Two other things that shouldn't be mixed are a programming language's features and what programmers are using them for. As noted in other comments, Haskell is

Two other things that shouldn't be mixed are a programming language's features and what programmers are using them for. As noted in other comments, Haskell is good at defining all sorts of functions, but the card castles of excessive and inappropriate algebraic abstraction are a tradition of rather uniformly extremist Haskell users.