The Go programming language is not only partly inspired by Wirth's work (Robert Griesemer, one of the "founding fathers" of Go, studied at ETH Zürich), it also has this goal of simplicity: it started out with fewer (but powerful and unfortunately often underestimated) features than other languages, and while it has added more complexity over the years (modules, generics, ...), this has happened at a much slower rate than with other languages.
If being simple gives us go, perhaps we should try to drop simplicity for simplicity's sake and accept that complicated things might be needed occasionally?
Go is a modern programming language, which suffers from a lot of issues that were well known at the time of its creation.
Besides being a saner alternative to C in regards to userspace stuff, and also bare metal stuff (for the belivers in automatic memory management), there isn't much else about it in language features to call home about.
> Except for some minor points, Component Pascal is a superset of Oberon-2. Compared to Oberon-2, it provides several clarifications and improvements.
The similarities are hard to overlook, replace curly braces by BEGIN / END Pascal style syntax and you are more than halfway there.
Of course Go has added features that were not present in Oberon / Component pascal, the implicit interfaces come to my mind, Go channels also. But inherently its a Wirthian language.
Also Griesemer is not the only Oberon connection of Go. Rob Pike has studied the Oberon system when developing the ACME editor for Plan 9 (Source: https://wiki.c2.com/?OberonOperatingSystem).
I honestly think Oberon didn't get named, because at the time of launching Go, the Pascal / C conflict was a lot more present in the memories of people so there was nothing to gain from pointing out these roots.
It is not uncommon for programming languages to not talk about their roots during launch due to politics (Java for example traces its object-oriented roots to https://en.wikipedia.org/wiki/Strongtalk a typed Smalltalk descendant, but was advertised as a cleaned-up C++).
I don't see what this all has to do with Component Pascal (the language report is not by Mössenböck, but by Pfister et al., btw.). You should instead have a look at the Newsqueak publications. There are more similarities of Go with Algol than with Oberon. Newsqueak reused a few features of Pascal, some of which are still present in Go.
The Acme editor has similarities with the original, text based Oberon system user interface, which unfortunately shares the name with the language, but is not the same thing. The user interface of the Oberon system again looks like a stripped down version of the Cedar environment developed at PARC (where Wirth had his sabbatical).
Unfortunately, this graph is at least misleading, if not wrong. The middle path is overly prominent; the detour to Object Oberon (probably so that Griesemer's name is represented) is amusing. Actually there should be a direct line from Newsqueak to Go. Aleph's brief intermezzo is mostly historically relevant for Go, not technically. The path from C should actually point primarily to Newsqueak (in addition to Pascal). Technically, there would be a very thick arrow from Newsqueak to Go, a slightly less thick from C to Go, and a very thin one from Oberon-2 and a few other languages. But as a highly simplified representation of the languages and people directly and indirectly involved and the chronological sequence, the graph is ok.
Here's the accompanying text from The Go Programming Language for that line in the graph:
> One major stream of influence comes from languages by Niklaus Wirth, beginning with Pascal. Modula-2 inspired the package concept, Oberon eliminated the distinction between module interface files and module implementation files. Oberon-2 influenced the syntax for packages, imports, and declarations, and Object Oberon provided the syntax for method declarations.
So mostly packages and syntax - not the most exciting stuff, but the package concept contributes to enabling Go's compilation speed, so it shouldn't be disregarded. Ok, you can still argue that many or most of the C/Pascal-family influences were already present in Newsqueak (I'm only familiar with Pascal, C and Go, so I can't judge that), but I think it's understandable that they wanted to have the language the book is about at the focal point of the graph, and not one of its less successful and more obscure ancestors.
