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aarroyocon Djota: A Djot Implementation in Prolog

Djot is a markup language similar to Markdown but with a different rationale. See more: https://github.com/jgm/djot#rationale . A Prolog implementation like this is based on Scryer Prolog, which is a system that makes working with strings very easy and efficiently.

aarroyocon Is wine fake?

That's also typical in Spain. In fact, most family restaurants offer free wine, but it's of that level of quality, so you usually mix it with sparkling water.

Also, it's typical of young people to mix cheap wine with Coca-Cola, and have parties with that.

aarroyocon The Ciao System

The real homepage https://ciao-lang.org/ has code examples. Spoiler alert: it is Prolog

aarroyocon The Ciao System

Well, it IS Prolog. Ciao conforms to the ISO Prolog standard. It adds a lot of things through a preprocessor though.

aarroyocon RISC-V based single board computers are getting there

I bought the Mango Pi MQ-Pro a month ago and while at first the software support was missing (only Tina Linux was available), later some ISOs started to appear. Right now I'm using the Armbian headless image based on Ubuntu 22.04[0] which works almost perfect and allows me to work on porting things to RISC-V.

[0]: https://bret.dk/armbian-on-the-mangopi-mq-pro/

aarroyocon Dogelog player is a Prolog system for the JavaScript and the Python platform

> One thing I've wondered about with such systems as performance: I would be nervous about pathological cases leading to really bad performance or even DOS attacks. My understanding of Prolog in particular is that sometimes I get in your program to run to completion requires a nontrivial understanding of the backtracking algorithm them so you can judiciously place cuts, etc.

That depends on which constructs are you using. It's perfectly fine to write modern Prolog code without any cut, but the sad thing is that those constructs (once/1, dif/2, if_/3, tabling, ...) aren't taught in most books out there (the exception is The Power of Prolog) which still perpetuates these ideas about Prolog.

aarroyocon Dogelog player is a Prolog system for the JavaScript and the Python platform

Tau Prolog is an ISO Prolog system from scratch and just for JavaScript. It tries to follow some of the innovations of Scryer and Trella Prolog. Dogelog inherits some stuff from Jekejeke Prolog and has an innovative GC.

aarroyocon The Power of Prolog

Isn't RETE a forward-chaining algorithm while Prolog is a backward-chaining language? I'm not sure you could use RETE for the actual Prolog semantics. Currently, fast implementations of Prolog use a virtual machine, the most popular is WAM, that can be compiled then to machine code (GNU Prolog does it). Also some implementations have JIT indexing, which improves performance too.

aarroyocon The Power of Prolog

This is one of the best resources for learning modern Prolog. It mainly uses Scryer Prolog, which is a still-in-progress open source Prolog system, but very promising and adheres to the ISO standard.

aarroyocon Europe is investing heavily in trains

There's no gauge change. Spain high-speed tracks already use the international one (older tracks still use Iberian gauge). There are already high-speed trains that go to France without stopping at the border.

aarroyocon 50 Years of Prolog and Beyond

The main difference is that CLIPS is a forward chaining rule system, while Prolog is backward chaining. This is a big difference in how rules are defined and how do you use them (in Prolog you start with a query always and you try to prove it, in CLIPS you just run it to get some rules dispatched).

However, Prolog is also a valid general purpose programming language, so you can actually implement forward chaining rule systems in them (see for example CHR[1] and Heiseneye [2]). CLIPS is not a general purpose programming language.

[1] https://www.swi-prolog.org/man/chr.html [2] https://github.com/IDLabResearch/Heiseneye

aarroyocon An embeddable Prolog scripting language for Go

IMHO you loose a lot of expresiveness. Real Prolog code is not just simple rules and facts. They can be more complex than that. For example, in my case, I'd like to use DCGs a lot, which are a bit difficult to translate using "normal languages" constructs. Many Prolog systems implement DCGs with Prolog macros because Prolog is homoiconic, which most normal languages aren't (Lisp is homoiconic too).

