Ask HN: Which functional programming language is the popular enterprise choice?

I would "bet the whole farm" on Haskell before Scala.

That's not to make a dig at Scala. It's way better than Java. It's also really complicated, and the need for JVM compatibility is a big part of that. Then you have the compile speed issues, the problematic tool chain, and the fact that average Java programmers, given Scala, will create unmaintainable nightmares.

I'd use Scala over Haskell when I wanted JVM interoperability, or if I needed to train people up quickly. For a "bet the whole farm" play, existing programmer familiarity actually matters a bit less-- "the whole farm" is rarely bet on a one-month project-- and I'd pick Haskell first.

I think that it's self-reinforcing.

Let's have an honest conversation. Haskell is a great programming language. It might be the best. It is not going to get more than a 20% market share in the programming community. It could get 1 percent, which is about 5 times what it has now (measured in available jobs) and 25 times what it had 5 years ago. It could get 5 percent. It might even get 15 percent.

Much of our industry is based on trend-chasing. This 25-year-old language that happens to be really good, but whose strongest proponents even admit that it will never have a dominant (25+ percent) market share like Java or Javascript or PHP, is not a shoo-in for "next dominant paradigm".

Functional programming may be the next important paradigm and we're seeing the best programmers and the most important work gravitate toward it, but it's never going to be the go-to tool for the business-driven Scrum engineering that seems to dominate the mainstream of software.

Scala, Clojure, and Erlang come to mind. F# is another possibility, since .NET/CLR is becoming increasingly popular in the enterprise (particularly in Windows-heavy datacenters), though I don't know of a whole lot of enterprise F# deployments off the top of my head.

Erlang's a bit of a special case; while you probably won't see many enterprises consciously using it (unless they use Jabber/XMPP via ejabberd, of course), it's rather abundant behind-the-scenes with communication infrastructure, and multiple large telecom providers and OEMs (including - obviously - Ericsson) use it for their equipment and infrastructure.

Scala is not a functional programming language, it is OO first and foremost. It has better support for functional programming than Java 8, Python or Smalltalk. And that in itself is great.

The language is more restrictive and sometimes it's harder to get something working. Of course the payoff is immense, you end up with much more maintainable and composable code. However I'm not convinced that many enterprises care much about these properties, as they are often more of a long term win. People also have an emotional attachment to their existing tools and paradigms.