If you are just going to use `TAGBODY` and `GO` to implement this ... in a goto based languages like C I don't think you would be needing a condition system. In C a nested function can also jump into a parents goto label. No one probably uses it, but just saying!

Also how similar is this to promises in javascript ?

It positively cannot, because,

1. There is no such thing as a nested function in ISO C. It's a GCC extension.

2. Let's try it the GCC extension:

  #include <stdio.h>
  
  int main(void)
  {
     void foo()
     {
       goto out;
     }

     foo();
     puts("skipped");
  out:
     return 0;
  }

  nestedgoto.c: In function ‘foo’:
  nestedgoto.c:7:6: error: label ‘out’ used but not defined
        goto out;
        ^~~~

  #include <stdio.h>

  int main(void)
  {
     void foo(void *target)
     {
       goto *target;
     }

     foo(&&out);
     puts("skipped");
  out:
     return 0;
  }

  $ ./nestedgoto 
  *** stack smashing detected ***: <unknown> terminated
  Aborted (core dumped)

  [8]> (tagbody
         (funcall (lambda () (go out)))
         (print 'skipped)
         out
         (print 'out))

  OUT 
  NIL

The book contains an implementation of dynamic variables in C, though, which uses a GCC cleanup extension; the example code contains the contributed code examples for that showing various means of implementing dynavars in C.

Promises are asynchronous while signaling and condition handling is fully synchronous; I don't know what kind of parallel one can draw here. If anything, a promise's .catch(...) method may act like a CL HANDLER-CASE; the promise becomes resolved, just a different code block is executed in case of a failure.

Well, once upon a time it used to be setjmp/longjmp; currently it's based on a re-implementation of a mechanism that is almost setjmp/longjmp in assembly language.

To use setjmp/longjmp for implementing sophisticated exception handling, you have to maintain your own unwind chain on the stack and unwind that.

Before invoking longjmp, you have to walk your own frames that are chained through the stack, and do all the clean-up yourself, up to that frame that holds the jmp_buf where you want to jump.

TXR correctly maintains the chain connectivity even under delimited continuation support, which works by copying sections of the C stack to and from a heap object.

When a delimited continuation is restored (involving copying it out of a heap into a new location on the stack), the frame linkage in the restored continuation is fixed up and hooked up. The continuation can throw an exception and unwind out through the caller that invoked it.

Here is the implementation of unwind-protect operator in the interpreter:

  static val op_unwind_protect(val form, val env)
  {
    val prot_form = second(form);
    val cleanup_forms = rest(rest(form));
    val result = nil;

    uw_simple_catch_begin;

    result = eval(prot_form, env, prot_form);

    uw_unwind {
      eval_progn(cleanup_forms, env, cleanup_forms);
    }

    uw_catch_end;

    return result;
  }

In the virtual machine, there is a uwprot instruction instead:

  1> (disassemble (compile-toplevel '(unwind-protect (foo) (bar))))
  ** warning: (expr-1:1) unbound function foo
  ** warning: (expr-1:1) unbound function bar
  data:
  syms:
      0: foo
      1: bar
  code:
      0: 58000004 uwprot 4
      1: 24000002 gcall t2 0
      2: 00000000
      3: 10000000 end nil
      4: 24000003 gcall t3 1
      5: 00000001
      6: 10000000 end nil
      7: 10000002 end t2
  instruction count:
      6
  #<sys:vm-desc: 9432d90>

The function that the vm interpreter dispatches for uwprot is simplicity itself:

  NOINLINE static void vm_uwprot(struct vm *vm, vm_word_t insn)
  {
    int saved_lev = vm->lev;
    unsigned cleanup_ip = vm_insn_bigop(insn);

    uw_simple_catch_begin;

    vm_execute(vm);

    uw_unwind {
      vm->lev = saved_lev;
      vm->ip = cleanup_ip;
      vm_execute(vm);
    }

    uw_catch_end;
  }

What I meant with the promises was, If you could pass three closures ... like success, error, restart could you get some kinda condition system ?

And that also only handles the case of "help I'm ded get me out of here". What about signals that do not expect to be handled, and instead are used to transfer information higher up the stack by invoking a handler function specified in the dynamic environment? That's a valid use of the condition system, as outlined in the book.

Works for perl because while we don't (yet, somebody's working on one) have an unwind-protect like primitive, perl's refcounting system provides timely destruction so you can use a scope guard object stuffed into a lexical on the stack whose DESTROY method does whatever unwind cleanup you need.

