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Also: 21 Hylomorphisms and nexuses from Pearls of Functional Algorithm Design: https://dai.fmph.uniba.sk/courses/FPRO/bird_pearls.pdf


You've got the right idea. A program is a proof for the proposition made by its type. Only for the right languages though, and not in the naive sense of `assert(1+1 == 2)` proves the assertion.


OK, not what I expected. Surely a spec is a spec, the program fulfils the spec hopefully, and the proof is that the program implements the spec. How do you see it? thanks


Curry Howard shows that for a logical proposition (A) with corresponding constructive proof (B), there will be a type (A') with program (B'). It's not about proving desired properties of programs. However, you can use the CH principles to do this too, as long as you can encode the proposition about a program in its type. This will not often look like the dataflow type of the naive program though. Look at software foundations for real detail, I'm not expert at this stuff, just aware of the basics.


If someone can learn C type syntax this is MUCH simpler. That doesn't mean you don't have to spend a little bit of time learning how it works, but it is not some kind of number-theory level maths construction only accessible to savants.



15 minutes is not a long time. Easily understand doesn't mean instantly understand with no background reading.


You're just ignoring what he is saying.


What part am I ignoring?


> In other words, baloney. If you don't do that kind of programming, that stuff is very opaque.

That part.


Well, I interpret that as the assertion that it's more opaque than other types of programming. But I disagree and think that it is actually simpler in terms of the syntax and amount of prior understanding required. My blunt reply is that to assert that a particular example is inaccessible but then only to have dedicated 15 minutes to prove so is silly. I'm sure most people who seem to suggest that this stuff is opaque had no problem learning PCRE or complicated SQL joins and also didn't complain that it took more than 15 minutes to do so. Of course TT is a deep field and there are many complicated parts of it, but the syntax, rules and the example given are not opaque and very understandable to anyone who can tackle languages and abstraction.


Okay then. Please give some links to the following.

– Lambda calculus tutorial that gets you up to what you need to understand the referenced paper in 15 minutes

- A description of Hoare notation that I can also understand to adequate depth to understand the referenced paper, also in 15 minutes

- A description of classical logic etc. etc. 15 minutes

- A description of intuitionistic logic etc. etc. 15 minutes (presumably in how it differs from classical)

These would be very useful. If you can also explain them in a way that would allow me to use the information I've learnt in an hour to do something useful with programs like represent them, transform them, verify them against a specification, I would gladly spend a couple of weeks or a month doing that, genuinely.

If you can't do any of these things, please stop posting how easy it all is


Mate, the point I was making is that 15 minutes is not a reasonable time frame to learn new programming concepts in.


You're right, I should read more carefully. Nonetheless, my point still stands, if you can give me some resources to learn these things, with considerably more than 15 minutes allowed, and bearing in mind I have no one to ask when I get stuck, and at my end aim is to actually use these things rather than treat them as interesting (which I already find them so) then I'd be grateful.


Pithy but useless sentiment.


So if you lost the weights how is that not killing the AI? Is it because it lacks the death experience? If so what about bitrotting the weights incrementally and degrading its inputs?


The AI is digital. It is 1s and 0s and lives in discrete changes.

Living creatures are not digital.


So if you implemented it with analog circuits that would satisfy your criteria?


It’s amazing to me that anyone considers AI at all similar to biological humans. Shows how warped HN is


The universe is quantized, according to quantum physics. That means living creatures are effectively digital.


Yeah same! It really was a tricky one for me: https://github.com/sordina/advent2021/blob/solutions/src/Adv...


The HTTP examples are fine, but a lower-level network module would enable all sorts of amazing plugins like a JDBC style ecosystem (WDBC?).


The binary representation is a neat idea. I found the trickiest part of this problem for me was interpreting an expanding boundary of the considered world: https://github.com/sordina/advent2021/blob/solutions/src/Adv...


> the rest of the input image consists of dark pixels (.)

This key bit of information seems to be missing in the originally posted problem, which your link clarifies!


> generates more than 20 million dollars a year of revenue

and

> team is 3 people

and

> post COVID, budget is really tight

Why? All technical details aside if this can't be addressed I wouldn't even bother trying unless I owned stock.


For all we know it's a car auction website and it selling 500 $40,000 cars.

Like the company actually buys the cars and sells them. $20 million revenue, cost of goods $18.5 million.

For all we know this website could be replaced with eBay or a cheap car dealer SAaS website.


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