If you put chalk under a powerful microscope - <AUTHOR> https://twitter.com/ferrisjabr/status/1022534132415356928 <comment><USER2> Contrast this with the Hubble Deep Field image, which is an extremely tiny patch of the night sky. It's sizeis equivalent to a tennis ball at a distance of 100 metres, or ~110 yards.

And my god, it's full of stars. There's endless detail in the universe, whether you zoom in, or zoom out.

See: [https://upload.wikimedia.org/wikipedia/commons/6/69/NASA- HS2...](https://upload.wikimedia.org/wikipedia/commons/6/69/NASA- HS201427a-HubbleUltraDeepField2014-20140603.jpg)

<comment><USER3> here is a perspective video: [https://www.youtube.com/watch?v=q1mkjkTqg0Y](https://www.youtube.com/watch?v=q1mkjkTqg0Y)

<comment><USER4> The star UY Scuti is 2,500,000,000 kilometres in diameter.

It would take light nearly 2.5hrs to travel that far.

</comment></comment></comment><comment><USER5> That thread has some beautiful photos. This one is my favorite[1], it's amazing to me how intricate the math of an object can be at a microscopic level.

I mean look at the black and white 2x4, top one 2nd from the left, my mind instantly just wanted to plot that in Matlab and gaze at how complex the equation is!

[1] [https://twitter.com/ferrisjabr/status/1022890070531960837?s=...](https://twitter.com/ferrisjabr/status/1022890070531960837?s=09)

<comment><USER6> To be honest, I found that and the coccolith pictures quite unpleasant/uncomfortable to look at --- it could be because I'm somewhat trypophobic, since they caused me to feel the same "brain-melting" sensation and have the similar characteristic of many almost-regular-but-irregular edges. The "neural network dream" generated images did the same thing to me; I feel my brain heat up and sweat a little.

In contrast, something like a box of gears or related machinery parts, which theoretically is also full of edges, doesn't provoke the same feeling...

<comment><USER7> That's interesting because my first reaction seeing the photos was to think that "they look like a bunch of gears, huh that's neat".

Deep dream also made me feel calm, like I was watching a natural process, like a plant growing, or the rain falling. I hadn't had that kind of reaction to "computer" art before.

<comment><USER8> you will love the movie 'Annihilation' then, in case you haven't already watched it

</comment></comment></comment></comment><comment><USER9> It's easier to read this as an single unrolled post than as a set of tweets:

[https://threadreaderapp.com/thread/1022534132415356928.html](https://threadreaderapp.com/thread/1022534132415356928.html)

<comment><USER10> This looks like a very obvious cowpath that Twitter could pave. I just don't get why they haven't done it yet.

<comment><USER11> It's a slippery slope. If they do this, what's next? Where do they stop? What's it going to take for users to finally be satisfied?

(Edit: Don't understand the downvotes. Don't understand a lot of downvotes lately. Do I have a target on my back?)

<comment><USER12> It's entirely reasonable to want to be able to read a series of tweets that are meant to be read as one long tweet/block of text the way it was intended to be read. I don't understand how you think this is an unreasonable request, especially when tools exist to correct this issue with the max-character limitation Twitter has, or what "slippery slope" this could have.

You're getting downvotes because you're advocating something that makes entirely 0 sense from a usability perspective. And commenting on why you're being voted in a particular way is wholly against the guidelines:

> Please don't comment about the voting on comments. It never does any good, > and it makes boring reading.

<comment><USER11> If a series of tweets can easily be put into a defined order for consumption then why not just lift the max character limitation and let people make tweets as long as they want? Seems like it'd be an easy slide down that slope once you're on it.

<comment><USER12> There is no slope. Either the limitation is there, or it isn't. What comes after to call this a "slippery slope"?

And clearly the existing limitation is a pain in the ass, or else services that "unroll" multi-tweet text wouldn't exist. The limitation is completely arbitrary and clearly not entirely helpful, so a request to lift it is entirely reasonable.

<comment><USER11> I can easily imagine a series of changes that ultimately turns Twitter into something like Medium.

</comment></comment></comment></comment></comment></comment></comment><comment><USER13> Those coccoliths also make for fantastic oil bearing reservoir rock, provided certain conditions are met, otherwise chalk tends to make a good seal. Some of the most prolific oil fields in the world, in the north sea, come from fractured chalk beds.

For example, massive salt diapirs (think of them as giant, mountain sized fingers) 5-15 miles beneath the earth's surface are gradually squeezed, like a fluid, moving upwards and fracturing rock (and chalk) above, creating porosity and permeability necessary for oil production.

</comment><comment><USER14> Reminds me of a quick, classic read from GK Chesterton: "A Piece of Chalk" [https://www.chesterton.org/a-piece-of- chalk/](https://www.chesterton.org/a-piece-of-chalk/)

</comment><comment><USER15> Also the composition of diatomaceous earth [https://en.m.wikipedia.org/wiki/Diatomaceous_earth](https://en.m.wikipedia.org/wiki/Diatomaceous_earth) which is used in certain types of water filters, like pool filters.

<comment><USER16> In a discussion of the economics of a far future spacefaring human civilization, someone once suggested diatomaceous earth as one of the few raw materials that might be exported from Earth, since it might well not occur anywhere else!

<comment><USER17> Especially since diatomaceous earth is good for preventing infestations of insect-sized organisms without depending on the biochemistry of those organisms.

</comment></comment></comment><comment><USER18> So reading Huxley's lecture, [https://ebooks.adelaide.edu.au/h/huxley/thomas_henry/piece-o...](https://ebooks.adelaide.edu.au/h/huxley/thomas_henry/piece- of-chalk/chapter5.html) are we supposed to understand that chalky places like Dover were the bottom of the sea long long time ago? (He is talking about the mud at the bottom of the ocean having the remains of the same creatures.)

<comment><USER19> > But if the Radiolaria and Diatoms are thus rained upon the bottom of the > sea, from the superficial layer of its waters in which they pass their > lives, it is obviously possible that the Globigerinae may be similarly > derived; and if they were so, it would be much more easy to understand how > they obtain their supply of food than it is at present. Nevertheless, the > positive and negative evidence all points the other way. The skeletons of > the full-grown, deep-sea Globigerinae are so remarkably solid and heavy in > proportion to their surface as to seem little fitted for floating; and, as a > matter of fact, they are not to be found along with the Diatoms and > Radiolaria, in the uppermost stratum of the open ocean.

> It has been observed, again, that the abundance of Globigerinae, in > proportion to other organisms, of like kind, increases with the depth of the > sea; and that deep-water Globigerinae are larger than those which live in > shallower parts of the sea; and such facts negative the supposition that > these organisms have been swept by currents from the shallows into the deeps > of the Atlantic.

> It therefore seems to be hardly doubtful that these wonderful creatures live > and die at the depths in which they are found.

> However, the important points for us are, that the living Globigerinae are > exclusively marine animals, the skeletons of which abound at the bottom of > deep seas; and that there is not a shadow of reason for believing that the > habits of the Globigerinae of the chalk differed from those of the existing > species. But if this be true, there is no escaping the conclusion that the > chalk itself is the dried mud of an ancient deep sea.

</comment></comment><comment><USER20> From the comments in the Twitter thread:

> _Only tangentially relevant, but I love the fact that sand from Normandy > still consists of up to 4% microscopic war materiel from WWII._

</comment><comment><USER21> Looking at some of those pictures gave me a slightly light-headed feeling - the same kind I get when I look at the Hubble ultra deep-field.

