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Amzi Prolog becomes open source

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Re: Amzi Prolog becomes open source

#31

Post by nickpsecurity »

frik wrote: post #22
nickpsecurity wrote: post #9

So, PROLOG people, how excited should anyone be about this? This vs SWI, Visual Prolog, Prolog in a LISP like Allegro, or alternatives like Mercury. Is this significant in general or just for their community of users?

Triva: IBM Watson uses Prolog for its reasoning.

Shows it's still useful for sure. But, Watson uses a lot of techniques for it's operation with several languages integrated together w/ Prolog just one. And it does it on this hardware: "Watson employs a cluster of ninety IBM Power 750 servers, each of which uses a 3.5 GHz POWER7 eight core processor, with four threads per core. In total, the system has 2,880 POWER7 processor threads and 16 terabytes of RAM." (Wikipedia)

My house might burn down haha. It would be interesting to know a complex, useful, performant application coded entirely in PROLOG that wasn't a Visual Prolog IDE or something. ;) A list of those with what advantages and headaches Prolog gave the developers would be a nice start.

Re: Amzi Prolog becomes open source

#32

Post by nickpsecurity »

cyphar wrote: post #17
nickpsecurity wrote: post #16

Earlier quoted context omitted.

You can have all of the key freedoms with the restriction that they're paid for. This continues development, maintenance, and support. I'm not speculating as there's software with source available developed through commercial licensing. So, "free as in Stallman" software might be a dichotomy with proprietary but not "free as in free enough for many people." That exists and can flourish further with right mix of organ…

> You can have all of the key freedoms with the restriction that they're paid for. None of the four essential freedoms mention price. I work for a free software company which sells that software. I don't know what you're referring to. I clearly said that "free and commercial software are a FALSE dichotomy" -- meaning that you can have commercial free software. > So, "free as in Stallman" software might be a dichotomy…

"I clearly said that "free and commercial software are a FALSE dichotomy" -- meaning that you can have commercial free software."

Oh, I apologize. I clearly misread that exact statement. I bet it's because free, commercial, and false in same sentence almost always are arguing against what you said. That the two can't be combined. Whereas, we're arguing in different ways that they can. I must have skimmed it with my brain jumping right past the actual words to its intuitive guess of what they meant. At least I see how I failed. :)

"Proprietary software is software that takes away your freedom to use, modify and distribute the software. You can pay for free software and you can pay for proprietary software"

What firms are bringing in billions licensing or selling free software? I need a list of successful companies longer than Red Hat that can compete in both investment and lawsuits with big, proprietary firms. You can sell truly free software but almost nobody will buy it w/ you being super-niche in revenue. Whereas, useful and proprietary software can bring in significant money from customers esp in enterprise or government scenes. The proprietary ones just tend to scheme on customers, disappear, and other stuff. The free ones often aren't developed much, maintained, and so on.

My concept is to give you all the freedoms except for free distribution for a given project. You can use, modify, whatever the software as long as you pay the non-profit that develops, maintains, and supports it. You can also re-distribute that to other paying customers of the project. If non-profit stop supporting or distributing it, it goes BSD or Apache immediately per terms of the license or charter.

What are you missing other than widespread, free distribution in this model? As in, the availability of freeloaders that rarely contribute crap back. Do note that the project can give free copies in exchange for testing/feedback to get many eyeballs effect. Can also give discounts or free copies to academics to get their improvements.

What's left? Seriously, as I'm trying to see how close proprietary, shared source can get to FOSS without loosing the "sustainable, cash flow" part.

Re: Amzi Prolog becomes open source

#33

Post by nickpsecurity »

microtonal wrote: post #14
nickpsecurity wrote: post #9

So, PROLOG people, how excited should anyone be about this? This vs SWI, Visual Prolog, Prolog in a LISP like Allegro, or alternatives like Mercury. Is this significant in general or just for their community of users?

I work in academia, where SICStus is usually the most popular besides SWI Prolog. If SICStus went open source, that would be big news for me/us. This not so much. If SICStus went open source or free for academic use, I would probably use that in my research/courses over SWI Prolog. Mostly because of familiarity, performance, and compatibility reasons.

So, that's two votes for SICStus. What do you use Prolog for with what advantages?

