Why Isn't Functional Programming the Norm? [video] • Hacker News Board

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

#261

Post by Bjartr » Thu, Oct 17, 2019, 9:49 PM UTC

OskarS wrote: post #188

classified wrote: post #178

Earlier quoted context omitted.

If “to get the machine to do exactly what you want” is an important goal, I'd recommend C or C++. Those are well known tools for those purposes. FP languages are rather about getting more ideas from math into how you structure your code.

I don’t think you need to go that low level. I find it much easier to optimize around things like memory layout, allocation patterns and cache effects even in Java and C# compared to (essentially) any functional language. I think this is just a feature of imperative languages over functional ones. Functional languages are excellent for many things, but not for this stuff.

Where should I look to learn about doing those things in Java? Last time I tried looking for guidance I mostly found people saying it's not worth the effort since the JVM JIT will do better.

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

#262

Post by asjw » Thu, Oct 17, 2019, 9:52 PM UTC

jcelerier wrote: post #241

js8 wrote: post #142

Earlier quoted context omitted.

> FP will always occupy a niche because of where it sits in the abstraction hierarchy At some point in history, people stopped worrying about not understanding compilers, how they allocate registers and handle loops and do low-level optimizations. The compilers (and languages like C or C++) became good enough (or even better than humans in many cases) in optimizing code. The same happened with managed memory and data…

> At some point in history, people stopped worrying Did they ? Because I keep seeing people around me who want to get into FPGA programming because they aren't getting enough juice from their computers. Sure, if you're making $businessapp you don't care but there is a large segment of people who really really really really want things to go faster, with no limits - content creation, games, finance... hell, I'd sell a…

Large as in 1 out of 1.000

The point is that to be mainstream it's enough to be used by one major app store

How many apps care about FPGA or what compilers do, given that they don't even know what the underlying OS does or when and why memory is allocated?

I work in finance, even there performances are for niche projects, the bulk of the job is replacing excel macros with something slightly less 90s style.

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

#263

Post by Litmus2336 » Thu, Oct 17, 2019, 9:54 PM UTC

jackhack wrote: post #182

js8 wrote: post #142

Earlier quoted context omitted.

> FP will always occupy a niche because of where it sits in the abstraction hierarchy At some point in history, people stopped worrying about not understanding compilers, how they allocate registers and handle loops and do low-level optimizations. The compilers (and languages like C or C++) became good enough (or even better than humans in many cases) in optimizing code. The same happened with managed memory and data…

Some people stopped worrying about not understanding compilers. They're not working on drivers, realtime (esp where low lag & jitter are concerned such as motion control), or high performance software of all stripes, trying to squeeze the most out of the available hardware. It's all about choosing the right tool for the job, and there is no right tool for every job. A guy generating sales reports has very, very diffe…

While I 100% agree with you, as a Java dev who is very interested in optimization (particularly register coloring) at a certain point I think you have to realize that any "compiler type" optimizations you do (Ooh, I'll optimize my variable declaration order to not spill to memory!) is just ignored and re optimized by most compilers worth their weight in salt. Therefore, it's totally counter productive. All the time spent worrying about GC lag is, IMO, wasted compared to other more productive things. I haven't programmed anything mechanical in over 6 years. Basically, for your average developer, while I highly recommend learning the whole stack, I don't believe the notion that understanding the whole stack will actually lead to tangible improvements for programmers. They'd be better served focusing purely on theory (and by theory I mean algorithms).

As a side note: I hate hardware, but I love graph algorithms, which is why I love register coloring so much :)

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

#264

Post by temp1999 » Thu, Oct 17, 2019, 9:56 PM UTC

AnimalMuppet wrote: post #191

soulofmischief wrote: post #147

Earlier quoted context omitted.

> In any case the point is this: I had some straight imperative code that was doing the same thing several times. In order to make it generic I couldn’t just introduce a loop around the repeated code, but I had to completely change the control flow. There is too much puzzle solving here. In fact I didn’t solve this the first time I tried. In my first attempt I ended up with something far too complicated and then just…

"It doesn't fit the way I think" != "I'm too stupid or lazy to figure it out". And why should s/he do so? Between the language and the programmer, which one is the tool? Should not the tool fit the human, and not the other way around? FP fits the way some people think. It doesn't fit the way others think. And that's fine. It's not a defect that some people think that way, and it's not a defect that some people don't.

To the second question, when you work in the industry you realize the answer is often the programmer.

Edit: There were a lot of questions in that comment.

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

#265

Post by willtim » Thu, Oct 17, 2019, 9:57 PM UTC

ansible wrote: post #201

grumpyprole wrote: post #192

Earlier quoted context omitted.

There is certainly prior art for complex games running smoothly in Haskell: https://wiki.haskell.org/Frag This particular solution used functional reactive programming, essentially a composition of signal/event processing functions/automatons.

