Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Why Learn Prolog in 2021?

dstrohmaier.com

Post reply on HN
Print view View original

101–110 of 171 posts

Re: Why Learn Prolog in 2021?

#101

Post by dcolkitt »

KMag wrote: post #88

I'm not convinced there's great utility in smart contracts, but if there is, I think there's a huge utility in contracts being declarative and statically typed, to avoid many of the problems we've seen with existing contracts. In that case, a statically typed Prolog dialect would be a good starting point. The contract would be a set of declarative rules describing acceptable next states of the contract. To make the c…

Interesting point. The biggest counter-argument I see is the need for fine-grained optimization of gas usage. Especially given the crazy high fees as of late.

Hand-tuned imperative C enjoys a performance advantage over functional and declarative alternatives. So I’d imagine that imperative smart contracts are inherently easier to optimize than Prolog-style contracts.

Re: Why Learn Prolog in 2021?

#102

Post by tiew9Vii »

denimnerd42 wrote: post #82
ralphc wrote: post #76

Earlier quoted context omitted.

Why did they adopt Scala in the first place? I remember around 2012-2014 it was the hawtness. My guess is that there are languages that give you much of the power of Scala without the complexity - Kotlin, and modern Java, having caught up.

Scala got huge because of Spark. I'm a Scala programmer due to Spark. I love it.

Indeed. The only recent Scala job's I have seen in Australia have been Spark jobs because Spark uses Scala. Even these are diapering for Python Spark roles.

I've worked on a few big data projects for large companies. I have a huge dislike for them as mostly seem about how can we fuck over a customer to better the business or do shady stuff with the data rather than anything meaningful.

That and it's mostly just ETL, aggregating various data sources, cleaning, putting the data in some central location then running queries on it and the "If the only tool you have is a hammer, you will start treating all your problems like a nail." problem, tiny data sets going from NiFi / Hadoop / etc when `cat ... | awk ...` will be more than sufficient.

Re: Why Learn Prolog in 2021?

#103

Post by iso8859-1 »

qart wrote: post #8

I wonder... is it still justified to learn Prolog now? Aren't there better alternatives for logic programming in many other common programming languages? I mean http://minikanren.org/

There is also LogicT: http://hackage.haskell.org/package/logict

Since you'll eventually need some business logic, I don't see much point in Prolog either nowadays. Prolog-like code is a tiny part of your app, no need for a dedicated syntax. Do-notation is sufficient.

Re: Why Learn Prolog in 2021?

#104

Post by iso8859-1 »

triska wrote: post #15
qart wrote: post #8

I wonder... is it still justified to learn Prolog now? Aren't there better alternatives for logic programming in many other common programming languages? I mean http://minikanren.org/

How is this a better alternative? A major attraction of Prolog is that one can remove almost arbitrary parts of any pure program and still infer useful conclusions that hold for the original program. For example, one can remove a clause and thereby make the program more specific. One can remove a goal and thus make the program more general. This is possible due to the way the language is designed, the interplay of sy…

Why wouldn't that be the case for e.g. LogicT?

Prolog is _larger_ than LogicT. It is the additional syntax and runtime system in a custom Prolog implementation that needs to be defended, not the lack of it!

Re: Why Learn Prolog in 2021?

#105

Post by astrange »

flubert wrote: post #22
st1x7 wrote: post #14

How do you guys think about the opportunity cost of learning dead/dying/new/unpopular languages? Even with newer languages that are gaining popularity and are likely to be used in the future, I struggle to justify the time investment. I could be wrong but some of my concerns are: - my time is better spent getting deeper into some more popular language that I already know to some extent - unused skills deteriorate wit…

You will not make more money because you learn Prolog. I'd approach it like a hobby. Some people like collecting stamps. Some like pondering esoteric programming languages. With things like Prolog, you are closer to Nature, so to speak. Or maybe more mathematical. Learning about a lot of "modern" technology is a lot like memorizing minutia about the semi-arbitrary choices that have been fossilized and accumulating cr…

> You will not make more money because you learn Prolog.

I think you might if you use it properly. I definitely don't think you'll earn less money - it doesn't take enough time for that.

