Why Isn't Functional Programming the Norm? [video]

As someone who writes pure FP for a living at a rather large and well known org, these threads physically hurt me. They're consistently full of bad takes from people who don't like FP, or haven't written a lick of it. Subsequently, you get judgements that are chock full of misconceptions of what FP actually is, and the pros and cons outsiders believe about FP are completely different from its practitioners. It's always some whinge about FP not mapping "to the metal", which is comical given say, Rust's derivation from what is quite functional stock.

My personal belief? We just don't teach it. Unis these days start with Python, so a lot of student's first exposure to programming is a multi-paradigm language that can't really support the higher forms of FP techniques. Sure, there may be a course that covers Haskell or a Lisp, but the majority of the teaching is conducted in C, C++, Java or Python. Grads come out with a 4 year headstart on a non-FP paradigm, why would orgs use languages and techniques that they're going to have to train new grads with from scratch?

And training people in FP is bloody time consuming. I've recorded up to 5 hours of lecture content for devs internally teaching functional Scala, which took quadruple the time to write and revise, plus the many hours in 1-on-1 contact teaching Scala and Haskell. Not a lot of people have dealt with these concepts before, and you really have to start from scratch.

I don't agree the lack of proactive education is the reason FP isn't the norm. Your conclusion doesn't take into account the counterfactuals:

- C Language took off in popularity despite BASIC/Pascal being the language more often taught in schools

- languages like PHP/Javascript/Python/Java all became popular even though prestigious schools like MIT were teaching Scheme/Lisp (before switching to Python in 2009).

You don't need school curricula to evangelize programming paradigms because history shows they weren't necessarily the trendsetters anyway.

On a related note, consider that programmers are using Git DVCS even though universities don't have formal classes on Git or distributed-version-control. How would Git's usage spread with everybody adopting it be possible if universities aren't teaching it? Indeed, new college grads often lament that schools didn't teach them real-world coding practices such as git commands.

Why does Functional Programming in particular need to be taught in schools for it to become a norm but all the other various programming topics do not?

Because I think it is harder for people who have programmed with other paradigms - following an inverse law, most things should get easier to learn with experience, not harder. It's foreign, it's weird, it's back to front. It doesn't have an immediately obvious benefit to what people are used to, and the benefits it has come at scale and up against the wall of complexity (in my opinion). It's hard to adopt upfront. At the small scale it's often painful to use. The syntax is weird. It's aggressively polymorphic, reasoning in abstractions rather than concretions. I could go on (and yet I still adore it).

The only reason FP has been successful as it is, is because its evangelists are incredibly vocal, to the point of being fucking annoying sometimes. It's had to be forced down people's throats at times, and frankly, there's no better place to force a paradigm down someone's throats than at a university, where non-compliance comes at academic penalty, and when the mind is most impressionable.

That's also a great way to make people hate it. An example is literature classes with mandatory reading and how they make students hate reading fiction.

I would also say that this might turn off more students from programming. We had functional programming in uni, where we learned Haskell. Maybe a handful of students liked it or were neutral about it, the vast majority seemed to have a negative view of it.

I think that FP is just more difficult to learn. Just look at essentially any entry level programming course and how people understand loops vs recursion.

What do you do?

If FP is not mandatory at Google-scale, it isn’t mandatory at your scale.

The kind of problems that emerge at scale are not the kind of problems FP tackles.