Ironically, the main reason I'm not using this so much at the moment is that it isn't compatible with the suspend/resume code around promises provided by Future::AsyncAwait and I'm heavily using that in my current code, but at the point where I need both I'll probably attempt to nerd snipe one of the relevant authors into helping me figure it out.

(EDIT: Aaaaactually, I think I might already know how to make them work together, naturally an idea popped into my head just after I hit the post button ... using Syntax::Keyword::Dynamically and capturing a relevant future higher up the chain of calls should allow me to return-to-there cleanly, then I "just" need to cancel the intermediate futures to simulate unwinding ... but I'll have to try it to find out)

Thank you for mentioning Worlogog, I'll include that in the book. How should I credit you?

"Matt S. Trout (mst)" is good - I'm probably better known by my IRC nick than my full name in geek circles ;)

I imagine that is the reality of everyone who tries to implement a condition system in a language where the default behavior is to immediately unwind the stack by throwing some sort of an exception.

If I were to want to continue discussing this, do you happen to kick around anywhere on IRC that would be suitable?

https://www.oreilly.com/library/view/open-sources/1565925823...

> Three great virtues of programming are laziness, impatience, and hubris. Great Perl programmers embrace those virtues. So do Open Source developers.

> But here I’m going to talk about some other virtues: diligence, patience, and humility.

> If you think these sound like the opposite, you’re right. If you think a single community can’t embrace opposing values, then you should spend more time with Perl. After all, there’s more than one way to do it.

To me it's one of the best bits of writing I've read, regardless of the argument.

As a random example:

> Here is the shape of the big bang, and of stars, and of soap bubbles

it's just a perfect sentence.

The blunt fact of the matter is - A majority of the movies would gain more by giving it away to the public domain because most movies fail. Radio did not kill Art. Internet is the new radio.

The same is true even for software. 80% of business fail. It would not matter if they gave their code away. GPL based business have made billions, i'n not even talking about open source and have more users than some of the biggest "startups".

Among the minority that made it "big" copyright contributed maybe 5% to the success. IP allows big companies to bully creators, lie to consumers and bully independent companies that they perceive as threats.

In Music, Code, Science ... openness has lead to more innovation. Movies and Games present an interesting case. They have plenty of upfront costs. Games have already embraced some notions of the freemium mode. It would be really interesting if 100 million dollar movie is entirely funded by the people. There is nothing stopping that from happening. Copyright, Patents should last at-most 1 year.

To your point, the vast majority of media and software is proprietary, though much of it is supporting in nature and not directly for sale. Nevertheless, shouldn’t publishers be free to choose how they fund their creations?

If we take away the option of artificial scarcity then an entire highly trained professional class will be out of work. While I don’t think Jonny Depp, for example, is worth $650M [1], I don’t personally think that’s a great option for the editors, writers, extras, gaffers, and many other professionals that work together to make great media.

Companies are motivated to maximise the revenue from making this stuff. If they could make more money without copyright, they would have done this already. (And radio is a terrible example: commercial radio simply plays advertising for artists, called “songs”, 24x7)

[0] https://en.wikipedia.org/wiki/List_of_most_expensive_films

[1] https://www.theguardian.com/film/2020/jul/13/johnny-depp-tel...

Of course. The problem is when they demand that goverments take away their ciziten's natural rights to copy and share information in order to support their chosen business model. If publishers want society to make their business model possible by being given special "rights" and having public institudions enforce those "rights" then it is very much up to all of society to choose if that is acceptable.

Remember copyright is an entirely artificial construct meant to benefit society by encouraging creators to produce content. It is my and many others opinion that the current state of copyright is a very one sided affair that benefits mainly big corporations while having numerous negative effects on society.

> If we take away the option of artificial scarcity then an entire highly trained professional class will be out of work.

Unlikely. There will always be a demand for entertainment and people interested in filling that demand will find a way to make it worthwile.

But even if the entire entertainment industry would instantly disappear then that would still not be an argument to uphold unjust laws. Professions becoming obsolete with progress is entirely natural. People can adapt.

The law can change tomorrow with the stroke of a pen and society won't owe them anything for these past "investments" no matter what their expectations were. Which, of course, is why they invest so much in politics and astroturf campaigns to head off any attempt to actually change the law to something more in line with what most people actually think is right. (If you applied the principle of estoppel and required anyone who had ever violated copyright law to suit words to actions and vote against it then you probably couldn't even get a quorum in favor, much less a majority.)

> The problem with this line of reasoning is that all property is an artificial construct.

