terms very carefully.

http://blog.cleancoder.com/uncle-bob/2018/04/13/FPvsOO.html