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Comment by judofyr | Hacker News Reader

Hah, as someone who has studied at University of Oslo, many of the lecturers make sure that Simula isn’t forgotten, by constantly reminding us that it was the first language with classes etc.

Therefore, a few years back I decided to learn it a bit (I borrowed a really old book from the library) and solved one of the Advent of Code puzzles in Simula: https://github.com/judofyr/aoc2018/blob/master/day3prog.sim

I was actually very surprised at how “modern” it felt. However, neither this code nor the article touches on the real cool parts of Simula: Simulations based on coroutines.

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The new informatics building (well, not so new anymore, they built it around 2010) at the University of Oslo is named after Ole Johan Dahl.

Dahl was a professor of computer science at the University of Oslo and is considered to be one of the fathers of Simula and object-oriented programming along with Kristen Nygaard.

https://en.wikipedia.org/wiki/Ole-Johan_Dahl

https://www.uio.no/om/finn-fram/omrader/gaustad/ga06/

Many of the rooms inside of that building are named after programming languages.

http://magnus.li/ifirooms/

Naturally there is a room named Simula. And there are some rooms named after some big languages like Python and Java. Then there are also rooms named after some more niche languages, like Scheme. And even some obscure languages, like Ada.

Weren't Simula, Ada, Pascal and Oberon similar to each other syntax-wise? Begin-end etc.

There are similar syntax elements since Algol 60 was the common ancestor of all these languages; but in detail there are significant differences in syntax an semantics.

Ada, Pascal and Oberon are all Wirth-languages (the latter two directly, and the former indirectly). So they're very similar, yes.

Simila is not and, beyond some ALGOL-descended similarities, is quite different from the other three.

Ada is not a Wirth-language and only marginally inspired by Pascal. Wirth published Modula about the same time as Ada came around, but Ada is much more complex than Modula, with completely different features.

Ada's designers directly referenced Pascal's design and Wirth's theses to create Ada. They themselves call it a Wirth-language, as it follow's Wirth's principals.

Anecdotally, as someone who has coded extensively in Pascal (particularly the Object Pascal variant) and also (though, less so) in Ada; I'm baffled as to how anyone could look at the two and say they're only "marginally related". They're so similar that they're grouped together in much the manner C/C++ are, though Ada took a much harder compatibility break than C++ did:

https://p2ada.sourceforge.net/pascada.htm

> Well, what is that Ada language ? For here, it suffices to write: a superset of Pascal with some syntactical differences. Or a Super-Pascal. Or, a Pascal on steroids. In fact it's a better, redesigned language strongly inspired by Pascal. You'll see what I mean in the examples.

Pascal preceded Ada, but does not allow for coverage of most of the specialized topics that Ada does. For nearly every Pascal concept Ada took a different approach. Similarities are rather superficial.

To quote from https://dl.acm.org/doi/10.1145/956653.956654:

"Pascal itself only meets a small part of the Steelman requirements. Merely to attempt to extend Pascal would have been neither feasible nor a desirable approach. [...] Hence, the goal in the design of the Green language was to retain the Pascal spirit of simplicity and elegance but not necessarily the form of each Pascal feature"

So it's neither a "superset of Pascal" nor a "Pascal on steroids", but a new language design which meets (or better tried to meet since it is much more complex than Pascal) the "spirit of simplicitly" for completely different and much more complex requirements than Pascal did. It's definitely not a "Wirth language" and I don't know of any statement by neither Ichbiah nor Barnes where they would call it that way.

> In fact it's a better, redesigned language strongly inspired by Pascal.

Is the point you should have zeroed in on, not the thrown away comments. If you had, you would realize everyone is saying the same thing as you.

> It's definitely not a "Wirth language"

I specifically stated in my original comment that it was indirectly so, via it's Pascal lineage. If you want to jump through hoops to disavow it of it's clear and self-avowed forebear, go for it. There's nothing to be gained from continuing down this line of argumentation for me.

For some reason you seem to assume that taking inspiration from a language necessarily leads to a very similar language; there is no reason for this assumption; the language authors themselves have told us in the Rationale in what way they were inspired (see the quote in my previous comment). Those who consider Pascal and Ada to be very similar should study both languages more intensively, and not draw their conclusion from a few superficial features; furthermore, they fail to recognize the enormous difference in scope; Pascal offers a small fraction of the features of Ada and cannot be very similar for this reason alone.

