I don’t think Haskell programmers ridicule Java unless they are responding to people trying to ridicule Haskell. It’s one thing to be ridiculed by a person who knows both languages. But in a majority of cases attacks on Haskell come from the position of ignorance. Java programmers and C++ programmers often repeat old cliches about functional programming, like: you cannot program without mutation; I/O is impossible; or that, in the real world, everything is changeable.

I do criticize C++ and contrast it with Haskell, because I programmed in C++ for longer than I care to admit and I can see its shortcomings. As Bjarne Stroustrup once said, “Within C++, there is a much smaller and cleaner language struggling to get out.” I say, that language is Haskell.

C++ programmers criticize C++. The designers of the language criticize C++. But I never felt superior because I learned Haskell. They can learn Haskell too. And there are C++ programmers who can do amazing things with the language.

Haskell, Java, and C++, they all serve different purposes. To simplify things: you use C++ for low-level performance, Java for its ease of learning, and Haskell for program verification, composability, and concurrency.