He’s a Haskell purist and (for lack of a better word) religious about it. He’s written what he thinks is the only good book in what he thinks is the only good language, so that tells you a lot about how he thinks. He views the world with a very rigorous set of particulars around what is “good” and what is “bad,” and because others don’t agree with those very specific particulars he considers everything else “bad” or “lazy.”

I like Chris, and he’s clearly a smart guy, but he’s not a person that pedagogical lessons should be learned from.

The book he wrote is a good example - and I enjoyed the book and recommend it. But it’s full of him using big words because at times he can, almost showing off, not because he should. I liked the book, and am glad he teaches the fundamentals of the lambda calculus, but it is very particular to Chris’s style, and that makes it the best programming book written in his eyes, despite not being the “best” programming book objectively.

> He’s also written what he thinks is the only good book in what he thinks is the only good language

I've no idea whether he thinks it's the only good Haskell book (do you have a reference for him claiming that?) but there is a sizeable segment of the Haskell community that considers it the best Haskell book. (I've never read it, personally.)

It pretty clearly, in my mind, is the best Haskell book. There are really only a couple attempts ever made at writing a Haskell book, so there’s not too terribly much competition.

There are many Haskell books. I bought and read a couple dozen for HPFFP, there are more than that but many aren't meant to be end-to-end introductions to Haskell.

It would be surprising if it were otherwise given its origins and age.