Here is a simple example; both Pascal und its descendants suffered and still suffer from the dangling else problem; Ada solved this by adding end if and elsif, i.e. by integrating structured statements with blocks (Wirth himself came to a similar solution in Modula); superficially you still see the same Pascal keywords, but it's a different and much better approach.

Ada is neither indirectly a Wirth language; Wirth had nothing to do with it at all and came to quite different solutions in his later languages than the Ada authors.

I didn't assume anything, my point and reasoning was laid out and provided. You can disagree with it all you like, I don't care.

My opinion doesn't matter; it's what the facts say.

Ada isn’t that obscure, it outranks Scheme in the TIOBE index, for example.

If you are full-stack it probably seems obscure, and fortran seems outdated. But depending on your country, if you are safety critical embedded it is potentially the only option. It is in the top 2-3 in any case.

Edit: to finish my thought, if you are in physics or meteorology fortran is still common as well. There are a lot of software niches, and full-stack web dev is just the largest, at least as represented at HN, embedded might have more people if you combine planes, trains, automobiles, industrial, manufacturing, and more visibly IOT.

As of today, Fortran is newest and the oldest programming language with its most recent standard in 2023 and its first draft as the first high level programming language in 1954.

ADA was also used as the basis for Oracle PL/SQL, and the later ISO SQL/PSM standard.

These are very much alive, and implemented in major modern databases.

"SQL/PSM is derived, seemingly directly, from Oracle's PL/SQL. Oracle developed PL/SQL and released it in 1991, basing the language on the US Department of Defense's Ada programming language."

https://en.wikipedia.org/wiki/SQL/PSM

University of Oslo may have a room named after Simula, but that's nothing compared to Aalto University in Finland, they even have a computer science professor named Simula: https://people.aalto.fi/olli.simula

And the old(er) building right next to it is named after Kristen Nygaard.

Simula was used as the first programming language for informatics students at the University of Bergen until the mid 1990s, when they switched to Java. I was among the last batch of Simula students there.

When I was at UiO ('93), they did more than that: The introductory CS course required us to use Simula. We had to do several projects in it.

Of course at the time there were people on staff who had written books about it.

Do you remember how Kirkerud (the lecturer and textbook author) opened the semester stating with absolute certainty that AGI would never, ever be reached in our lifetime, or even the next several centuries?

I don't, but I mostly ignored the lectures as I'd been programming for most of my life already at that point, so I read the textbooks and showed up to the groups (the TA for my group was a member of Crusaders[1], which was fun). I think I attended a grand total of two lectures.

I do remember we found a really embarrassing algorithm choice in the Stack class, though (push and pop at the time were O(n), as it used a singly linked list that they iterated through recursively to find the top of the stack... we found that out on a group project where we kept running out stack space because of the recursion...)

[1] https://demozoo.org/groups/12/

NTNU still has at least one course that uses Simula for coursework. TTM4110 - Dependability and Performance with Discrete Event Simulation. An interesting course but without anyone who had real experience with the language teaching it, it was a slog to get through.

That's amazing, thanks for pointing out. Which compiler did you use to run Birtwisle's DEMOS?

I believe we used GNU Cim for the coursework, but it's some years since I took this class personally so I can't say for certain.

Thanks. Do you happen to remember whether the referenced course material was specifically describing the use of DEMOS and Simula as well?

Yes, the material was specifically describing DEMOS and Simula. The coursework was all about the dependability and performance of a simulation we had to program using DEMOS. Interesting course really, but a bit let down by teaching assistants who didn't know the material very well.

I believe CIM does the work of compiling C as well, but i may be misremebering.

Do you happen to have a PDF of the course material which you could share? I will contact the course admin otherwise.

Yes, CIM is generating C and uses the available C compiler behind the scenes.

I don't have a copy unfortunately.

The course admin might be on holiday but it's worth a try.

I can check tomorrow if I still have acess to the course resources

Ha, that’s interesting. I used to TA parts of that course; I had to learn Simula and Demos (a simulation library). If I recall correctly it was the first run of the course, and I had to develop some of the labs.

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