Also "logic" arithmetic (clpz, clpfd,...) is not the one that comes with normal languages and that breaks a lot of logical properties. Doing the sum of two variables in Java side will not respect logical properties. Standard is/2 in Prolog is also bad, but at least you can replace it with #= and that's it.

aarroyocon Teletext Archive – open repository for teletext recoverers

I think that's not possible on DVB-T (yes, there are countries like mine where DVB-T is used with Teletext). I wonder what are the options to recover teletext from today digital TV.

aarroyocon Vatican’s list of films

Watch The Mission if you haven't, the soundtrack is very good

aarroyocon Logica, a novel open-source logic programming language

SWI Prolog is a very nice Prolog but it is not standard anymore

aarroyocon Ask HN: Why aren't one-time sign in links more popular for authentication?

It's the way Spanish government webapps work with the citizens but it's a bit confusing to be honest. When it works it's perfect but the setup is complicated, so they're introducing an optional user/password login also.

aarroyocon School or Prison

My philosophy teacher said that both prisons and schools end up being a panopticon because you want the same in both places: maximize the feel of power of the authority, don't leave any place without surveillance,...

aarroyocon Ask HN: What are you surprised isn’t being worked on more?

Some of the things you say can already be achieved with Prolog DCGs, which are more or less like pattern matching over lists (usually lists of chars, but not needed).

aarroyocon The Secret Math Society Known as Nicolas Bourbaki

In my university in Spain, math students have the Saint Bourbaki day. That day is recognized holiday by the university and they don't have any classes.

aarroyocon Minitel: The Online World France Built Before the Web (2017)

In Spain we had Ibertex, which is basically the same technology (some minor improvements), but it wasn't as popular as Minitel in France.

aarroyocon Teletext Bad Apple

Very cool! I spent a lot of my youth navigating Teletext. Also lots of people doesn't seem to realize that Teletext is still alive and updated daily in some European countries like Spain.

aarroyocon Bitoduc: A French dictionnary for CS related words

Spanish also has "ordenador", which is the most common way to refer to a computer in Spain (I think in Hispanic America, "computador"/"computadora" is used more often but in Spain it feels like something old).

aarroyocon Ennio Morricone has died

I'm a very big fan of him. It's so sad but we all knew he was in the late stages of his life.

He was for me the biggest composer of the second half of 20th century, which just happened to do music for films (also for some Italian pop music, but it was less prolific there).

Requiescat in Pace. https://www.youtube.com/watch?v=Z3SAOQfMA44

aarroyocon The Eclipse Foundation Is Moving to Europe

There are other projects, nowadays it's more like the Apache Foundation. Some other big projects are Jakarta EE, Jetty, and Golo.

List here: https://projects.eclipse.org/

aarroyocon European mortality monitoring shows increase in excess mortality

That's what I'm saying. These graphs are too broad for a country because the numbers change a lot between cities. I'm expecting that some cities even report less deaths because of the lockdown (less risky activities, less traffic accidents, less labour accidents,...). So even if the numbers look similar to the ones of previous years, it is not distributed as other years.

aarroyocon European mortality monitoring shows increase in excess mortality

These kind of graphs, while useful, still miss a point. My experience in Spain is that there are a some hotspots like Madrid where hospitals and morgues are collapsed but other cities/villages, which have the same lockdown didn't have so many infected people per capita, so they will actually have probably the same or less mortality rates. The country on itself looks bad, but in the hotspots is terrible

aarroyocon Ask HN: Who Is Firing?

I agree. In Spain most people are getting ERTEs, which allow you to keep the job, the state pays 80% of your salary.

Also firing people is now temporaly banned (technically not, but it's much much more difficult to do until we're out of the state of alarm).

aarroyocon Coronavirus deaths of Wikidata notable people

In my country (Spain), fatality rates for March have tripled for what is usual. They don't know where to store so many corpses, in fact they're using ice skating places as morgues. So it's obviously more than a flu and the systems are collapsed.

aarroyocon Coronavirus deaths of Wikidata notable people

I think to be in the list you need to have a Wikipedia page before your death, but some of them may not be in the English edition as I've checked

aarroyocon Ask HN: What is your blog and why should I read it?

https://blog.adrianistan.eu

It's my Spanish blog about Prolog, Rust and Python mainly. I thought about opening a new one in English, to reach a more broad audience, but I will not write in two blogs at the same time and the Spanish blog maybe has more relevance due to the lack of blogs like mine in Spanish.