You know, this almost reminds me of the ML vs. Haskell debate. I remember fondly, hearing the 15-312 kids talk about how ML is right and everything else is wrong. The CMU PL dept was kind of adorable that way.

One of the classic examples is Haskell's typeclasses. Haskell's typeclasses are kinda kludgy because there's no way to provide more than one instance of a typeclass. ML's functors are way better.

But as it turns out, most of the time, we just need one instance. It's much simpler to invoke, and much easier to understand. If you need more than one instance, then use newtype.

In the end, we wouldn't be where we are in PL without the crazy folks at CMU and Bell labs. So I feel no small amount of sadness that ML didn't win. I concede the notion that ML may have made better design choices. But what matters more to me is that elements of FP get into the mainstream. Here, Haskell has done a better job of showing what is good with FP.