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copper

419 karma · joined February 14, 2008

http://www.hackernewsers.com/users/copper.html
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copper··on If PHP Were British
Strangely, I do that too. I tend to blame my education :)

Amusingly enough, (though not strange, if you consider its origins) Haskell uses the British spelling. Off the top of my head, the colour types are defined in the Data.Colour module.

copper··on The collected jwz bicycle wisdom
I dunno, doesn't $370 seem expensive too? I went through a few of these things[1] back in the day, and even now a new one should cost about the equivalent of $50. They're fixed gear, and likely not feature comparable, but they comfortable enough to drive uphill, light enough to actually carry around, and even on the kind of roads I used to drive, flat tyres were usually because of bent nails or broken glass.

[1] http://www.herocycles.com/jet2.htm

copper··on Stanford Fall 2011 - Machine Learning
I wonder if you could ask if the old problem sets for CS 229 could be made available without requiring a Stanford id?
copper··on C++ 11 Approved
This is why I rather enjoy discussing horrible hairy corner cases like this - there's always something I've overlooked :)
copper··on C++ 11 Approved
I'm interested in knowing what these are - barring an alignment-related weirdness, I can't think of any reason to do that.
copper··on C++ 11 Approved
Hm, I'd rather pay the cost of having to add a virtual keyword in a few places (easily found using the equivalent of g++ -Wnon-virtual-dtor, and you do ship C++ code that is warning-free, right? :) rather than have to deal with up to eight bytes extra per instance in all my classes.
copper··on Graphwar -- Artillery game where you use mathematical functions
The y' mode appears to have an unstable solver that's very useful :)
copper··on C++ 11 Approved
> Virtual functions are "costly" too, but C++ has them and it's considered poor form to not declare your destructor virtual.

It's a bit more subtle than that: a virtual destructor is only required when the class, or its base classes, already have another virtual function (and it's only really needed if another class inherits from it. hmm.) At that point, a virtual destructor doesn't add any more cost over and above the virtual function that's already defined.

copper··on C++ 11 Approved
> C++ has too much stuff going on behind the scenes. (Like hidden object copies, potentially bloated operators, etc.).

The thing is, C++ is usually good about not charging you for features you don't use - and with the reasonably good debugging and profiling tools, most of the problems you mention above are fixable to get performance that is close (or equal) to C, with maybe better maintainability.

To pick a not-so-random example of something that's difficult to implement in C as safely as in C++, see expression templates[1]. I'd be interested in something similar to what eigen does written in C. (Of course, the last time I did this minibenchmark, so-and-so's lapack library was still slightly faster than eigen :)

The bottom-line, perhaps, is that if I'm writing a library, I'd do it in C simply because it's self-contained and has a nicely limited scope, and as a bonus is usable from oh-so-many other languages. If I'm writing an application that really, really requires serious performance, I'd prefer to use C++.

[1] http://en.wikipedia.org/wiki/Expression_templates

copper··on Can we believe our eyes? Misleading people with Unicode.

     attrib +h
at the cmd prompt, the file properties in explorer would have a checkbox for this too
copper··on Algorithmic trading -- the positive side
Thanks, thats interesting. It seems unfair to use the HFT to create stability, and then penalize it for that. I suppose that can't be fixed easily, though.
copper··on Algorithmic trading -- the positive side
> I.e., if an HFT pushes accenture up from $0.05 to $1.00 and sells at $35, following which accenture eventually goes up to $40, they run the risk of having their $1.00 buy trade broken. Then they are stuck with a short sale at $35, while the price of accenture went up to $40.

Shouldn't both trades be broken, though? Breaking just one sounds like the kind of behaviour that would be a strong disincentive to trade at all in the first place.

copper··on C No Evil
> free(*ptr++)

Yes, of course - that's what I thought I'd written. Clearly not :)

copper··on C No Evil
Function calls seem right - particularly if they're badly written. Also, this macro might give curious results when passed in ptr++ .

While this is C++, I've actually seen this particular construct: delete new SomeClass(...);

used as, basically, an eye-poppingly clever way of initializing something, doing work, and then cleaning up after.

copper··on It's possible to determine your pulse based on how you click.
Very nice - isn't the HN title a bit misleading, though? I was under the impression that it would find my pulse rate :)
copper··on Designing command-line interfaces
If you don't have an easy way of installing boost, it becomes complicated - just to compile one program.