Re: Amzi Prolog becomes open source

#34

Post by nickpsecurity »

kev009 wrote: post #11
nickpsecurity wrote: post #9

So, PROLOG people, how excited should anyone be about this? This vs SWI, Visual Prolog, Prolog in a LISP like Allegro, or alternatives like Mercury. Is this significant in general or just for their community of users?

I worked at a place a handful of years ago that used SICStus ( https://sicstus.sics.se/ ) because it was quite a bit faster than the other implementations. I'd like to revisit prolog, I think it is an underused language in industry.

So, that's two votes for SICStus. What did you use Prolog for with what advantages?

Re: Amzi Prolog becomes open source

#35

Post by Avshalom »

nickpsecurity wrote: post #29
YeGoblynQueenne wrote: post #20

Earlier quoted context omitted.

>> I went through their "Nani Quest" tutorial and that gave me positive memories of Prolog that I revisited later. Yeah, that's a great tutorial to the language, I learned a buttload from that when I was doing my degree. Not to look down on Learn Prolog Now! and others, but this is how to teach Prolog to university students.

Ok, that's two seconding that one. My references are overloaded as is but I'll add Nani Quest to give to anyone starting with Prolog. Note: Your alias is hilarious. Nice one.

Just a note on Nani Quest/Adventure in Prolog: it doesn't work in SWI-pl. I gave it a shot about 6 months ago and got to chapter 7 before stuff stopped working right. It was an excellent tutorial up to that point though.

Re: Amzi Prolog becomes open source

#36

Post by nickpsecurity »

Avshalom wrote: post #35
nickpsecurity wrote: post #29

Earlier quoted context omitted.

Ok, that's two seconding that one. My references are overloaded as is but I'll add Nani Quest to give to anyone starting with Prolog. Note: Your alias is hilarious. Nice one.

Just a note on Nani Quest/Adventure in Prolog: it doesn't work in SWI-pl. I gave it a shot about 6 months ago and got to chapter 7 before stuff stopped working right. It was an excellent tutorial up to that point though.

Porting the rest might make for a nice CompSci project for someone in that niche.

Re: Amzi Prolog becomes open source

#37

Post by YeGoblynQueenne »

Avshalom wrote: post #35
nickpsecurity wrote: post #29

Earlier quoted context omitted.

Ok, that's two seconding that one. My references are overloaded as is but I'll add Nani Quest to give to anyone starting with Prolog. Note: Your alias is hilarious. Nice one.

Just a note on Nani Quest/Adventure in Prolog: it doesn't work in SWI-pl. I gave it a shot about 6 months ago and got to chapter 7 before stuff stopped working right. It was an excellent tutorial up to that point though.

Welcome to Prolog portability hell :)

Note that Swi Prolog introduced some very big changes in version 7.0, that break interfaces left and right. It's to (Swi) Prolog what 3.4 is to Python. So if you were trying to follow Nani Quest with Swi 7.x and it gave you trouble, I'd try installing an earlier version.

I was on LPA Prolog when I did Nani Quest and I don't remember having issues, but it's been a while so I'm not sure.

Re: Amzi Prolog becomes open source

#38

Post by YeGoblynQueenne »

nickpsecurity wrote: post #29
YeGoblynQueenne wrote: post #20

Earlier quoted context omitted.

>> I went through their "Nani Quest" tutorial and that gave me positive memories of Prolog that I revisited later. Yeah, that's a great tutorial to the language, I learned a buttload from that when I was doing my degree. Not to look down on Learn Prolog Now! and others, but this is how to teach Prolog to university students.

Ok, that's two seconding that one. My references are overloaded as is but I'll add Nani Quest to give to anyone starting with Prolog. Note: Your alias is hilarious. Nice one.

:)

Re: Amzi Prolog becomes open source

#39

Post by cyphar »

nickpsecurity wrote: post #32
cyphar wrote: post #17

Earlier quoted context omitted.

> You can have all of the key freedoms with the restriction that they're paid for. None of the four essential freedoms mention price. I work for a free software company which sells that software. I don't know what you're referring to. I clearly said that "free and commercial software are a FALSE dichotomy" -- meaning that you can have commercial free software. > So, "free as in Stallman" software might be a dichotomy…

"I clearly said that "free and commercial software are a FALSE dichotomy" -- meaning that you can have commercial free software." Oh, I apologize. I clearly misread that exact statement. I bet it's because free, commercial, and false in same sentence almost always are arguing against what you said. That the two can't be combined. Whereas, we're arguing in different ways that they can. I must have skimmed it with my b…

> What firms are bringing in billions licensing or selling free software?