</comment><comment><USER22> Newbie here with these types of images. In the image there are spheres and flat discs. I take it the life forms were spherical and flat discs have broken off rather than vice versa? Of course I find it hard to imagine discs forming spheres but at the same time, that sphere doesn't seem single cell to me. Fascinating none the less.

<comment><USER16> > I take it the life forms were spherical and flat discs have broken off

Exactly, yes:

[https://twitter.com/ferrisjabr/status/1023256798470463489](https://twitter.com/ferrisjabr/status/1023256798470463489)

<comment><USER22> Thanks, sorry for the silly question as well, I aggressively block social media on my laptop and only seen the image. Visiting your link on a PC answered all my questions.

</comment></comment></comment><comment><USER23> For those of you enjoy good quality things under a microscope, take a look at [https://www.nikonsmallworld.com/](https://www.nikonsmallworld.com/)

</comment><comment><USER24> the world is so beautiful

</comment><comment><USER25> and to think that most of the space in an atom is vacant. Seems to be a tremendous waste of space. incomprehensible that nature would permit this. surely something must exist in that nothingness where the electron vibrates around the nucleus. and we are blind, deaf, insensate to it.

<comment><USER26> You just said it... the electron is there. At any given moment, the electrons occupy that "empty" space, which means it isn't really empty, but full of electrons. The wave function of the electrons is a "smeared" out geometry which occupies that space, with various probabilities of localizing the electron at any given point. When you touch something and experience mutual electromagnetic repulsion (i.e. what touching actually is) you're very much sensing that. No need to invoke magic and mystery to fill a gap that doesn't exist.

<comment><USER27> That does very much sound like magic. The wave function is in principle just describing the probability of measuring a value, if I recall correctly. What you make of it is but an attractive theory to interpret that wavefunction after the fact. And it's not particularly satisfying. It's completely meaningless that it would have been in all places at once, if in fact, when you look, it's only ever in one place.

<comment><USER26> "When you look" is the key phrase there. When you _measure_ you've perturbed the system and a superposition of probabilities collapses to a single possibility. You can try to ignore the problem, but it keeps cropping up. Take for example the Delayed Choice Quantum Eraser:

[https://pdfs.semanticscholar.org/e4af/e51dd7946512eb14674035...](https://pdfs.semanticscholar.org/e4af/e51dd7946512eb146740356488f25a423aa8.pdf)

<comment><USER27> I am not going to even click that. "superposition of probabilities" is not a real thing, merely a mathematical tool. The definition of probability still involves something that is going to happen. Hey that's amazing, it's the probe-ability.

edit: It's very hard for people to admit we really don't know, is what I am trying to say. I mean that's the real definition of chance, we don't know for certain. Whereas, if there is more to the field theories, more than ether, I'd really like to know, but I'm not holding my breath. Between measurement uncertainty and observer uncertainty, the models will remain just that.

<comment><USER26> Well you're allowed to believe whatever you want of course, however divorced from observation, experiment and theory it happens to be. I would just caution you against drawing such strong conclusions about a field you seem to know very little about based on what you think should be, or your intuition.

<comment><USER28> Well, now I read the paper and, while I do find it interesting but don't follow the formulas, I wonder what you are trying to show me.

Removing the Beamsplitter (BSA) would only remove the ability to correlate the measurements, so how do you know that there are actually no instances of Gaussian distribution happening already at the origin, which would cause the fork at the splitter (instead of information traveling back in time, for example)?

> observation, experiment and theory

we agree on the observation and theory parts. The predictive power of the theory for experiments is duly noted, but here the object under scrutiny is way bigger than a single atom. Whereas the science around the materials used, crystallography to begin with, is way above my grade.

The language in the paper caused me a bit of trouble: " _It is easy to see ..._ ", " _at the same time_ ", " _a quantum_ ".

</comment></comment></comment></comment></comment></comment></comment><comment><USER29> Aww, I was gearing up for learning about blackboard chalk.

</comment><comment><USER30> When elon musk says it's possible that we're living in a simulation, it's fun to think about the computer that can handle this level of detail and complexity from the very minute to the billions of galaxies

<comment><USER31> And then it's funny to realize a simulation would not have to compute those details until someone looks at them.

<comment><USER30> You're definitely right about that! But who is that someone? A human, a bateria, any sentient being?

<comment><USER32> You.

<comment><USER33> Me. Who else ?

<comment><USER34> Not you, you're part of the simulation. It's just superasn, Elon Musk, and a bunch of goldfish used to generate entropy.</comment></comment></comment></comment></comment></comment>


No alcohol safe to drink, global study confirms (2018) - <AUTHOR> https://www.bbc.com/news/health-45283401 <comment> just-juan-post I have to wear a mask to protect others from Coronavirus so I don't kill others and for the general safety of the larger population.

We need to ban alcohol for the same reason.</comment>


The man who made 'the worst video game in history' (2016) - <AUTHOR> https://www.bbc.com/news/magazine-35560458 <comment><USER2> The BBC should have titled this article "The company that made the worst video game".

As it reads, it was not the developer's choice to crank out a title in a fraction of the time of the usual project - especially on a platform that cannot be patched like modern games.

Yes, he accepted the deadline, but when management is obviously aware of the risks imposed by time, the failure is the responsibility of more than just the coder:

> "There was a manager who was assigned to make sure I was eating so that I'd > be able to keep going."

</comment><comment><USER3> and someone fixed ET years later.

[http://www.neocomputer.org/projects/et/](http://www.neocomputer.org/projects/et/)</comment>


Lodsys fiercely opposes Apple's motion for an intervention  - <AUTHOR> http://fosspatents.blogspot.com/2011/07/lodsys-fiercely-opposes-apples-motion.html

<comment><USER2> Well, they had to. So this means they did what was expected and Apple can move to the next step, but Lodsys is showing real savvy as a litigator, meaning that they didn't hire inexperienced people. They must have a well funded company backing them, probably similar to SCO's relationship with Microsoft. Personally, I don't see any other reason a company with no products, no market and no history could exist except as a proxy for pursuing the market interests of a shadow player. Even if all the companies being sued pay .57% of gross per infringement, how else could Lodsys get the capital needed for the overhead of all the lawyers needed to file and pursue these cases simultaneously.

On a side note, does anyone have a business model for a "Troll-Bait" company?</comment>


Notes on Category Theory with examples from basic mathematics - <AUTHOR> https://arxiv.org/abs/1912.10642 <comment><AUTHOR> This beginner-friendly resource was mentioned in the ACT 2020 pre-conference tutorial yesterday.

See [https://www.youtube.com/playlist?list=PLCOXjXDLt3pYPE63bVbsV...](https://www.youtube.com/playlist?list=PLCOXjXDLt3pYPE63bVbsVfA41_wa3sZOh) for video recordings of all the tutorials, which were are all excellent. Highly recommended for anyone interested in abstract nonsense ;)</comment>


Drafting Only Men for the Military Is Unconstitutional, Judge Rules - <AUTHOR> https://www.nytimes.com/2019/02/24/us/military-draft-men-unconstitutional.html <comment><USER2> We haven't had the draft since 1973. What's in question is _registration for the draft_ in case we ever decide we should need it again. I think this is largely a moot point, since we're well into the information age, and identifying all American citizens of a draftable age is likely pretty easy whether they are registered or not.

<comment><USER3> I suppose the draft doesn't necessarily have to be for military service for a war with other countries.

