Comment by pliftkl

Personally, I've written zero lines of production Haskell code, and expect that this will still be true when I retire. Despite that, learning Haskell was probably one of the best things that I've ever done. The learning process sent me down lots of interesting rabbit holes of language design, and certainly made me a more disciplined developer in other languages. The lambda calculus and predicate logic discussed in this article was one of the enjoyable rabbit hole trips induced by Haskell, but it was only one of many.