Comment by lexi-lambda

I have provided a translation of the NonEmpty datatype into Java in this comment: https://news.ycombinator.com/item?id=21478322

However, to answer your “why” question: mostly just because I write Haskell for a living, and my primary personal motivation for writing this blog post was to share with my coworkers and to point to during code reviews. Therefore, it makes the most sense for the examples to be in Haskell! Haskell is also especially well-suited for communicating this sort of thing if you already understand the notation, as you can sort of see from the Java translation: it’s significantly more verbose just to get the same idea across. Still, it’d be great if someone were to provide a “translation” of the same ideas to other languages, no doubt!