Comment by Animats

3 months ago

- Looser functions (badly chosen name)

Timeouts on calls are, as the OP mentions, a thing in Erlang. Inter-process and inter-computer calls in QNX can optionally time out, and this includes all system calls that can block. Real-time programs use such features. Probably don't want it on more than that. It's like having exceptions raised in things you thought worked.

- Capabilities

They've been tried at the hardware level, and IBM used them in the System/38, but they never caught on. They're not really compatible with C's flat memory model, which is partly they fell out of fashion. Capabilities mean having multiple types of memory. Might come back if partially-shared multiprocessors make a comeback.

- Production-Level Releases

That's kind of vague. Semantic versioning is a related concept. It's more of a tooling thing than a language thing.

- Semi-Dynamic Language

I once proposed this for Python. The idea was that, at some point, the program made a call that told the system "Done initializing". After that point, you couldn't load more code, and some other things that inhibit optimization would be prohibited. At that point, the JIT compiler runs, once. No need for the horrors inside PyPy which deal with cleanup when someone patches one module from another.

Guido didn't like it.

- Value Database

The OP has a good criticism of why this is a bad idea. It's an old idea, mostly from LISP land, where early systems saved the whole LISP environment state. Source control? What's that?

- A Truly Relational Language

Well, in Python, almost everything is a key/value store. The NoSQL people were going in that direction. Then people remembered that you want atomic transactions to keep the database from turning to junk, and mostly backed off from NoSQL where the data matters long-term.

- A Language To Encourage Modular Monoliths

Hm. Needs further development. Yes, we still have trouble putting parts together. There's been real progress. Nobody has to keep rewriting Vol. I of Knuth algorithms in each new project any more. But what's being proposed here?

- Modular Linting

That's mostly a hack for when the original language design was botched. View this from the point of the maintenance programmer - what guarantees apply to this code? What's been prevented from happening? Rust has one linter, and you can add directives in the code which allow exceptions. This allows future maintenance programmers to see what is being allowed.

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Animats

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dkarl  3 months ago

> - A Language To Encourage Modular Monolith

> But what's being proposed here?

I read it, and to me it seems like they're worried about the wrong things. As I understand it, they're worried about the difficulty and hassle of calling unrelated code in the monolith, and proposing things that would make it easier. But that's wrongheaded. Monoliths don't suffer because it's too hard to reuse functionality. They suffer because it's too easy. Programmers create connections and dependencies that shouldn't exist, and the monolith starts to strangle itself (if you have good tests) or shake itself to pieces (if you don't) because of unnecessary coupling. You need mechanisms that enforce modularity, that force programmers to reuse code at designated, designed module interfaces, not mechanisms that make it easier to call arbitrary code elsewhere in the monolith.

In my opinion, a great deal of the success of microservices is due to the physical impossibility of bypassing a network API and calling the code of another service directly. Because of this, programmers respect the importance of designing and evolving APIs in microservices. Essentially, microservices enforce modularity, forcing programmers to carefully design and evolve the API to their code, and this is such a powerful force for good design that it makes microservices appealing even when their architectural aspects aren't helpful.

A language that made it possible to enforce modularity in a monolith as effectively as it is enforced in microservices would make monoliths a no-brainer when you don't need the architectural aspects of microservices.

  • gf000  3 months ago

    This is literally the core tenet of OOP, and arguably Java and friends did a decent enough job of that via encapsulation and visibility modifiers.

    • dkarl  3 months ago

      Not really. Look at any open source Java library, and you'll see that unless it's small enough to implement in a single package, it probably contains public classes that aren't meant to be part of the public API but are declared public so they can be used in other packages in the library codebase.

      That's why they introduced a module system for Java in Java 9. It sounded pretty cool to me when they announced it, but it was a bit too late to make much difference in the Java ecosystem (Java 9 came out 21 years after Java 1) and I haven't heard much about it since then.

      1 reply →

zozbot234  3 months ago

> Capabilities ... They're not really compatible with C's flat memory model ... Capabilities mean having multiple types of memory

C is not really dependent on a flat memory model - instead, it models memory allocations as separate "objects" (quite reniniscent of "object orientation in hardware" which is yet another name for capabilities), and a pointer to "object" A cannot be offset to point into some distinct "object" B.

> A Truly Relational Language

This is broadly speaking how PROLOG and other logic-programming languages work. The foundational operation in such languages is a knowledge-base query, and "relations" are the unifying concept as opposed to functions with predefined inputs and outputs.

mplanchard  3 months ago

> In general, while I can’t control how people react to this list, should this end up on, say, Hacker News, I’m looking more for replies of the form “that’s interesting and it makes me think of this other interesting idea” and less “that’s stupid and could never work because X, Y, and Z so everyone stop talking about new ideas” or “why hasn’t jerf heard of this other obscure language that tried that 30 years ago”. (Because, again, of course I don’t know everything that has been tried.)