Property rights arise naturally as a result of scarcity. Someone has to have the right to decide how the scarce resource will be used or it might as well not exist.

"Property" rights in things that are not scarce are a purely artificial construct.

> For starters, the GPL, CC, Apache and many other free licenses rely on copyright to work.

Copyleft licenses were created as a reaction against copyright. Sometimes they overstep their bounds, true—especially the less permissive variants. However, in general, if copyright and software patents did not exist then there would be no need for any of these licenses.

> The wholesale destruction of journalism, for example, has clearly damaged society. Part of the damage has been caused because Google and Facebook have subverted copyright to their own causes.

Taking it at face value, this appears to be an argument against copyright? Not that I really agree that Google and Facebook are primarily to blame. The public simply prefers to be entertained and reaffirmed rather than informed. If anything, copyright reinforces this outcome since you can't copyright facts (and rightly so); as such, actual journalism, uncovering the facts of the situation, has become a cost center to be minimized, whereas the "expression" is heavily subsidized via copyright monopoly.

What you say is literally true, but because most investment ends up as wages, such an act would literally destroy tens of billions of dollars of working capital, and put a hundred thousand people out of work overnight.

I assume that's not an outcome you actually advocate.

> Property rights arise naturally as a result of scarcity

Rubbish. The whole concept of rights is almost entirely artificial [0]. For most of history, property and other rights were determined by whoever had the biggest army. Jesus, many people still don't have the right to their own bodies in some places in the world.

The idea that rights of any kind are somehow anything other than a set of cherished beliefs codified in law, is nonsense.

> Copyleft licenses were created as a reaction against copyright.

I think the situation is much, much more complicated than that, but it is a side issue of this conversation at best.

> this appears to be an argument against copyright... The public simply prefers to be entertained

You surely can't blame people for wanting to be entertained? Are you saying you never watch something fun?

In any case, weak and misapplied copyright laws have enabled Google and Facebook, in particular, to concentrate the important elements of journalism and present it to their users in a way which reduces the diversity of all journalism. They show just enough to get away with "fair use" while ensuring that the likelihood of people clicking outside the walled garden is minimised.

Imagine what these companies would do to us if basic copyright was even weaker. Do you think Facebook would link to an article it can just copy? 2 billion+ people on the earth would have just one web browser and it would never - not be allowed - to leave fb.com.

That is not a future I want.

[0] https://en.wikipedia.org/wiki/Rights

[1] https://en.wikipedia.org/wiki/Magna_Carta

I don't wish misfortune on anyone, and I expect there would be a transitional period in any real-world implementation, but just the same I cannot possibly justify continuing this parasitic situation any longer than absolutely necessary. If I were presented with a button that would eliminate copyright law instantly, globally, and permanently, I would press it without hesitation—and then get to work dealing with the inevitable fallout.

> For most of history, property and other rights were determined by whoever had the biggest army. Jesus, many people still don't have the right to their own bodies in some places in the world.

You are obviously referring to legal recognition of rights, not the rights themselves. The law is artificial, founded for the most part on non-defensive application of force to achieve a desired outcome, and doesn't correlate very well with the rights that people naturally possess. Some legal systems are better than other in this regard. No law which comes from a government will ever fully recognize natural human rights because, quite simply, that would put them out of business. However, here in the U.S. we at least explicitly recognize that there are rights which humans naturally possess ("endowed by their Creator"—whatever that happens to mean to you) which do not derive from the law, but rather have priority over it. There is a difference between what the law says you may do without penalty and what you may rightfully do, and when the two are in conflict it is the law which is wrong, no matter how popular the law might be or how much force can be brought to bear to back it up.

> You surely can't blame people for wanting to be entertained? Are you saying you never watch something fun?

I'm not blaming them. I'm just saying that there isn't a strong market right now for actual journalism. It's thankless work, for the most part, with or without copyright.

> In any case, weak and misapplied copyright laws have enabled Google and Facebook, in particular, to concentrate the important elements of journalism and present it to their users in a way which reduces the diversity of all journalism. They show just enough to get away with "fair use" while ensuring that the likelihood of people clicking outside the walled garden is minimised.

Are you trying to say that copyright should be expanded to cover facts and not just expression? That it should be illegal to quote or paraphrase a small portion of a copyrighted work? I believe the majority would side with me in vehemently disagreeing. Keep in mind that (in the U.S.) the exceptions for fair use are the only reason why copyright law was not declared wholly unconstitutional on 1st Amendment grounds. Freedom of speech is far more important than this runaway social engineering experiment known as copyright. (IMHO they gave in too easily. Copyright law violates the 1st Amendment and freedom of speech even with fair use.)

