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mrkgnaoon The Blockstack Browser: A Gateway to a New, Decentralized Internet

It's not a particularly good sign that the gateway to this "gateway", as it were, doesn't like you not having JS enabled.

mrkgnaoon Show HN: 15-question programming quiz with answers

I like the idea, but my first reaction was that this is a test of how well you know Python's quirks (like the problems with not deep-copying things).

But then I realised that that's not true. For example, call-by-value and call-by-reference are pretty pervasive across languages: many of those examples would've worked the same in Java, say. It's not familiarity with Python, but rather familiarity with a certain kind of language (which admittedly constitutes the majority of those used in industry ATM) that the test demands, at a time when even Java is getting nice FP-like abstractions and the JavaScript community is cooking up all sorts of ways to bring the benefits of that kind of thinking to their own work (from React/Redux all the way to Ramda and the like).

If you're more used to languages that "get out of the way" by eliding what could very well be termed "implementation details" (e.g. is there any reason[0] to use call-by-reference in the absence of global mutable state given a "sufficiently smart optimizing compiler"?), I'd predict (n = 1) that you'll be more likely to make mistakes.

I would've done far better on this quiz back when I was playing with matplotlib as an eighth- or ninth-grader: apart from the token map implementation, the quiz really favors knowledge of counterintuitive behavior common in "mainstream" imperative languages over an understanding of "composability" that users of modern functional languages are used to. (And no, that doesn't only mean Haskell or "ultra-Haskells" like Idris, but also languages like OCaml, F#, and so on.)

It would be much nicer if the quiz could be less about the candidate coaxing her preferred meaning out of a language implementation and more about testing the meanings a candidate knows how to implement with the help of the language.

[0]: For instance, the standard reaction to things like

    sum (map (\x -> x ** 2) (map (\y -> sin (y * pi / 10)) [0..9]))

is that a single for-loop is better than this for "real-world purposes". That is very false: the Haskell vector package is usually capable of efficiently fusing the code above into exactly what one would've written by hand.

https://www.schoolofhaskell.com/user/commercial/content/vect...

At the risk of going all peak-HN, these things are more a problem with implicit, nonuniform behavior which well-designed languages solve with abstractions like the Copy trait in Rust or even C++ move semantics.

mrkgnaoon The Quants Run Wall Street Now

I think it's not like there are tons of qualified people with a great interest in quant-y things whose only barrier to entry is a lack of data. It's sort of a monopoly+monopsony thing (I guess, this is highly likely wrong) where there's no incentive to expanding sales further because you're already hitting almost the entire market, and entry to the market isn't a problem for potential buyers.

mrkgnaoon Topics in Core Mathematics at Graterford Prison

> Christopher is an inmate in a high-security federal prison not far from Atlanta. He’s been in trouble with the law since he was 14. He didn’t finish high school, had an addiction to hard drugs, and at age 21, his involvement in a string of armed robberies landed him in prison with a 32-year sentence.

> Right now, you’ve probably formed a mental image of who Christopher is, and you might be wondering why I’m opening my speech with his story. When you think about who does mathematics–both who is capable of doing mathematics and who wants to do mathematics–would you think of Christopher?

Francis Su's retiring address as the President of the Mathematical Association of America is one of the most powerful things I've ever seen.

https://www.youtube.com/watch?v=xEtDvc1SWm8

There's a transcript on his blog, too:

https://mathyawp.wordpress.com/2017/01/08/mathematics-for-hu...

mrkgnaoon The Quants Run Wall Street Now

Without a minute understanding of what's involved, I'd guess that normalizing is a non-local operation, in the sense that the effect of normalizing some x depends on the other elements of your dataset, so that normalization includes the "information" of the rest of the data implicitly.

In real life, that's sort of like having access to the answers when you're given the questions. Being trained in that environment won't do much good.

mrkgnaoon We Aren’t Built to Live in the Moment

The comments on this remind me of the somewhat-related koan (from the Jargon File?) about how an apprentice tried to randomize the weights on a neural network to "rid it of preconceptions", and the master responded by closing his eyes "so that the room would be empty".

mrkgnaoon We Aren’t Built to Live in the Moment

For others who don't know: taijiquan is more usually called tai chi.

mrkgnaoon Nasa revives 'weird life forms' trapped inside crystals for 60,000 years

Yes, it's a linguistic dangling else.

(I think so, at least. Not too sure.)

mrkgnaoon So You Want to Write Your Own Language (2014)

Does Racket support non-Lisp-like syntax for DSLs written in it? I've been hearing really great things about how it has the best macro system on earth, but Haskell has spoiled me to the extent that I'm a bit lazy (no pun intended at all) to look at things outside of that broad area (so Idris, PureScript, etc.) nowadays, but Racket seems to be interesting enough that (to continue the pun) I can afford a bit of IO for it.

Most of my interest stems from this excellent project in Racket that's shaping up to be quite something:

https://github.com/lexi-lambda/hackett

It uses the "type systems as macros" paper's approach to create a Haskell-like language in Racket.

(btw, I think you meant e.g., not i.e.)

mrkgnaoon Volta: Advanced Data Center GPU

"Thinker's Universal Workers"?

mrkgnaoon The Pain of Real Linear Types in Rust

GHC already does a lot of loop fusion and optimizing away of linked lists (which is good given the unfortunate overdue of cons-lists over nicer things among Haskell users) which can be extended to work with user code using rewrite rules. Libraries like text, bytestring, and vector do exactly the elision of intermediate structures that you talk about, allowing you to convert from a vector to a list, apply some function that annoyingly only works with lists, and convert back into a vector, and have that compile into a single tight for-loop in many cases.