Re: Why Learn Prolog in 2021?

#106

Post by qart »

triska wrote: post #15
qart wrote: post #8

I wonder... is it still justified to learn Prolog now? Aren't there better alternatives for logic programming in many other common programming languages? I mean http://minikanren.org/

How is this a better alternative? A major attraction of Prolog is that one can remove almost arbitrary parts of any pure program and still infer useful conclusions that hold for the original program. For example, one can remove a clause and thereby make the program more specific. One can remove a goal and thus make the program more general. This is possible due to the way the language is designed, the interplay of sy…

I meant "better" in the sense that one can do logic programming from whatever language one is familiar with already, instead of installing and learning a whole new ecosystem. We would still have to learn logic programming.

Re: Why Learn Prolog in 2021?

#107

Post by zshrdlu »

st1x7 wrote: post #14

How do you guys think about the opportunity cost of learning dead/dying/new/unpopular languages? Even with newer languages that are gaining popularity and are likely to be used in the future, I struggle to justify the time investment. I could be wrong but some of my concerns are: - my time is better spent getting deeper into some more popular language that I already know to some extent - unused skills deteriorate wit…

If you're optimizing for a career or something, then it's probably prudent to learn the latest and greatest fad.

But sometimes you learn for fun, or out of sheer curiosity.

Re: Why Learn Prolog in 2021?

#108

Post by toast0 »

st1x7 wrote: post #14

How do you guys think about the opportunity cost of learning dead/dying/new/unpopular languages? Even with newer languages that are gaining popularity and are likely to be used in the future, I struggle to justify the time investment. I could be wrong but some of my concerns are: - my time is better spent getting deeper into some more popular language that I already know to some extent - unused skills deteriorate wit…

Dead/dying/new/unpopular doesn't matter too much. Does it work, and does it apply to problems want (or need) to solve matters much more. If it's dead, it may not get updates, so evaluate it based on what it is now and what you could conceivably add to it.

Learning a new language gives you more ways to understand languages you already know, so it has some value even if you don't use it professionally.

Unused skills deteriorate, but it's often easier to learn things the second time.

I wouldn't put too many languages on a resume. It's always relevant experience, relevant education, relevant knowledge. That means you can omit things if you don't think they're using BrainFuck in production, or you don't think they'd apprechiate the classy name. Maybe make a point of putting your favorite esoteric language just in case, but leave the others out.

Being able to pick up languages as needed is also a skill. At my last job, I was hired to do PHP work, but I learned Erlang on the job, as well as Applescript (ugh), got a lot less bad at C, wrote some perl and shell, and even had to write some python from time to time. And or course, I had to debug other people's Java, but didn't write any. I haven't seen a lot of positions where they explicitly hire for that, but it's sometimes what's needed.

Re: Why Learn Prolog in 2021?

#109

Post by siraben »

KMag wrote: post #88

I'm not convinced there's great utility in smart contracts, but if there is, I think there's a huge utility in contracts being declarative and statically typed, to avoid many of the problems we've seen with existing contracts. In that case, a statically typed Prolog dialect would be a good starting point. The contract would be a set of declarative rules describing acceptable next states of the contract. To make the c…

Lira[0] and its readable paper[1] is a good example of abstracting smart contracts into a statically typed, domain-specific language that describes the contract precisely at a high level. It's not Turing complete, which works for a large class of contracts (for instance, see the American and Asian options examples in [1]).

One concern with logic programming is cost of computation, on Ethereum every transaction has a gas associated with it and so you can't run computations that go over the gas available in a block.

Turner's ideas of Total Functional Programming[2] might have application in the smart contract space as well, since you disallow general recursion but allow structural recursion, you can likely precalculate or bound gas costs accurately ahead of time.

As for being statically typed, I completely agree, Solidity's poor design choices contributed to millions of USD in loss (e.g. DAO hack) because the developers were not able to easily reason about the implicit behavior or concurrency model.

[0] https://github.com/etoroxlabs/lira

[1] https://bahr.io/pubs/files/bahr15icfp-paper.pdf

[2] http://www.jucs.org/jucs_10_7/total_functional_programming/j...

Post reply on HN