For example, if we learned that something large was on a collision course for the earth, we might have years to prepare to deflect it, or to build shelters, or something along those lines, but I can absolutely see a mobilization being necessary.

Of course, there's no legitimate reason why we'd mobilize men and not women.

<comment><USER4> There is no legitimate reason to draft anyone.

People aren't your slave. It doesn't matter that there might bad consequences if there is something 'to be done'.

If you don't respect human beings as individuals in the first place, we already lost.

<comment><USER3> If you mean unpaid labor, then that's not how drafts work, but I'll assume you mean forced labor.

I've seen the same argument used regarding taxation.

I'd argue that people have duties and obligations to their government, just as a government has duties and obligations to it's citizens.

So I absolutely believe that the government has a right draft people to defend the country. Drafting people just to wage war to advance our interests I have a lot more qualms about.

<comment><USER5> Do you think slavery is fine then? If compelled labour in the military is permissible by you because people have 'obligations' to the government? What is a government except as an entity to ensure people's natural rights are not infringed. And we are somehow obligated to be slaves to this entity?

<comment><USER3> I understand there may be a need for compelled labor by the government, in a time of war or national emergency.

Am I okay with it?

I think that depends on whether it's a defensive war or a real national emergency. China invades, or yellow stone's super volcano erupts, yeah, those are legitimate reasons to force humans to cooperate, because survival is at stake. Vietnam type situations, or the Border Wall thing... I'd be protesting a draft.

U.S. law and supreme court precedent both say that a draft is not slavery, but I understand your opinion, or definition of slavery, may differ.

I also believe quarantine laws for infectious people are valid, that police should be able to arrest violent criminals, etc. Basically, I believe if your actions or failure to act endangers the health and well-being of others, then the government has a legitimate interest in compelling or restricting behavior.

Most people would consider providing for the national defense and preserving the lives of citizens to be part of what a government does.

<comment><USER5> >preserving the lives of citizens

this is completely false. a war is never about killing citizens but about imposing political will. without a defense, the occupier would simply impose their political system on the occupied. a government, being a political entity, is only forcing people to DIE so they can maintain their political hegemony over some people.

<comment><USER6> That's just false, since a lot of times political will involves killing civilians. For example: Stalin, Mao, Andrew Jackson

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER7> There have been several wars where the slaughter of men was so extreme that the countries involved would have collapsed if the women were slaughtered as well, because the population could not have rebounded.

I heard long ago (sorry, no reference) that the average French soldier was a couple inches shorter in WW2 than in WW1, which was attributed to the male slaughter (though I suspect that food shortages were a more likely cause).

In France and Germany, after WW1 and WW2, it became commonplace for the women to marry foreigners and old men. I don't know if that happened in Britain as well.

Baby booms are common after the end of terrible wars. I read once that people were copulating in the streets of London after the WW1 armistice was declared.

<comment><USER8> How would that work? If there were 80 women left and only 20 men would the expectation really be that the remaining men knock up 4 women each? That doesn't seem like it would ever fit our social norms and seems like a completely unimportant point.

<comment><USER9> In 1871, only 12% of Paraguayans were male due to massive losses in war. Women were happy to share men in order to have babies.

[https://www.reddit.com/r/AskHistorians/comments/9hg68w/in_18...](https://www.reddit.com/r/AskHistorians/comments/9hg68w/in_1871_only_about_12_of_paraguayans_were_male/)

<comment><USER10> > _Women were happy to share men in order to have babies._

That not supported by your source.

<comment><USER9> My answer is perhaps too facetious, but I think mostly supported by the link. In particular:

 _So, what about dating? It 's not difficult to see a continuation of pre-war Paraguayan society in this regard. Back then, there were less men than women. After the war, this was still the case. Women were still commonly the head of the family and births out of wedlock were a common occurrence, something that was also the case in the pre-war society._

There is essentially no research into the exact numbers and status of these children born out of wedlock. All that's really known is there was essentially no stigma at this time due to being born out of wedlock:

 _This is unfortunately where, as Pottshast herself points out, documentation fails us. We don 't know. In fact, the documentation in general considering how many of these children were born is not entirely known. With the mother being the identifiable stable force in the family, it seems that identity was tied to the mother rather than the father as in the case of children born out of wedlock. A lack of stigma could therefore be seen as a continuation of pre- war Paraguayan society._

</comment></comment></comment></comment></comment><comment><USER11> Equal rights mean equal opportunity and equal responsibility.

<comment><USER12> I do share this "equality" sentiment, but I think there's a valid counterpoint in that only women assume the risks and responsibility of pregnancy and childbirth. Society depends on women putting their bodies on the line to produce more members of society. There quite simply _isn 't_ a way to equalize this burden between the sexes for the foreseeable future. Some people see a male-only draft as a means to artificially balance this biological inequality.

EDIT: Point out another group's reasoning that hasn't been mentioned yet, get downvoted. ???

For all the "forced impregnation" replies, forced impregnation isn't analogous to the draft. The draft and pregnancy are fundamentally different things that can't be made equivalent. The argument being cited here never implied that this would be an equivalent exchange. It's not.

<comment><USER11> I would be fine with pregnancy & child-rearing responsibilities being a valid reason to avoid the draft.

Of course, in the interest of equality, both parents would be eligible for the child-rearing exemption but only one parent would be allowed to claim it.

<comment><USER12> In some ways, the reasoning I cited above might simply be shortcutting a system like what you've described (via binning by biological sex). Simpler rules, but less comprehensive.

<comment><USER11> But once the child is born, their is little reason the parent who gave birth to be the one to provide care. It should be the family's decision who gets the post-birth exemption.

<comment><USER12> I think that makes sense for the average case. How would you work this out for divorced couples with shared custody? Also, any consideration for stuff like breastfeeding? In times of war, formula could become scarce.

</comment></comment></comment></comment></comment></comment><comment><USER13> People here are mixing up the concepts of registering for the draft vs actually having a draft. Ending the SSS would just eliminate the registry, NOT the possibility of a future draft. Conscription has already been ruled constitutional, and there are a million better ways for the government to look you up today than a partially complete registry of where some people lived when they were 18.

</comment><comment><USER14> Ending the Selective Service System is certainly an option. It's unlikely the US will need a mass draft any time soon, and if it did need to draft young people (or just men) in large numbers, it wouldn't be all that difficult to assemble lists of them through other records. Just use high-school records, or drivers licenses or census lists.

</comment><comment><USER15> Perhaps it's unconstitutional, but there are biological reasons why across all cultures throughout history (as far as I'm aware) men are the ones who are sent to war.

Maybe I'm old fashioned, but the idea of being okay with sending my mother, or daughter onto the battle field is more unethical than treating the different sexes as if they have biological differences.

If women want to apply, then fine, but I do worry about a society whos men are willing to send their women to war.

<comment><USER16> I worry about a society that sends anyone to war. Its completely unethical no matter who it is you send.

<comment><USER17> What would you would do if you were attacked by another country? What if your peaceful trade partner was being attacked? What if there were a genocide occurring in another country?

<comment><USER16> What are the reasons to attack? Mainly for resources and religion. Resources was solved by better global trade, religion is mainly in decline.

>What if there were a genocide occurring in another country?

How does a military solve this? Create an even bigger genocide?

<comment><USER18> I would think a military solves a genocide by preventing it. Reading the news or history would provide many examples of genocide being stopped by military action.