I work for SUSE, which is a free software company. Red Hat is another, as you mentioned. I found a list on Wikipedia[1] which has quite a few entries (though quite a few of those companies either no longer exist or were bought out by companies that don't exclusively work on free software).

> You can sell truly free software but almost nobody will buy it w/ you being super-niche in revenue.

That depends on your business model. The SUSE (and Red Hat) business model is to sell you a complete operating system which you are guaranteed to have support for. This is paid for by license costs for the base system and "modules" which are other pieces of software. If a user decides to install software which they didn't pay for, we don't support such a configuration if it breaks. Support in this case is not just support in setting up the system, it's also security updates and bug fixes (which are sometimes written by us and contributed back to the community). This sort of business model allows you to sell completely free software, because you're not selling the actual software you're selling licenses and support.

> My concept is to give you all the freedoms except for free distribution for a given project.

That would then be considered proprietary software in the strict sense of the word. It's better than nothing, but you have no practical freedom in that case because you cannot share your improvements to create a community -- one of the goals of the free software movement. The main thing to know is that free software is meant to mean that you cannot become entirely dependent on a company to support you. If you don't have the freedom to distribute modified and unmodified copies then you're (practically) at the mercy of the company that gave you the software.

> Seriously, as I'm trying to see how close proprietary, shared source can get to FOSS without loosing the "sustainable, cash flow" part.

Personally, I would never buy such software. I understand why it seems to be valuable to you to remove the free distribution freedoms of your users, but I don't agree with the logic. The problem is that you're still trying to "just sell the damn code", which doesn't guarantee you revenue with free software licenses (you can still sell it, but it's possible for a user to share the code with others without you knowing about it). Now, it's not very likely that many users would actually share the code (unfortunately), but it is possible. So, now you have to ask the question "what should I be selling". If you sell support (clients pay for you to develop new features for them, providing security fixes, bug fixes, etc) then you can make money selling completely free software. If you're scared of someone making money from your code, make it GPL and then you can take their changes back into your software.

Free software and proprietary software have only one difference which is how their distributed. Proprietary software is distributed in binary form only. Free software is usually distributed in binary and source form, but you can also distribute it in binary form with a link to where the source code is (and you can make it only be available to your customers -- that's still free software).

[1]: https://en.wikipedia.org/wiki/Category:Free_software_compani...

Re: Amzi Prolog becomes open source

#40

Post by YeGoblynQueenne »

microtonal wrote: post #21
YeGoblynQueenne wrote: post #19

Earlier quoted context omitted.

I'm first of all excited by the fact that this made first page on HN. I didn't realise there was that much interest in Prolog news (as in more than two or three people). Also, having more open-source Prolog engines is a very good thing, both for the language and for the project itself. For the project, it's good because it makes it easier for a community to grow around it. Swi has benefited enormously from its popula…

The problem is there are subtle differences between implementations that bite you in ways you never thought possible, and it's just aaaargh hard to get the same program running in the same way on two different Prologs. Or even between versions of the same implementation. E.g., I know of one project that sticks with SICStus 3, because in SICStus 4 findall/3 removes blocked goals from copied variables. This system reli…

>> Or even between versions of the same implementation. E.g., I know of one project that sticks with SICStus 3, because in SICStus 4 findall/3 removes blocked goals from copied variables. This system relies quite heavily on blocked goals and working around this change turned out to be too expensive.

When you say "blocked goals" do you mean it like:

:-block(a_block). % ... stuff ... :-end_block(a_block).

That sort of thing? Anyway yeah, sounds typical :/

With Swi I hurt a little recently when an update screwed up some of my stuff but then that was my fault for doing hacky tricks and trying to use modules as they're not meant to be.

>> In both cases, there are good reasons for the changes, but it makes portability hard.

Oh indeed. I started using 7.x the moment it was out pretty much, knowing that it means I'm tied to Swi for good and bad, but there's much more good than bad and so far I haven't regretted it.

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