  • Animats  3 months ago

    OK, a few things that languages ought to have:

    - Everything except C now has standard strings, not just arrays of characters. Almost all languages now have some standard way to do key/value sets. What else ought to be standard?

    -- Arrays of more than one dimension would be helpful for numerical work. Most languages descended from C lack this. They only have arrays of arrays. Even Rust lacks it. Proposals run into bikeshedding - some people want rectangular slices out of arrays, which means carrying stride info around.

    -- Standard types for 2, 3 and 4-element vectors would help in graphics work. There are too many different implementations of those in most language and too much conversion.

    Things to think about:

    - Rust's ownership restrictions are harsh. Can we keep the safety and do more?

    -- The back-reference problem needs to be solved somehow. Back references can be done with Rc and Weak, but it's clunky.

    -- Can what Rust does with Rc, RefCell, and .borrow() be checked at compile time? That allows eliminating the run-time check, and provides assurance that the run-time check won't fail. Something has to look at the entire call tree at compile time, and sometimes it won't be possible to verify this at compile time. But most of the time, it should be.

    -- There's a scheme for ownership where there's one owning reference and N using references. The idea is to verify at compile time that the using references cannot outlive the owning one. Then there's no need for reference counds.

    -- Can this be extended to the multi-thread case? There have been academic demos of static deadlock detection, but that doesn't seem to have made it into production languages.

    -- A common idiom involves things being owned by handles, but also indexed for lookup by various keys. Dropping the handle drops the object and removes it from the indices. Is that a useful general purpose operation? It's one that gets botched rather often.

    -- Should compilers have SAT-solver level proof systems built in?

    -- Do programs really have to be in monospaced fonts? (Mesa on the Alto used the Bravo word processor as its text editor. Nobody does that any more.)

    -- There's async, there are threads, and there are "green threads", such as Go's "goroutines". Where's that going?

    -- Can we have programs which run partly in a CPU and partly in a GPU, compiled together with the appropriate consistency checks, so the data structures and calls must match to compile?

    -- How about "big objects?" These are separately built program components which have internal state and some protection from their callers. Microsoft OLE did that, some .dll files do that, and Intel used to have rings of protection and call gates to help with that, hardware features nobody used. But languages never directly supported such objects.

    So there are a few simple ideas to think about.

    • pmontra  3 months ago

      > Do programs really have to be in monospaced fonts?

      Of course not. I've been using a proportional font for at least 10 years and I'm still in business working on code bases shared with developers using monospaced fonts. Both work, none disturb the other, proportional is easier to read as any book can demonstrate. Alignment doesn't matter much.

      6 replies →

    • zzo38computer  3 months ago

      > Everything except C now has standard strings, not just arrays of characters. Almost all languages now have some standard way to do key/value sets. What else ought to be standard?

      I think that character strings should not be restricted to (or generally expected to be) Unicode (although using Unicode and other character sets will still be possible).

      I also think that key/value lists should allow any or most types as keys, including references to objects. (PostScript allows any type to be used as keys except strings (they are converted to names if you use them as keys) and nulls.)

      I think that big integers (which can have a program-specified limited length in programming languages with typed variables) and arrays of fixed-length records (which C already has; JavaScript has typed arrays which is a more limited implementation of this) are also things that would be helpful to include as standard.

      > Arrays of more than one dimension would be helpful for numerical work.

      I agree with this too; it is a good idea.

      > Standard types for 2, 3 and 4-element vectors would help in graphics work.

      This is probably helpful, too, although they can be used for stuff other than graphics work as well.

      > Do programs really have to be in monospaced fonts?

      No, but that is due to how it is displayed and is not normally a feature of the program itself. Many people including myself do use monospace fonts, but this should not usually be required.

      > There's async, there are threads, and there are "green threads", such as Go's "goroutines". Where's that going?

      I had read about "green threads" and I think that it is a good idea.

      > How about "big objects?" These are separately built program components which have internal state and some protection from their callers. Microsoft OLE did that, some .dll files do that, and Intel used to have rings of protection and call gates to help with that, hardware features nobody used. But languages never directly supported such objects.

      I also think it is sensible to have components that can be separated from the callers, and that operating system support (and perhaps hardware support) for such thing might be helpful. I would design a programming language for such an operating system that would directly support such objects.

    • maleldil  3 months ago

      > - Everything except C now has standard strings, not just arrays of characters.

      Zig's strings are null-terminated arrays of bytes. It's an unfortunate mistake from an otherwise interesting language.