</comment></comment></comment></comment></comment><comment><USER19> Vaguely related question. Should a draft begin, and you're not keen on shipping out to the front lines. What could you do to avoid that that isn't illegal? Say I have a lot of experience in something that I would think the military would make better use of like ML. Is the move to sign up pre emptively to do that? Or would you assume to be assigned to such a role if capable?

<comment><USER20> Be the average american male who is too fat and medicated to serve, or be in a skilled job that is important to the war effort.

Do keep in mind that 90% of the jobs in the military aren't fighting on the front lines so chances are, you would be some support clerk.

<comment><USER21> Poor vision, as well, is becoming a serious problem for recruitment.

</comment></comment></comment><comment><USER22> I'm amazed at how naive a lot of the comments in this thread are. You can hop over to other corners of HN or Reddit and you have people convinced that WWIII is around the corner, or the rise of China is going to lead to a hot conflict in the Pacific again, or that migration and refugee crises will continue to dominate political discourse and cause other security problems. I don't think it's controversial to state that we've returned to the regular flow of history and Great Power conflict.

But a lot of what I'm seeing here amounts to discounting the importance of this because the "likelihood" of a draft is low, or the usual (wrongheaded) arguments about how because the percentage of people in the military who actually fight is low, so adding women to selective service requirements isn't a big deal. Serious countries don't think like this - especially a country that, allegedly, is supposed to shoulder most of the global security responsibility. You don't get to make hand waivey dismissals and still expect peak performance from these huge complex organizations, nor do we get to put off thinking about it because we think an event like WWIII is "unlikely for a while". On what time horizon does it have to be "likely" for us to have to actually engage with it? 50 years? 20? 10?

I don't think we've thought deeply enough about this at all, and frankly I don't view the prospect of my daughter or sister being drafted into a war as "progress".

<comment><USER23> > I don't view the prospect of my daughter or sister being drafted into a war > as "progress"

Neither is the prospect of only drafting men.

</comment></comment><comment><USER24> There was one occasion in my life where Selective Service registration mattered. I applied for a 911 operator job for a large urban county and it was a question on one of the many stacks of application paperwork. It was on a questionnaire with others like have you ever used marijuana, have you ever lied to your parents, how many traffic tickets have you received.

Most of a year later, after a detailed background investigation that included questioning old friends and people in the neighborhood, they offered me the job. Can't prove it, but I got the feeling they wouldn't have unless I had registered for the draft, denied smoking pot, etc. The registration record was used as a test for lawfulness by that law enforcement agency.

Ladies, you might want to keep that in mind if you think you might ever want a government job or a security clearance. Your choice will be remembered.

<comment><USER25> Most likely it's not just a test. Even though it's a county government job, the Feds probably made it a requirement to receive federal funds so it's enforced on state/county/city levels too.

</comment></comment><comment><USER26> The USA should use this opportunity to step back and re-think whether registering for the draft is needed in this age. The whole draft registration program is simply a waste of millions of dollars a year.

</comment><comment><USER27> This pretty much guarantees we'll never have a draft in America again for bullshit reasons like Vietnam if it's upheld by the Supreme Court.

</comment><comment><USER28> Drones and robots fight the future wars.

</comment><comment><USER29> Mandatory military service would alleviate so many social problems in the US.

* people from different backgrounds and walks of life would live and work together at least once in their lives.

* people would recevie excercise and discipline training at it's most basic form.

* there wouldn't be a caste of people that serve in the military from one generation to the next.

* a lot more people would be exposed to the world outside of the US

* exposure to different types of work and training opportunities can alleviate labor shortage issues.

* last but not least, unity! America is dying as a result of extreme social fragmentation. I'd bet a lot less people would see issues as affecting the country as a whole as opposed to their "tribe" this way.

Look at how the society is in countries with mandatory military service (S. Korea,Switzerland to name two)

<comment><USER30> [https://en.wikipedia.org/wiki/Conscription](https://en.wikipedia.org/wiki/Conscription)

The majority of the developed world has no mandatory service, and "look at the society" in all of those places, many of which border Switzerland that you mentioned as an exemplar. Are Iceland, the Netherlands, or Canada violent hellholes of tribal insularity? No, and they didn't need conscription. Meanwhile there are plenty of horrible places with mandatory conscription, per the maps on Wikipedia.

You can't magically make people love each other by putting them in proximity or the middle east would not currently be on fire.

Particularly in America, mandatory conscription would be a fantastic way to get people to resent the government more than they already do, which is probably currently at an all-time high.

Finally, you go serve if you want to, but it's tyranny to tell other people what they have to do, esp. when you're talking about many months or years of their life. What's next, mandatory church? Wouldn't that also be great for society, according to some opinions. Church attendance, also, is extremely high in South Korea, are you sure it's the conscription and not the Church responsible for the society you admire?

<comment><USER31> Your comparisons are all off.

Iceland, the Netherlands, and Canada are much smaller and more homogenous than the US which greatly reduces tribalism. And proximity alone isn't the point, it's about working together and sharing a higher purpose while learning discipline, teamwork, leadership and other valuable social skills.

There's also a massive difference between church vs state. Serving your nation isn't exactly a high price for the privilege of being born in the US.

<comment><USER30> There aren't any diverse, developed nations of 330 million to compare to so I used the nearest proxy.

Ah yes, the great privilege of no healthcare, stagnant wages, the worlds highest incarceration rate, and largely nonexistent public transportation... and I'm to pay for this privilege with mandatory military service and perhaps cast carelessly to my death with no say in the matter.

Strong sales pitch. If I don't like it, it'll cost me over two months of minimum wage to file the paper to renounce my citizenship.

That's tyranny. If it were such a privilege, conscription would not be necessary, since people would join up for their great nation that they love and that loves them back. That's not where we are, though, is it?

Lastly, I mentioned the church because it's yet another thing some people think ought to be mandatory for the good of society.

Everybody has an opinion about what everybody else ought to be doing.

<comment><USER31> They don't work as proxies when they're so different.

Healthcare is available. Incarceration rate won't affect you if you're not a criminal. Wages are the only serious issue and more related to global trade and changing industries than any country-specific policy. There are far worse conditions in other countries but my experience has shown people who list these complaints usually do not have any understanding of the plight of billions of poor around the world.

Nobody likes to pay taxes either and won't willing do so if we didn't have laws and enforcement, but it's obvious that it's needed and positive.

Yes, everybody has opinions. That's irrelevant to this discussion. If you really don't like staying in this country though, please do leave. Why would you stay? There are plenty of ways to raise the funds to move and renounce your citizenship, ironically many of which are way harder in other countries.

<comment><USER30> Healthcare is available, yes, and so are gold-plated Lamborghinis -- these both apply to a certain class (not the same class, mind you, but there is an economic floor here).

Minimum wage is about $1300/mo, good luck paying rent and health insurance with that and not starving. Good luck paying rent and food and power on double that income and still being able to afford even remotely decent health insurance.

As for incarceration...

When everything is a crime, everyone is a criminal. Famous lawyers are writing books about that. [https://www.amazon.com/Three-Felonies-Day-Target- Innocent/dp...](https://www.amazon.com/Three-Felonies-Day-Target- Innocent/dp/1594035229)

If you don't think just about everything is a crime, then you're uninformed. You probably committed a felony when you violated a website TOS today.

I have no problem with taxation as a concept.

Everyone says "if you don't like it leave", but that's a bluff -- until 2010, it was free to renounce your citizenship, and in 2010 it became $450. Four years later, it became $2350. If more people leave, it'll go up again. We say it, but we're afraid of people actually doing it.