I can’t reconcile these two statements. People would definitely die if you pushed that button; I don’t think you want that.

> here in the U.S. we at least explicitly recognize that there are rights which humans naturally possess

Perhaps true, but only for certain values of ‘human’.

> Are you trying to say that copyright should be expanded to cover facts and not just expression? That it should be illegal to quote or paraphrase a small portion of a copyrighted work?

I think it’s pretty clear that I’m saying that fair use has been subverted by companies for profit, and that eliminating copyright will make things far worse.

> Freedom of speech is far more important than this runaway social engineering experiment known as copyright

Given the rate at which people are getting sick and dying in the US right now, I’m not certain that the “runaway social experiment of free speech” - as moderated and directed by the copyright infringing trolls at big social media - is working out too well for you guys either.

> Copyright law violates the 1st Amendment and freedom of speech even with fair use.

Didn’t you just essentially argue that the law is not morally authoritative?

You clearly believe that there exist natural rights. I happen to believe that the right to control the things I create is natural. Just because something can be copied easily doesn’t abrogate my natural rights, any more than the fact that your genome can be copied abrogates yours.

Despite what you think, its entirely possible and natural for me to suffer a loss if you copy something that I created, particularly if creating it was expensive for me, and your copying it prevents me from making good my loss.

While there is much I find dismaying about copyright law, there is nothing unnatural about it.

80% movies don't need the 100 million dollar budget and I'm pretty sure Johnny Deepp would be happy to release Edward Scissorhands to the public domain.

Most big movies make their money by single day screenings and releasing movies at different dates in different regions with market buzz.

> If we take away the option of artificial scarcity then an entire highly trained professional class will be out of work.

Interestingly your argument fails for porn. Its about 1/4th the size of hollywood.

How about publishers own the copyright and creators own the copyright instead of commoditising a copyright artefact ?

I assure you musicians can survive and Depp can do some theatre. Most EDM is essentially copyright free, especially techno. 1 year of exclusivity is fine. Fuck NDAs.

These days the cost of production has gone down so I think you will see more indie media taking advantage of that. The average budget for a reasonable movie is less than 5 million, heck even 500k dollars going by kickstarter funded movies.

In terms of $100M movies, I think they almost all suck, but that was the value you suggested. I’d say that no movie needs to cost $100M!

But plenty of movies cost $10M. If it takes 100 people a year to make a movie then you can easily spend $10M on salaries and overheads alone.

> Interestingly your argument fails for porn

Does it? I’d guess that the average porno costs a few hundred bucks to shoot, and takes a couple of hours. There is easily 100x more hours of porn produced per day than narrative fiction, and yet it only makes 25% of Hollywood, and notoriously, the actors are frequently exploited. I’d say that porn is a warning of danger rather than a proof of success!

> Depp can do some theatre

When was the last time you paid to go to the theatre?

> Most EDM is essentially copyright free, especially techno. 1 year of exclusivity is fine. Fuck NDAs.

My raver days are (sadly) behind me, but sure, OK, like porn, EDM can be produced with little investment. So what? No everything that is good is also cheap or easy to build.

> These days the cost of production has gone down so I think you will see more indie media taking advantage of that.

I’m a huge fan of indy media but, because of that, I pay for it, and I don’t like it when people freeload.

> The average budget for a reasonable movie is less than 5 million

I think you’re just making things up now, but even so, 5 million is a buttload of money that you need to get back. Few people are gonna spend that sort of money with no expectation of recouping it.

I too can ignore every big budget predictable cliche and say so what. Lets ignore the successes of alternatives.

Is Kanye West and Britney Spears the best you can do with millions of dollars ? I'll stick to punk and EDM ... no thanks.

> I’m a huge fan of indy media but, because of that, I pay for it, and I don’t like it when people freeload.

Is copyright / patents the only way to finance and get money back ?

Absolutely not. Thats the argument I am making.

https://en.wikipedia.org/wiki/Base_rate_fallacy

The problem is that some productions are simply expensive. Think about sending an imax camera to the space station. There is literally no way to make that cheap. And why concentrate only on music and movies, what about games? What about journalism? There are a huge number of industries that depend on at least some form of copyright, even if not specifically the bastard form that exists at this moment.

> Is copyright / patents the only way to finance and get money back ? Absolutely not. Thats the argument I am making.

But as far as I can tell, you’re only arguing against copyright, you’re not actually making an argument for a viable alternative, and that is my problem.