      1 reply →

andrewflnr  3 months ago

> - A Truly Relational Language

> Well, in Python, almost everything is a key/value store.

Why would that be anywhere near an adequate substitute? KV stores are not relational, they don't support relational algebra. KV stores in PLs are common as dirt, so if they were relevant to the question of ending relations in a language I think the author would have noticed.

pjmlp  3 months ago

Commercial image based systems have had source control like management for decades.

If anything many "modern" low code SaaS products are much worse in this regard, than what Lisp and Smalltalk have been offering for years.

9rx  3 months ago

> But what's being proposed here?

He proposes that there is a need for a way to connect modules, i.e. dependency injection, without the modules having explicit knowledge of each other, with compile-time verification that the modules being connected are compatible, without the interface song and dance.

zzo38computer  3 months ago

Many of these things (not only what you describe here but also the linked article) are stuff that I had intended to be available in the built-in command shell (called "Command, Automation, and Query Language", which is meant to describe some of the intentions) of an operating system design, so that they would have support from the operating system.

About capabilities, I think that capabilities should be a feature of the operating system, although hardware support would be helpful. However, I think that it could be done with tagged memory, without necessarily needing multiple types of memory, and programming languages such as C could still be capable of using them (although some things might not work as it would be expected on other computers, e.g. if you try to copy a reference to a capability into a memory area that is expected to be a number and then try to perform arithmetic on that number, the program is likely to crash even if the result is never dereferenced).

However, my idea also involves "proxy capabilities" too, so that you can effectively make up your own capabilities and other programs receive them without necessarily knowing where they came from (this allows supporting many things, including (but not limited to) many of the idea of "divergent desktop" of Arcan).

lispm  3 months ago

> The OP has a good criticism of why this is a bad idea. It's an old idea, mostly from LISP land, where early systems saved the whole LISP environment state. Source control? What's that?

Symbolics Genera can save (incremental and complete) images (-> "Worlds"). The image tracks all the sources loaded into it. The sources/files/docs/... of the software is stored on a central (or local) file server.

I can for example start an initial world and load it with all the wanted software in the various versions I want. Maybe I save a new world from that.

I can also start an pre-loaded world and incrementally update the software: write patches, create new minor/major versions, load patches and updates from the central server, install updates from distributions, ... Maybe save new worlds.

The "System Construction Tool" tracks what code is loaded in what version from where.

igouy  3 months ago

> The OP has a good criticism of why this is a bad idea.

They simply assert "twiddling a run-time variable for debugging in your staging environment can propagate straight into a bug on production".

As-if straight into production without re-testing.

> Source control? What's that?

"ENVY/Manager augments this model by providing configuration management and version control facilities. All code is stored in a central database rather than in files associated with a particular image. Developers are continuously connected to this database; therefore changes are immediately visible to all developers."

https://www.google.com/books/edition/Mastering_ENVY_Develope...

~

1992 Product Review: Object Technology’s ENVY Developer

http://archive.esug.org/HistoricalDocuments/TheSmalltalkRepo...

naasking  3 months ago

> Capabilities > > Capabilities mean having multiple types of memory. Might come back if partially-shared multiprocessors make a comeback.

I found this description amusing because all modern memory safe languages have capabilities, and they all have multiple types of memory: that's what an object is! Memory safety partitions memory into different types, and object references are capabilities!

What languages do next is where they break the security properties of capabilities: they add "ambient authority" and "rights amplification". Quick primer:

Ambient authority is basically the same problem as globally mutable state. Globally mutable state impedes modular reasoning about code, but if that state also carries authority to do something dangerous in the real world, like launch missiles, then it also impedes modular reasoning about security for the exact same reasons.

Rights amplification is the ability to turn a reference to an object with little to no authority, into a reference to an object with more authority. File.Open is the quintessential example, where you can turn an immutable string that conveys no authority, into a file handle to your root file system!

File.Open is also typically accessible to all code, meaning it's also ambient authority. This classical file API is completely bonkers from a security perspective.

So we already have capabilities, what we really need to do is to stop adding all of this insecurity! The developers of the E language actually showed that this could be done by making a capability secure subset of Java called Joe-E, which removed the parts of Java and the standard library that exposed ambient authority or rights amplification patterns. Most Java code could run unmodified.

And as for whether capability security will ever be adopted elsewhere, it already has been! WASM's WASI has capability security in its core design, because capability security is exactly what you need for good isolation and virtualization, which are the core properties WASM needs.

riffraff  3 months ago

> Source control? What's that?

I think squeak had Monticello for source control with their image based approach almost 20+ years ago and there was something else for smalltalk in the '80s too.

But yeah people like text and hate images, and I believe Pharo switched back to some git integration.