I won't renounce my citizenship, but I do think it's silly for us to pretend we want people to do it when we provably don't.

<comment><USER31> You are stretching everything to such absurd levels that you effectively have no argument. Not everything is a crime and enforcement makes all the difference.

Nobody is afraid of people leaving the country famous for individual liberty, it's just administrative cost. You're attributing another reason without any evidence. And really, why blame the fees as if that's what's really keeping you here. Get your visa, move your stuff, and then worry about the renouncing when it matters.

Perhaps we can have free and automatic citizenship renunciation and revocation for failure to register for service, would you take that deal?

</comment></comment></comment></comment></comment></comment></comment><comment><USER32> It is lamentable that we have come to devalue gender in the name of equality. An army of women will lose and that is independent of wanting equality for women.

</comment><comment><USER33> How about getting rid of draft altogether?

<comment><USER34> That is simply impossible. We've been at peace for a long time, but one day war will break out, and not enough people will join the military voluntarily.

<comment><USER35> If there's not enough volunteers then pay them more. Conscription is slavery.

<comment><USER36> Nail on the head here. The US increases the military budget year over year yet soldiers pay does not increase.

Instead the president looks to raid funding for military housing for his own boondoggle.

</comment></comment></comment></comment><comment><USER37> Compulsory service across the board has always seemed more appropriate to me.

It would help with the lack of discipline in the civilian population, while engendering a better understanding and appreciation for the realities of combat and war.

On the military side I think it'd add some much needed diversity and perspective to a group dominated currently by "America, Fuck Yeah!" types who volunteered to go kill people and blow things up.</comment>


Picthing bloggers with this email, got no reply. Advice needed.  - <AUTHOR>

Pitched bloggers with the email below but no one replied. Am i doing it right? Advice pls<p>Hello,
   I am Samuel, CEO of Adclays Advertising. Adclays is a system built for publishers to sell ad spaces directly to advertisers with the industry lowest fee of 15% and it gives more control to the publishers. Publishers can choose between CPM or tenancy pricing and have total control of their zone. We are currently in Beta and need users to test our system. We currently have some publishers using the system. Beta users would use the site for free without fees and would get other incentives when we launch.
  You can check out the website and our press kit at: http://adclays.com/company/press/kit.php If you have any questions, please mail me. Looking forward to hearing from you. Thanks. <comment><USER2> This just reeks of sales pitch. I've been blogging for six years. I've got some adsense on my blog ( <http://www.puremango.co.uk> ) but I don't relate to that jargon about publishers, ad spaces, industry lowest fees. It's a hobby not a business. WTF is tenancy pricing? I have a zone?

Use something more like this instead:

Hi Howard,

Really enjoying your blog. I see you're running adsense at the moment. I'd really appreciate some comments from you on my advertising system. If you're interested I'll set you up with a free beta account. You don't have to commit to putting our ads on your blog, I really just want some feedback from quality bloggers who understand advertising.

Let me know if that sounds like something you'd be interested in.

Thanks, Samuel, founder of Adclays.

<comment><USER2> PS: Ok, it's been ten hours. You should have emailed me to invite me to your beta program. I'm your target market and I've shown interest and a willingness to provide feedback. Isn't that exactly what you want? Why aren't you chasing me up?

<comment><AUTHOR> Hello, thanks for the reply and advice. I was really busy today so couldn't check HN until now. I would definitely send you an email soon.

<comment><USER2> no worries :) I've had a busy day too. I should have waited longer before poking you! I got your email, will reply tomorrow. Thanks!

</comment></comment></comment></comment><comment><USER3> Sigh....I get these all the time, and delete right away.

This is all about you, your company, why you're so great.

What about me? I'm a blogger. Bloggers have egos. Play to my ego, at least try to give me the sense that you spent at least 5 minutes getting to know something about me.

Who are the publishers using the system? Why not list them.

Stop talking about yourself, talk about me, write a blog post and link to me, then maybe you'll have a shot.

Bloggers you don't have any previous relationship with are tough nuts to crack.

Good luck.

<comment><USER4> yeah - at the very least try and customize the letter to the particular person. Otherwise you're just spam.

</comment></comment><comment><USER5> Wow, that seriously sounds like SPAM!

Be human man, you are writing to a blogger.

Being a blogger, I'd never ever respond not ever read beyond first line.

Make it sounds cool man. And you are not "CEO", are you? You are a "Founder" If I am not wrong.

Tell me what is in there for "me" rest is bullshit.

<comment><AUTHOR> Thanks for the advice, i tried to keep it short. Do you think writing the benefits as a sentence or bullet points?

</comment></comment><comment><USER6> It's not awful, but as user24 says - it's VERY salesy.

Think about what the problem is for a blogger - making some money out of their hobby, in the easiest possible way, without annoying their readers.

If you are not a blogger yourself, why not interview blogger friends to see what the issues or problems that they are having either with making money or with using tools (not getting paid etc.)

And yeah, don't say CEO - and use language your mother and father would understand - I know some bloggers are technical - but many are not.

Good luck ;) - (and spelling error in your title BTW)

</comment><comment><USER7> You're going to need to relate to the people you're writing to. Bloggers are individuals, not commodities. Pitch to solve their problems -- if they're bitching about a problem your product could solve, for example, connect the dots for them.

Look at it like this: what you've sent is like the junk mail I throw out each day — it's for everyone, so I know it's not for me. I'd never toss a hand written, hand addressed letter sent to me, though. Create the same distinction in your email, make it clearly for whomever is receiving it, and you'll at least escape the trash a little longer.

</comment><comment><USER8> It's good. Keep going.</comment>


Who need XSS when you can simply ask? - <AUTHOR> http://www.reddit.com/r/programming/comments/9oj39/javascript_in_a_single_picture_seen_on_a/ <comment><USER3> Summary (it is all a little meta for me): the reddit link above started as a fairly innocuous reddit thread comparing the sizes of the two books "Javascript - The Definitive Guide" and "Javascript - The Good Parts" - <USER2> Good Parts being a good deal smaller as the linked photograph illustrates.

Some wise guy decided to have a little joke, and posted a comment instructing people to copy and paste a snippet of Javascript on their URL location bar. A _lot_ of people (presumably "web programmers") did as instructed. That little snippet posts a comment on that same thread, instructing the next person to do the same. That entire reddit thread is overrun with those script generated comments.

Social lesson: we are f __ked as far as security is concerned, if that reddit thread is any indication: even programmers would sheep-like do as they are instructed. I suppose that was the "lesson" the wise guy had in mind.

Some good samaritan posted another Javascript snippet to clean up the reddit thread - automatically downvote the spam comments or hide them.

<comment><USER4> I would have to assume that people knew better, knew what it would do, and ran the JS anyways as a joke.

<comment><USER5> You do, of course, know the problem with assuming?

(And Ming can be merciless about such things)

</comment></comment></comment><comment><USER6> This is an excellent illustration of a core principle of security: anything relying on "educate the user so that they know better" is doomed to failure.

<comment><USER7> To be precise, _anything relying on "educate the user so that they know better" is doomed to be insecure._ It is likely to be successful in the sense of becoming popular because it offers humans someone else to blame.

For example, if I am in IT and I tell people to choose a 512 character password with alphanumeric characters that changes every day and doesn't repeat any sequence that appeared in a previous password or contain a dictionary word, I can expect people to write their passwords down on paper and get hacked, even if I tell them not to write it down.