That said, boost is a dependency that pays off in terms of programmer time if what you're doing is complicated enough (in other words, if you think you might reimplement some part of boost, you're better off using it as a dependency instead.)

copper··on What's Special About Lisp?
Or Shriram Krishnamurthi's Automata via Macros - a beautiful little nontrivial example of Scheme macros:

http://www.cs.brown.edu/~sk/Publications/Papers/Published/sk...

copper··on The Most Expensive One-byte Mistake
Hm, It can be a real problem if you have the joy of working with old C++ code: the initial codebase might have had its own string type, and then some more classes added by long-gone programmers who thought the earlier types were slow, and then newer code added by people who actually use std::string (well, you get the idea).

(much to my regret, that is a true story.)

copper··on Ask HN: Who is Hiring? (August 2011)
Yes, I'd hope so too :) There should be quite a few people who've successfully engineered microbes and plants (by extension, fungi), but for the others, I was wondering just how many candidates there could be.
copper··on Ask HN: Who is Hiring? (August 2011)
OT (and I'm sorry), but I couldn't resist when I saw this requirement:

> Candidates should hold a PhD or equivalent and have successfully engineered an organism -- plants, fish, microbes, worms, fungi, it doesn't matter, as long as it worked.

Are there that many people who've actually done this? It makes me wish I could apply for this job :)

copper··on I am an HFT Programmer
Google's T V Raman is a personal hero. http://www.nytimes.com/2009/01/04/business/04blind.html
copper··on Ask HN: Would a startup sponsor my visa?
So, something like taking some time off before you start at the new job would be frowned upon?
copper··on Ask HN: Would a startup sponsor my visa?
As I understand it (I'm looking for a job in the US too), if you switch jobs, the new company more or less needs to redo all the paperwork that the old one has done; and yes, being self-employed is not an option.

I also believe - but am not sure - that once you have a visa that lets you work in the US, any current tourist visa you have is cancelled, making staying there when you're between jobs is a major undertaking (at least in my case, I think it means a trip back home and to the consulates here to get the visa changed, so that may not matter all that much.)

copper··on How to work with me - a no BS approach
If I can offer my own reaction as a guide, I'd find the list less rude if I could trust it was written by someone with an actual record of successful management. I've known a few people who talk this way, and had a past record of turning projects into Hell Marches.

That said, I'd be interested in what you think of raldi's take on this list - he's rewritten it to be both concise and, (lacking a better word) classy. It is far less likely to raise hackles and makes an interesting comparison to the original. And well, knowing his record, I'd much rather work with Mike than with whoever wrote the original :)

copper··on How to work with me - a no BS approach
I might agree about the better person being basically irrelevant, but I've seen a lot of projects run into the ground by assholes - I guess my basic point is that being an asshole is only weakly positively correlated with being a competent manager.
copper··on Show HN: We want to become India's TurboTax. Feedback?
Indeed. In my defense, anecdotal evidence: quite a few people in what we call the super-senior citizen bracket (yes, really) do pay taxes, and more than a few of them don't speak English.
copper··on All that is wrong with the Recruitment Industry
I've met more than a few recruiters who do that here too.

In fact, I think I have even worse stories to share: one recruiter who shall forever remain in my email blocklist took my resume, promised she'd ask me before sending it to any company, and then, naturally, sent it to a place where I was already having discussions, which led to quite a bit of unpleasantness all around.

copper··on Poll: Do you use Google Reader on a daily basis?
The API does offer an import OPML option, so I assume the website does too. Unfortunately, I've gone and forgotten my newsblur login/password combo, and so can't verify that for you.
copper··on Show HN: We want to become India's TurboTax. Feedback?
The rules are similar, and a bit more generous if you're female, or above a certain age. As for the other part of that statement, you'd be surprised at how many people in that bracket can speak English - at least well enough to use a cell phone :)
copper··on Show HN: We want to become India's TurboTax. Feedback?
I /hope/ Ayush's PAN info in the video is fake :)

In my opinion, your prices are too low on the higher end. A normal tax return preparer charges something like Rs 250 (negotiable, particularly on bulk deals) to around Rs 500 for a simple ITR-1/ITR-2 return. For people who require audited returns, It would be an order of magnitude more. I take it you don't do those :)

Either way, best of luck!

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