I wonder what the upcoming linear types work will do.

mrkgnaoon Jeff Varasano's Famous New York Pizza Recipe (2008)

My first exposure to this was Kramer on Seinfeld talking about how people want to make their own "pizza pies".

mrkgnaoon Ask HN: What's your working day like?

"Non-strict, not lazy"

mrkgnaoon Why Are There So Many 17th Century Paintings of Monkeys Getting Drunk?

For one, I often read Dan Piponi[0] / sigfpe's articles on my phone, and they sometimes have long equations that stretch off the page. If you drag the page in the commonsense way, you end up moving to another post, as you say: I've somehow subconsciously learned to drag at an angle and then correct by scrolling up or down as needed. It's sad that it has to be done, but it works.

[0]: Here's a delightful classic with pictures: http://blog.sigfpe.com/2009/05/three-projections-of-doctor-f...

mrkgnaoon Chasing diagrams in cryptography (2016)

The first line of the abstract reminds me of some recent work allowing plain Haskell functions to be sent to the Z3 theorem prover/SMT program:

http://newartisans.com/2017/04/haskell-and-z3/

It leverages some cool work of Conal Elliott that develops (formulas in) cartesian closed categories into something like an "intermediate representation" for functional language compilation.

http://conal.net/blog/posts/haskell-to-hardware-via-cccs http://conal.net/blog/posts/overloading-lambda

http://conal.net/papers/compiling-to-categories/ (the "LaTeX goals" ICFP 2017 paper)

Also, something I always like to link when this kind of thing comes up: the salamander lemma!

https://sbseminar.wordpress.com/2007/11/13/anton-geraschenko...

https://mathoverflow.net/questions/6749/a-proof-of-the-salam...

mrkgnaoon Why Germany Educates International Students for Free

I'm a graduating senior in India, interested in studying math as an undergraduate.

Considering that I know some German (~B1), could this work out for me?

mrkgnaoon Why Religion Is More Durable Than We Thought in Modern Society

cf. the "non-golfing club" joke I can't remember who made

mrkgnaoon Why Religion Is More Durable Than We Thought in Modern Society

> reading religious texts and religious philosophy

as texts and philosophy, yes, as works of fiction-unless-evidenced-otherwise, as literature that chronicles a staggering amount of human history, large-scale social organization, belief and gullibility and "leaps of faith", the search for meaning, and so on.

They are very useful as books.

mrkgnaoon What makes a genius?

The conviction that the world, pace certain "intrinsic" limits of the information-theoretic or quantum-mechanical nature, is understandable is a singularly powerful one. It's something lots of people think they believe, but it took me (anecdotally) until I was 9 or 10 to internalise it. The belief that the X-ray vision you speak of exists is enough in many cases for one to "get" it.

I do not mean to start a tangential flamewar, but the ability to accept and be comfortable with not knowing, while at the same time believing that the unknown is not unknowable, is something a certain kind of religious worldview precludes. This is one thing which I realised quite early on that my parents didn't share my beliefs on: for them, there's some underlying agent that chooses what happens in situations that we call random or do not understand:

"I don't know why this happens, but there's no reason why we never should/it's not computable/etc."

"Ah, child, it's time to accept things as they are. When I do not understand, I say God's causing it to happen."

It's a confusing mixture of the different positions one can take on determinism coupled with a sort of complacence I find remarkable.

mrkgnaoon Hacking the Hivemind: Predicting Comment Karma on Internet Forums (2014) [pdf]

Compare this low-effort comment:

https://news.ycombinator.com/item?id=14124411

to these:

https://news.ycombinator.com/item?id=14149200

https://news.ycombinator.com/item?id=14016438

Getting "in" when a post has few comments and is going to attract a lot of comment readership quickly or stay on the frontpage for a while is probably more important than pure comment quality.

mrkgnaoon Why I published in a predatory journal

In addition to the more well-known

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

although that had different goals.

mrkgnaoon From Monads to Machine Code

That's true, for bitflag-like things OR does make sense.

mrkgnaoon From Monads to Machine Code

There is no canonical monoidal operation on booleans (just as the case is in any arbitrary ring), so I'd guess using the bitwise operators explicitly is good for disambiguation.

mrkgnaoon From Monads to Machine Code

(With a short detour through writing a JIT in LLVM, of course, but I didn't want to edit the title. Sadly, I accidentally added the "from" at the beginning.)

mrkgnaoon Spheres

Thanks for correcting my mistake.

It seems like there's a way of taking some part of speech, adding a suffix to turn it into a different one, and then adding another suffix to turn it back into the original kind, then declaring that the meaning of the word thus constructed is now whatever one chooses it to mean. So the meaning of the original word is subconsciously palpable, but you make yourself see the new word differently and there's a bit of tension.

mrkgnaoon Computer scientist Viral Shah helped build Julia from Bengaluru, India

Manish Goregaokar[0] is a well-known Rust developer, and afaik he studied at IIT Bombay before going on to Mozilla. (Apologies if this is incorrect.)

[0]: https://github.com/Manishearth

mrkgnaoon Spheres

> Offenbarkeit

Does that translate to something like "openability"? (I've had the occasional brush with Heideggerian terminology before.)

mrkgnaoon Alexander Grothendieck, a genius of mathematics (2015)

And a suitable inversion tells you that both are almost the same :)

mrkgnaoon Tesla's Musk Paid at Least $593M in Income Taxes in 2016

https://en.wikipedia.org/wiki/Marginal_utility#Diminishing_m...

Interesting.

mrkgnaoon A Mind is Born

This has a beginning that you may find interesting.

https://en.wikipedia.org/wiki/Diaspora_(novel)