But I can always blame them for writing them down, few people will blame me for being too lazy to find another way to secure the system.

<comment><USER8> In most cases, users will either:

1\. Choose a memorable (read: simple, dictionary, insecure) password

2\. Choose a good password and write it down

If Joe the Cubedweller writes his login password down on a sticky note, the only other people who are expected to have physical access to that note are him and the other cubedwellers, and they're going to have little to gain from seeing it. I would be much more concerned with Joe picking a bad password that could be guessed by an attacker on the outside.

<comment><USER9> Memorable passwords don't need to be simple, dictionary, or insecure.

MySonPlaysLittleLeague is a password that someone can easily remember, but few people get pointed in the direction of good sentence passwords, and most password policies indirectly limit the use of sentence passwords with character limits or number and punctuation requirements.

<comment><USER5> My favourite technique isn't to make the sentence itself the password, but the first letter of each word (with some punctuation thrown in for good measure). E.g. pick a line or two from a song, like "All the fear has left me now / I'm not frightened anymore" and that becomes "atfhlmn-infa" (if it's something that insists on digits too then you can easily do a substitution like "atfhlmn-1nfa"). Memorable without being insecure.

</comment></comment></comment></comment></comment><comment><USER10> Makes you wonder how many popular websites are using code snippets copied and pasted verbatim from the web.

</comment><comment><USER11> Excellent! Took me a while to work out what was going on there. I'm going to blame it on the apparent removal of the comment that started it though.

<comment><USER12> For others: scroll to the lower part of the page.

<comment><USER13> When I viewed it there were about 50 spammed comments. That was a cute worm attack. ;)

</comment></comment></comment><comment><USER14> "Given a choice between dancing pigs and security, users will pick dancing pigs every time." - Edward Felten and Gary McGraw

</comment><comment><USER15> It's gotten worse in the last hour or so. Someone's modified the worm so that simply looking at a page with the comment will cause you to start replying to all the posts on that page. Coupled with the fact that reddit has the "red/orange envelope" feature, whereby users are notified if somebody replies to their posts, and the fact that users tend to watch for said envelope in anticipation, the site seems to be melting down.

<comment><USER16> It's actually when they mouseover any link, and it's mostly thanks to a nasty bug in the Python markdown implementation.

</comment></comment><comment><USER17> "Javascipt The Good Parts" is to the Rhino book what "The Little Lisper" is to the hyperspec.

<comment><USER18> The rhino book is still an invaluable reference.

I own both, I've read both, but the rhino book is the one sitting on my desk 24x7.

<comment><USER17> No Common Lisper can live without the Hyperspec; it doesn't sit on our desks but its content is interwoven with every Lisp IDE and with SLIME.

</comment></comment></comment><comment><USER19> At first I thought it was the picture that was causing all those posts because I didn't think people were really dumb enough to paste javascript in their browser when they don't even know what it does (especially on the programming reddit...)

Way to prove my belief wrong!

<comment><USER4> Probably many knew what it would do, so that's why they ran it, as a prank/joke.

</comment></comment><comment><USER20> Reminds me of the save this picture as foo.js shit bricks attacks on 4chan.</comment>


A Critique of Rust's `std::collections` - <AUTHOR> http://ticki.github.io/blog/horrible/ <comment><USER2> Yes, you really do need collision attack resistance in your standard hash table implementation. You know why? Because we've known for a long time that insecure defaults are broken. I'm glad rust makes the correct choice here.

<comment><USER3> No, cryptographic hash has an additional property. It is one way. So, given a hash it is hard to derive original input.

Collision resistance is a separate property which can be fulfilled without one way property.

Maybe you want hash numbers that are not predictable by an attacker, but sip hash is not salted either. Plus salting does not require a cryptographic hash either.

<comment><USER4> >It is one way. So, given a hash it is hard to derive original input.

This is the definition of a Hash Function. Not a cryptographic Hash Function.

Cryptographic Hashes should __NEVER __collide, on any inputs, ever, period. The moment it is found too, the algorithm is considered depreciated. This is why MD5 shouldn 't be used anymore, there is a generalized algorithm for producing collisions.

Cryptographic hashes are overkill for HashTables/HashMaps because you can't use 128/256/512bit address spaces unless your attempt to store all the information in the galaxy or observable universe. And modern computers just aren't there yet. Also they are very slow.

So when your masking a 512bit output, down to 16bits of your HashTable you just lose the _will never collide_ guarantee. Then something that operates at 10GB/s, and _can collide_ sounds better then something that runs at 150MB/s and _will still collide anyways_.

<comment><USER5> >This is the definition of a Hash Function. Not a cryptographic Hash Function.

No, a hash function is just any function which can be used to put values into a hash map. If your inputs are numbers, modulo will work fine as a hash function, but is obviously not one-way.

>Cryptographic Hashes should NEVER collide, on any inputs, ever, period.

This is obviously not possible, as the output of the cryptographic hash function is of fixed-length while the input is variable-length. Finding collision just needs to be hard, not impossible.

<comment><USER6> How is modulo invertible in the general case? If it is, can you demonstrate? I have picked certain numbers and their values modulo 10 are 6, 7, and 8. What numbers did I pick?

<comment><USER7> It doesn't have to be. Onewayness says nothing about finding "the original x". If a function is one-way, it means that given y (a random n-bit string in the output space of h), it is hard to find any x such that h(x) = y. If your h() is just a modulo operation, this is trivial: just choose x = y.

<comment><USER8> Ah, I see, way as in _path_ , not way as in _direction_ (which is I think the misinterpretation that leads people to the root of the misunderstanding). So, there's one path to get from x -> y, but it does not imply you can't get back to the original x. In that respect, "way" is an unfortunate word to use, at least as it's used in modern English.

</comment></comment></comment></comment></comment></comment></comment><comment><USER9> Does Rust define collection traits for abstract interfaces like Set, Map, and Queue like Java's Collections interfaces? I don't see any in the std::collections documentation. Standardizing those APIs in the std lib seems as (or more!) important than providing concrete implementations like BTreeMap. I see some 2015 discussion about missing collections traits:

[https://internals.rust-lang.org/t/collection-traits- take-2/1...](https://internals.rust-lang.org/t/collection-traits-take-2/1272)

[https://internals.rust-lang.org/t/traits-that-should-be- in-s...](https://internals.rust-lang.org/t/traits-that-should-be-in-std-but- arent/3002)

For comparison, here are Java's core collection interfaces: Collection, Set, SortedSet, List, Queue, Deque, Map, and SortedMap.

[http://docs.oracle.com/javase/tutorial/collections/interface...](http://docs.oracle.com/javase/tutorial/collections/interfaces/index.html)

<comment><USER10> IIRC, we need higher kinded types before we can create a truly great set of generic collections traits.

<comment><USER11> I'm curious about why higher-kinded types are needed for this. I'd have thought that it would be possible to create these kinds of traits in rust's current type system. Is there someplace I could read more explanation on this?