Just because you dig EDM and punk, and these specific types of music can be made on the cheap, doesn’t mean all good media can be made cheaply. Just because most $100M movies suck doesn’t mean that $10 million movies shouldn’t be made.

Accept that, and then explain to me how to repeatedly raise the $10 million investment needed to create high quality, high cost products that will be given away for free, no strings attached. I think you’ll find that the problem is that doing so is incredibly hard and extremely risky, which is why nobody is doing it.

https://christianengstrom.wordpress.com/the-pirate-party-on-...

Also, I believe nobody should go to jail or be bankrupted for copying digital works.

And what do you know? Two randos came to an amicable position on an Internet forum :) next stop, world peace!!

Cheers

What exactly about being in the public domain would help a movie "gain more" if it hadn't had a successful box office run previously? "GPL-based businesses making billions" does not strike me as a meaningful comparison here. ("Well, 'Cats' is a fiasco, but if we give it away for free we can make a killing selling enterprise service contracts for it!")

The author is trying to move knowledge off facts of things and intellectual processes and into the realm of emotion and kind compassion. A kind compassion is simply a mask which hides a different form of power seeking. Which is on-point for the current cultural shifts we are going through, he mirrors the nature of humans at this very moment.

The author seeks to replace existing knowledge in the reader, destroying all the knowledge of facts and feelings in an attempt to keep relationships on track. It is a mistake.

You can disagree and be right in a calm manner and also in an angry manner without changing the content or aim of your speech. The article aims too low at a reader who is willing to accept what is written without thinking critically or taking a higher perspective gleaned from education. Like most psychologists he risks undermining those that are experiencing these mental processes as a function of striving to achieve a goal. The undermining of useful definitions is supposedly necessary for maintaining a relationship without looking at other solutions first.

Every medium is a social one if you think about it and every social medium is political.

The medium has and always will be the message and when you get to the core you understand the message is simply the audience.

Do you think "primitive" civilizations compared to ours didn't have social media before the advent of the tweet?

They were operating on levels we haven't even begun to understand in our foolish pride.

We're as primitive as we were at the invention of electric light and our technological advancements have outpaced our morality. We're just amplifying the hysteria and confusion with our automated algorithms and always-on engagement and now every poor schmuck has a voice where once it was limited to the elites. You should be grateful that Twitter has democratized the inane blatherings of the proletariat to drown out the voices of so called authority.

1. Information dissemination

2. Coordination

3. Persuasion

4. Feedback gathering

5. Social grooming (jokes, status updates, needs ...)

6. Artistic self-expression

All these are fairly reasonable in any social media.

Conflicting communication via threads is where they fail. Trolling is as old as threads.

1. When you start each circle

2. Length of the wires

It would be neat if actual numbers were shown and rates could be adjusted via a hard reset.

I was messing with a procrastination model in https://bit.ly/2ZPNXdo .. it seems if you are not feeling good and you procrastinate less, things improve over time. To test this, decrease the feel good and then decrease procrastination.

https://en.wikipedia.org/wiki/DYNAMO_(programming_language)

I came across stocks and flows a couple of years back and it certainly changed my thinking. Interestingly this is something we sorta commonly use in backend dashboards to understand the behavior of the system, especially with regards to data. I always thought there ought to be some similar ways to envision economy with this and I find infographics trying to bridge the gap albeit still static though.

- Thinking in Systems, also by Meadows

- Business Dynamics, by Sterman (slowly working through this)

- Strategic Modelling and Business Dynamics, by Morecroft

- General Systems Thinking, by Weinberg (on Leanpub you can get the PDFs, it's 4 books there, as I recall the first two were published as one book when it was published as a paper book)

http://pespmc1.vub.ac.be/books/IntroCyb.pdf

Meadows is interesting and a quick read, but shallow. Morecroft is a thorough read and a decent alternative to Sterman's if you can't get it. But Sterman's really is the best textbook.

I worked through (most of) Morecroft because it was available through O'Reilly's online library and I had a subscription through work. I read Meadows specifically because of the leverage points essay, and wanted to see what else she had. It's definitely shallower than the others, but I think a good introduction because of its relative brevity.

Might be interesting to you based on the above.

I've seen Loopy before, but Sheetless looked more like existing tools with storied histories (Stella etc).

Like any forehead-smacking moron who can code I have sometimes considered writing my own because the thing I miss most of all in systems dynamics tools is being able to use git and write tests. But I know now that writing real software is really hard.

https://www.wsj.com/articles/the-tech-whiz-behind-vine-and-h...