Thanks, I have the book. The major influence had Pascal on Newsqueak. I don't see any specific similarity between Modula-2 and Go. There are other languages which are at least as close or even closer. The last sentence is even wrong. Object Oberon is a completely different language in terms of OO. Go uses the receiver syntax of Oberon-2, which is a completely different concept than in Object Oberon.
it's true that golang is basically newsqueak with structural interface types, but newsqueak is pretty obviously strongly pascal-influenced. i agree that newsqueak shows significant c influence, but in most of the ways that c and pascal differ, it follows pascal. and it seems unavoidable that griesemer spending his grad school at wirth's school hacking on wirth's language oberon would have influenced the taste he applied to golang
Oberon+ is a superset of Oberon 90 and Oberon-2. Here is more information: https://oberon-lang.github.io/, and here is the current language specification: https://github.com/oberon-lang/specification/blob/master/The.... I already had valuable feedback here on HN concerning the channel extensions. Further research brought me to the conclusion, that Oberon+ should support both, channels and also monitors, because even in Go, the sync package primitives are used twice as much as channels. Mutexes and condition variables can be emulated with channels (I tried my luck here: https://www.quora.com/How-can-we-emulate-mutexes-and-conditi...), but for efficiency reasons I think monitors should be directly supported in the language as well, even if it might collide with the goal of simplicity.
i don't know that much about concurrency in general, so take this with a grain of salt
i feel like monitors are potentially an improvement over bare locks, but they tend to perform poorly in manycore settings and are still vulnerable to deadlock, perhaps more so due to their implicit nature. (i see that you point this out with respect to java, and also that it doesn't really have monitors.) fundamentally, blocking synchronization of any kind is incompatible with modularity
you misspelled brinch (rip)
there are lots of versions of actors, and the most influential one effectively didn't have any concurrency at all, so it's important to disambiguate in the text that you're talking about the one in agha's 01985 dissertation, which is also very influential. also your footnote says it's from "1986"; is that a different document by agha with the same title?
objects with their own threads (like concurrent actors or like processes in csp or erlang) are not the same thing as monitors, contrary to your assertion in the 'concurrency in oberon' section. there is a well-known duality between message passing between threads and control passing between monitors, but the mechanisms have quite different ergonomics and common failure modes
it's surprising that in a discussion that surveys original-modula, modula-2, csp, erlang, active oberon, c, c++, concurrent pascal, object pascal, superpascal, joyce, newsqueak, old squeak, alef, limbo, golang, java, and ada, you didn't mention javascript at all. in browsers and node, javascript's concurrency model was originally that of original oberon — each event handler runs to completion in succession — which strongly suggests that the concurrency facilities it has added more recently might be worth a look. those are python-like async/await, sometimes caricatured as 'colored functions', and web workers. also it might be worthwhile to at least mention the π-calculus
my uninformed viewpoint is that js, erlang, haskell with its stm, and (non-async!) rust are the languages with the most promising approaches to the concurrency problem. all four of them work hard to be safe (unlike the entire rest of the js language), though i think their concurrency safety guarantees are all to some degree fragile. except maybe haskell, which i haven't tried
your reference [31] https://www.jtolio.com/2016/03/go-channels-are-bad-and-you-s... doesn't purport to show that no single concurrency construct is adequate, as you claim, or even that communication channels are inadequate; rather, it argues that the implementation in golang of that concept is inadequate, because golang implements them inefficiently, because it can't garbage-collect processes, because there are some design errors, and that because golang also offers other concurrency constructs (as you propose for oberon+), it's hard to avoid concurrency bugs. though certainly not conclusive evidence, this runs strongly against the conclusion you are using it to argue for
also your bibliography incorrectly abbreviates 'per brinch hansen' as 'hansen, p. b.' rather than 'brinch hansen, p.' a few times
i hope this is helpful, and i'm glad to see you're exploring how to solve this problem! feel free to copy or excerpt my comments elsewhere if you think it would be useful
Thank you very much for your time and your feedback which I really appreciate.
> but they tend to perform poorly in manycore settings and are still vulnerable to deadlock [..] fundamentally, blocking synchronization of any kind is incompatible with modularity
Do you have references for this? With the selected version of signals (only an await procedure, no explicit signal required), the only way for a deadlock from my point of view is when a protected procedure calls directly or indirectly another protected procedure of the same monitor, thus trying to acquire the same lock twice. But this can be detected by the compiler. Or did I miss something?