<comment><USER10> [https://github.com/rust- lang/rfcs/blob/4b4fd5146c04c9c284094...](https://github.com/rust- lang/rfcs/blob/4b4fd5146c04c9c284094aad8f54ca5c2093c7f2/text/0235-collections- conventions.md#removing-the-traits)

</comment></comment></comment></comment><comment><USER12> This showed up on r/rust last night and there's a lot of discussion there:

[https://www.reddit.com/r/rust/comments/52grcl/rusts_stdcolle...](https://www.reddit.com/r/rust/comments/52grcl/rusts_stdcollections_is_absolutely_horrible/)

</comment><comment><USER13> A lot of this article might be a matter of opinion, but the discussion on HashMaps seems to be outright false. The author has set up some kind of a double hashing strawman, when the actual implementation uses linear probing (which is the only kind of Robin Hood hash table anyone would implement today).

</comment><comment><USER14> > And, ignoring that point for a moment, The idea that your code is 'secure by > default' is a dangerous one and promotes ignorance about security. You code > is not secure by default

Bah. This argument can be used to show anything. I could argue that C++ is better than Rust with the same argument.

</comment><comment><USER15> I'm not entirely sure I get all of these arguments. It sounds like someone complaining about the language being young, and the early implementations aren't perfect.

For not being perfect, it's amazing how awesome the std lib is!

Also, the concurrent collections didn't show up in Java until 1.5, I believe. I think that was ten years into the life of the language, which was after the 1.3/4 releases which actually made the JVM substantially more performant.

Rust is young, concurrent data models are hard, but it is being worked on, and you can lend a hand! There are good points in this article, and some of them are being discussed on the Rust forums. This is a great time to be involved in helping shape a language and its libraries!

<comment><USER16> I strongly believe that concurrent datastructures should be kept out of the stdlib. There are just way too many tradeoffs to worry about here, and these tradeoffs are far more important in the concurrent case.

Take a concurrent hashmap for example. Do you want a "vec of lock free lists" kind which is lock free and infinite-capacity (no need to copy-reallocate), or do you want a probing one which has fine-grained locks and needs to reallocate (but has better cache behavior)? Or something in between? If it matters enough that `Mutex<HashMap<K,V>>` isn't good enough, then these tradeoffs matter too. Rust could have a rogues' gallery of concurrent hashmaps, but that feels like bloat.

Some already exist in the ecosystem, though, and you can always use those. But I'd love to see more work here!

Having a semi-official/nursery library containing a lot of concurrent datastructures would be nice, though. crossbeam provides better primitives for writing such things, but not the actual datastructures.

<comment><USER17> Disagree.

There are tradeoffs in non-concurrent data structures too. Do you want a boolean vector that aligns to word size, or one that conserves memory and fits in cache? Pushed to the limit, nearly ever non-primitive part of the library has compromises.

Don't let great be the enemy of good. Concurrent collections are a common need. Include some reasonable implementations with compromises. No, you won't answer every use case, but you can be better than `Mutex<HashMap<K,V>>` and still provide something solid.

<comment><USER16> Sure, there are tradeoffs everywhere, but there's a distinction here. I'm talking about things which can be cobbled together for most use cases from what already exists in the stdlib. Vec<bool> is good enough for most use cases, and thus BitVec doesn't exist in the stdlib. Mutex<HashMap> is also good enough for many use cases. The better, more specific implementations exist as separate crates.

Need a concurrent hashmap? Use Mutex<HashMap>. Think that's not good enough for your use case? Then what the stdlib would have offered will probably not fit for you either.

Remember, I'm not saying that we shouldn't have these things in a library somewhere (even an official library), I'm saying they shouldn't be in the stdlib, because there's an additional burden to that, and stability guarantees mean that it's harder to evolve.

</comment></comment></comment></comment><comment><USER18> This particular quote rang _very_ true to me:

> If the allocation is hidden to the programmer, she might not realize the > expensive operations behind the scenes.

I am a green Rust programmer, and I currently have little insight into the allocation costs of the various things I'm doing, and I haven't yet found a strategy for gaining it. I feel like the actual mechanisms for memory management are _so_ deeply buried that it would take lots and lots of spelunking to get an idea of what's going on behind the scenes. Even something as simple as a "This function allocates <x> memory" tag with stdlib functions would help me immensely.

<comment><USER19> I agree that we should add some more documentation in this area (though we always have to be careful that we don't document things so thoroughly that we de-facto stabilize the internals and make it impossible for us to improve them in the future). But in the meantime, if you're just learning the language, I would recommend not being overly concerned with the performance details of collections until you start seeing them at the top of your performance profiles.

EDIT: And of course, I do encourage you to check out the documentation that we have in the std::collections module that goes into at least a little detail about each of the standard collections, along with tips for choosing when to use each: [https://doc.rust-lang.org/std/collections/#when-should- you-u...](https://doc.rust-lang.org/std/collections/#when-should-you-use- which-collection)

<comment><USER18> Well, it's not so much about performance of existing code as it is about being able to take a high-level view of the design of a program. To pick a bad example, if I know one function will allocate memory according to a certain pattern (e.g. 2n*sizeof(obj)) and another will just shift an internal pointer around, I predict it'll get easier to reason about the behavior of the code. The semantics of ?alloc+free are exceptionally easy to understand, but I have no idea how or when Rust allocates memory, except for a vague notion of heap vs stack. I suspect there's an elegant relationship between how Rust does its (hidden) memory management and the behavior of the borrow checker, but I haven't come across anything yet linking the two concepts.

Mostly, I think my problem is that I don't know what I don't know. Like I said, I'm green. :)

</comment></comment></comment><comment><USER17> He says BinaryHeap is superfluous, but then complains there's not a priority queue. Huh?

A binary heap _is_ a priority queue. (Specifically, a binary heap is an implementation of a priority queue, just as a linked list is an implementation of a list.)

Even after the "they're fundamentally very different" update, he's still wrong.

Wanna know what the (non-synchronized) priority queue is called in Python? _heapq_ [https://docs.python.org/3.5/library/heapq.html](https://docs.python.org/3.5/library/heapq.html) Critique that next, please.

<comment><USER20> Yeah, he made an embarrassing mistake. I googled "rust binary heap" and the second link[0] is a priority queue example _using_ the std binary heap.

[0] [https://doc.rust-lang.org/std/collections/binary_heap/](https://doc.rust- lang.org/std/collections/binary_heap/)

<comment><USER17> The weird thing is...after having that brought to his attention, he reasserts his error.

</comment></comment></comment><comment><USER21> The variant of Robin Hood hash table isn't a double hashing scheme like the original research paper. This is more like linear probing with a collision resolution trick to reduce worst case in lookups.

The article suggests using quadratic probing instead, but that has two weaknesses. Cache locality is worse than linear probing. But the deal breaker is that the hash table must have a prime number size for correctness. This makes the hash table grow quite quickly once the size reaches tens of thousands. And finding primes is another issue.

</comment><comment><USER22> In all fairness I have yet to see a language with an awesome builtin collections library that meets everyones needs (and I use JDK collections all the time.... it took a long time to get where it is and still is sort of ok). If you know of a language that does please chime in.

The big thing I missed in my limited playing around with Rust is more types of queues. This is in large part because I was attacking Rust in a similar way to Java. Because of its lack of other concurrency models other than threads I was resorting to queues (I'm sure there are more "reactive-like" libraries now).

Overall I can't decide if a better approach might be to let library writers work on adding more structures instead of a batteries included approach. Maybe just have the traits included and thats it.

</comment><comment><USER23> > The other popular self-balancing trees are good candidates as well (AVL and > LLRB/Red-black). While they do essentially the same, they can have very > different performance characteristics, and switching can influence the > program's performance vastly.

In what scenario would you prefer an RB-tree (or AVL tree) to a B-tree?