Ten years ago, that was the only substantial game written in Haskell. That you're citing that same game now is a bit telling. Note the upload date: https://www.youtube.com/watch?v=0jYdu2u8gAU

Ok here's a talk about making Haskell games that took place last week: https://keera.co.uk/blog/2019/09/16/maintainable-mobile-hask... I don't deny that making games in Haskell is niche, but it's certainly possible. Frag was just an example I remembered (ten years is recent for an old git like me).

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

#266

Post by mbo » Thu, Oct 17, 2019, 10:00 PM UTC

jasode wrote: post #259

mbo wrote: post #254

EDIT: I wrote this comment before watching the video. I stand by this comment, but the video is very good and I wholeheartedly agree with its conclusions. 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…

>My personal belief? We just don't teach it.[...] Grads come out with a 4 year headstart on a non-FP paradigm, 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 popula…

> Why does functional programming need to be taught in schools but all the other various programming topics did 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.

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

#267

Post by gambler » Thu, Oct 17, 2019, 10:01 PM UTC

mbo wrote: post #254

EDIT: I wrote this comment before watching the video. I stand by this comment, but the video is very good and I wholeheartedly agree with its conclusions. 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…

What a coincidence. This sounds exactly like what happens with OOP. Every discussion here gets swarmed with clueless people who think Java is the apex of OO programming, because that's what gets taught in universities these days. They don't understand any of the core concepts that prompted Xerox Park to develop the OO paradigm in the first place. They aren't aware of any of the relevant research. They operate under the assumption that OO was born out complete ignorance of functional programming, even though people who kick-started its rise were keenly aware of Lisp (for example, Alan Kay frequently references McCarthy's work and research papers in his talks). Etc, etc.

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

#268

Post by kkarakk » Thu, Oct 17, 2019, 10:07 PM UTC

traderjane wrote: post #200

jackhack wrote: post #182

Earlier quoted context omitted.

Some people stopped worrying about not understanding compilers. They're not working on drivers, realtime (esp where low lag & jitter are concerned such as motion control), or high performance software of all stripes, trying to squeeze the most out of the available hardware. It's all about choosing the right tool for the job, and there is no right tool for every job. A guy generating sales reports has very, very diffe…

Yes, the pickup truck has its uses, but when we talk about high-level vs low-level programming, are we debating about the sedan or the pickup truck?

well as always when discussing functional programming people are not discussing the merits of functional programming but rather the merits of basically throwing away objective programming in favor of functional programming. That is ofcourse complete nonsense but modern computer science politics like all modern politics only deals in absolutes

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

#269

Post by DubiousPusher » Thu, Oct 17, 2019, 10:08 PM UTC

com2kid wrote: post #257

DubiousPusher wrote: post #256

Earlier quoted context omitted.

Classic games programmer logic. I've heard it a billion times. "X feature abstracts the hardware and therefore I could never use it for programming in my tiny niche and therefore it could never become popular." And how many of the top 10 languages are running in a virtual machine? Which could be literally doing anything under the hood with your allocations, caching, etc?! There is nothing wrong with saying, I don't s…

> And how many of the top 10 languages are running in a virtual machine? Which could be literally doing anything under the hood with your allocations, caching, etc?! VMs provide an environment, just like any other. Javascript articles are chock full of information on how to not abuse the GC by using closures in the wrong place. C#'s memory allocation is very well defined, Java has a million tuning parameters for thei…

Yeah, this is literally my point.

I was quibbling with the point that because FP languages often don't give low level control they can't become successful even though nearly every language on that top ten list suffers from the same perf oriented deficiency.

To write performant code in any of those top ten languages you have to understand the characteristics and nuances of the underlying tech stack.

And honestly people who don't write performant Java because they didn't bother to learn about the GC wouldn't have magically done otherwise writing C++. Trust me, that language does not intrinsically cause you to write performant code. It does intrinsically cause you to leak memory though.

But the bigger point is that in many domains performance is second to many other concerns. Like you said pick the languages that matches your needs.

So I think we pretty much agree.

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

#270

Post by AnimalMuppet » Thu, Oct 17, 2019, 10:15 PM UTC

temp1999 wrote: post #264

AnimalMuppet wrote: post #191

Earlier quoted context omitted.

"It doesn't fit the way I think" != "I'm too stupid or lazy to figure it out". And why should s/he do so? Between the language and the programmer, which one is the tool? Should not the tool fit the human, and not the other way around? FP fits the way some people think. It doesn't fit the way others think. And that's fine. It's not a defect that some people think that way, and it's not a defect that some people don't.

To the second question, when you work in the industry you realize the answer is often the programmer. Edit: There were a lot of questions in that comment.

I agree that it often works out that way... but it shouldn't.