> you're talking about the one in agha's 01985 dissertation
> objects with their own threads [..] are not the same thing as monitors
I'm not aware I claimed this. Will check whether the formulation is misleading. Actually I wanted to point out that the "objects with threads" in Active Oberon give little added value and are not "active objects" at all.
> you didn't mention javascript at all
Well, the intention was not to have a general discussion about concurrency in all programming languages; I'm primarily interested in the relatives of Oberon, plus a selection of languages based on CSP. I just mentioned Erlang because it is a prominent example of an Actor language. But I will have a look at more recent JS developments for ideas compatible with Oberon.
> javascript's concurrency model was originally that of original oberon
Just because of the message delegation/handler concept (which existed before Oberon)? I wasn't aware that there is a direct connection of JS and Oberon (it is not even mentioned in the 2020 JS HOPL paper).
> are the languages with the most promising approaches to the concurrency problem
Do you think that JS concurrency is better than Go concurrency, i.e. channels aren't worthwhile at all? Why?
> it might be worthwhile to at least mention the π-calculus
From my perspective, that's sufficiently covered by [13], as far as the concepts might be useful for Oberon+. Which relevant idea do you think is specifically missing?
> your reference [31] doesn't purport to show that no single concurrency construct is adequate
The paper explicitly states "Unfortunately, as it stands, there are simply a surprising amount of problems that are solved better with traditional synchronization primitives than with Go’s version of CSP. [..] The summary here is that you will be using traditional synchronization primitives in addition to channels if you want to do anything real", from which I conclude that channels alone are not good enough; this conclusion is also supported by [32], where one of the tables demonstrates that the analyzed projects use low-level primitives twice as much as channels. I agree with the author that there are problems which can more elegantly be solved with classic synchronisation (including monitors), regardless of possible design issues of Go; we could use channels to emulate those (as demonstrated), but for efficiency reasons I preferred to directly add monitors (as Go did with adding low-level primitives instead). I think monitors are still better than the Go sync package, and if everything else fails Oberon+ could access pthreads by FFI. But that's actually the main point where more thinking and discussions are required.
Maybe he contributed the receiver syntax to Go, we can only assume. But anyway it's not that much Oberon in Go, much less than pop culture assumes. By the end of the day, the two languages mostly share the concept of static typing (with Go even stricter than Oberon), modularity and garbage collection; otherwise they have a different focus (concurrency in Go, type extension and minimalism in Oberon).
Only if consider the Oberon from 1987 and nothing else in the Oberon ecosystem.
Nothing else in the ETHZ group doing Oberon related research counts from that point of view, if it didn't had the touch of Niklaus Wirth himself adding lines to the compiler.
> Only if consider the Oberon from 1987 and nothing else in the Oberon ecosystem counts [..] if it didn't had the touch of Niklaus Wirth himself
I considered all languages where Wirth was at least co-author, because that was the claim made in this thread. I assume you mean Active Oberon; but this version is even further away from Go (closer to Ada95, Java and ConcurrentPascal). And I'm neither a "Wirthian" nor do I believe in personality cults, if it is that what you assume.
I mean every single Oberon variant produced by ETHZ students during their PhD, all of them.
For me that is always what I cared about in the Oberon universe.
Original Oberon was interesting for 1987, and Oberon-07 is kind of interesting from Niklaus Wirth pursue of minimalism point of view.
Most more interesting are all the works produced in the context of languages and operating systems research at ETHZ in the context of Oberon derivatives.
One of this students brought his education to another programming language.
From my point of view, we will keep on disagreeing, regarding Oberon.
> From my point of view, we will keep on disagreeing, regarding Oberon.
I don't even know in what respect we disagree; maybe it's also due to the language barrier. If you have specific questions about my projects, feel free to ask.
One might argue that a lot of languages depend heavily on compile time code generation. Just because Rust's macros, or C++'s template metaprograms are sweeping their generated code under a stylish rug doesn't mean it's not happening. Slowly.