My understanding is that the performance characteristics of RB/AVL trees can mostly be described as "worse." Maybe insert speed? But in that case, you'd really prefer an LSM tree.

The author is also very confused about how hash table DoS attacks are protected. And what a cryptographic hash is. There are very fast non- cryptographic hash functions like xxHash (in fact, I thought siphash was much faster than 1GB/s, but I could be misremembering).

<comment><USER24> GB/s is a fairly useless metric for hash-functions designed to be used in hash tables. This is because the keys for hash tables are usually very short, and keyed hashes can have long setup times. I don't know the speed of sip-hash for bulk data, but I wouldn't be surprised to see that VMAC is probably faster than siphash for large data, but VMAC has a long setup time (on the order of 5000 cycles IIRC compared to siphash24 at on the order of 100).

Heck, for large inputs, python's random hash isn't much faster than hmacmd5, but for 8 byte inputs python's random hash is faster than siphash24.

The better measurement is X hashes per second at N key size, and then perform that at a few key sizes.

[edit]

I finally found a comparison that does this and includes siphash:

[http://cglab.ca/~abeinges/blah/hash-rs/](http://cglab.ca/~abeinges/blah/hash- rs/)

Note that siphash is competitive with everything except FNV for small inputs, but FNV blows it away up to about 60 bytes.

<comment><USER25> These benchmarks are out of date -- Rust recently updated its SipHash impl from Sip2-4 to Sip1-3, making it actually the fastest for 8-64 bytes in some workloads (looking at the hashers outside of the context of using them in a map gives deceptive results).

(I need to get clearance to post updated results)

<comment><USER24> Good to know. The page I posted was nice in that it listed both (and included BTree for a comparison). I know nothing about how the benchmarks were run, but the fact that it shows varying sizes _and_ shows hashes both in isolation and in a map gave me confidence that someone who knows what they were doing was running the show.

I think not looking at both the bare hash performance and the map performance is a bad idea because there are a lot more variables involved testing against a Map, but poor distribution (which ought not be an issue with anything except FNV on that graph) could make a fast hash not useful.

</comment></comment></comment></comment><comment><USER26> I appreciate reading thoughtful, constructive criticisms like this. But ultimately, I didn't find any of his points paricularly compelling. Maybe the author can point to a language that really gets this right?

I haven't written much rust, though.

</comment><comment><USER27> I think std means standard collections, not custom ("special" case) collection library. People may look for this kind of specialization in outside std or create their own library. Or you could start be the first one who create this extended collection std.. CMIIW

</comment><comment><USER28> Typo: "alternatives and way(s) to improve it"</comment>


Docker Cloud Ends Cluster Management Services - <AUTHOR> https://docs.docker.com/docker-cloud/migration/ <comment><USER2> I'm disappointed that the timeframe is so short but I can't say that I am surprised. The writing has been on the wall for awhile now and I was already looking for alternatives.

The 'Standard' product was shut off abruptly and they tried to shove everyone onto their half-baked swarm mode platform. When users who were happy with the Standard platform (and confused by swarm) fought back, they re-enabled 'Standard' mode as opt-in. Unfortunately all development halted at that point and it has been more or less abandoned for over a year. They stopped providing updates on their managed nodes and stranded all of their users on outdated buggy versions with no way to update.

Also, there was quite literally 0 customer support for even for paying users unless you had contracts with them in the thousands per month.

Its unfortunate. As far as I was concerned, Docker Cloud (Standard, not Swarm) was very close to what I needed. As far as I can tell they got so caught up in battle for orchestration supremacy with Kubernetes that the left a good portion of their user base in the dust.

Perhaps this is a well calculated decision for them as a company, but from an end-users perspective, it feels like they lost their way and abandoned their users.

Anyone have suggestions for good hosted alternatives?

I'm looking for a service that offers:

1\. Hosted node management with nice simple UI

2\. A dashboard with visual health monitoring for nodes and containers

3\. Configurable alerts via email/slack/sms

4\. Github / auto-build / CI integration

I'm currently investigating [https://nanobox.io](https://nanobox.io) but am interested in any other suggestions.

EDIT: Formatting</comment>


Bop.fm (YC S13) Raised $2M for a Universal Music Streaming Service - <AUTHOR> http://www.businessinsider.com/universal-music-streaming-raised-2m-2014-7

<comment><USER2> Sounds like a promising start for them, and I hope it goes well -- especially now that they're taking steps to partner with the actual music providers.

However, like anything associated with the music industry, I'll take a wait and see approach to using it. I see no point in jumping on the latest thing if it's going to a) be sued out of existence, or b) sell out and get rolled into a company I don't like. Partnering with the other services seems like a good step towards avoiding bad-result a, so that's a promising sign.

The question left then is whether these folks are in it for the long haul, or if they're just in it for an "exit".

</comment><comment><USER3> The title of this article is a little confusing, as I thought it was referring to the Universal Music Group (UMG), one of the big four music labels.

A better term would be a streaming service aggregator, perhaps?

</comment><comment><USER4> It's crazy that something like this is even needed and everyone is perfectly ok with it. DRM is becoming the norm, and nobody is trying to stop it.

</comment><comment><USER5> tomahawk-player.org is an open-source solution for the same problem.</comment>


Stable Release of Orthanc, Free Server for Medical Imaging - <AUTHOR> http://www.orthanc-server.com/static.php?page=blog#stable <comment><USER2> I'm so hyped to see a good, free DICOM server with MWL that isn't dcm4chee.

While Orthanc came up in a toolchain review at my place of work (medical imagery R&D company), at the time it wasn't considered suitable because of it's in-development status.

Has anyone had a chance to use Orthanc so far, and if so, what sort of state is it in - what are its quirks and great bits? I'm particularly interested in how well it adds in PACS (they presently call it "Mini-PACS").

<comment><AUTHOR> Thanks for your interest. You might want to ask your question on the discussion group of the project to reach the community of Orthanc users ([https://groups.google.com/forum/#!forum/orthanc- users](https://groups.google.com/forum/#!forum/orthanc-users)). Also note that some Orthanc users who answered a survey are reported on the official Web site ([http://www.orthanc- server.com/static.php?page=references](http://www.orthanc- server.com/static.php?page=references)).</comment></comment>


Presentation Hacks and Tips (Naval Ravikant talk) - <AUTHOR> http://venturehacks.com/articles/presentation-hacks

<comment><USER2> This is by far the best summary of how to present to an investor I have ever seen. an absolute must read.</comment>


Microsoft Band out of fitness race this year, may not return - <AUTHOR> https://www.cnet.com/news/microsoft-band-fitness-wearable-out-of-race-this-year-may-not-return/ <comment><AUTHOR> I am not sure who won the fitness device race yet!! I think the technology needs to improve a lot when it comes to battery,accurate reporting and data syncing

I have used fitbit surge and chargehr.Both are not good with syncing over Bluetooth but battery life is gud because of monochrome screen.Reporting of steps is OK but I see it not counting basic steps at times.But surge looks really bad on your hand.

Moto360 - horrible battery life and in accurate reporting.

iWatch- my friends told me battery life is not great

Microsoft band-horrible battery life.

Most other fitness watches or devices I heard battery life is a problem or Bluetooth pairing and syncing has problems.May be that is a problem with Bluetooth itself :).

You cannot charge your watch or band everyday,at least not me.I have not come across a good fitness device which has good battery life and reasonably good smart watch capability and very stylish looks.Does anyone of you have good experience with fitness+smart watch device ?</comment>