Is it better to remain blissfully unaware…

Posted on May 31, 2010 by aaron

I was once asked “why bother learning these other languages, if you can’t use them”. It hadn’t occurred to this person that I code off hours. I’ve also been asked “what if you find these other languages actually are better than C++? Won’t you find it depressing having to code in a normal language then?”

It’s a good question. I don’t know if there’s one answer, but I’ve found mine.

Learning Lisp, Haskell, Python, and others has given me a greater appreciation for computer science, for the theory and universe of knowledge that lies underneath the surface of programming. Now when I code, I don’t just solve the problem at hand. I see different ways to solve it. I see other remote problems its related to. I appreciate the aesthetic of it all.

It’s not for everyone, but I find the mathematics underlying it all very beautiful.

And as for my day job in old-school-C++? Well, I hack together a prototype in Python in a couple hours, then spend a week translating it to C++ (adding verbosity, manual error handling, unfolding metaprogramming, etc). My boss doesn’t necessarily understand the whole languages thing, but he’s happy when I get a 2 wk job done in one. I’m happy too; having gotten through the icky bits of the problem in Python, I spend less time working on the boring bits in C++, and can move on to the next project sooner.

There is one last question, that I’m not sure I really have a good answer to. “Won’t you be tempted to use features that don’t exist in a normal language?” I’m hoping this will evaporate. Templates have existed in C++ since ’88 (pdf), various people have hacked lambdas in, and VC10 has added them for real. Short those facilities, it’s not like I have forgotten how to write imperative code. It’s still an option – I just now realize the development expenses of that option.

~

I’m curious, other answers do you choose for these question?

Posted in languages | 2 Comments

Best way to learn a Programming Language

Posted on May 27, 2010 by aaron

(Update, added Casting SPELs)

For better or worse, it’s accepted in our industry to be fluent in only a single programming language or technology. It’s lame, but there are plenty of excuses for this. “Turing equivalence” right? Finding quality tools is hard. And worse yet, to learn a new language you have to spend days and weeks reading some lame introductory text, right? Wrong!

There are tons of good intro guides out there that can get you up and running quickly, if only you know where to look. I’ve accumulated a bunch of these, and would like to spread the good wealth:

Learn You a Haskell, example image

Continue reading →

Posted in languages | 2 Comments

Comma Abuse

Posted on May 5, 2010 by aaron

Found this old C++ source file in my scratch directory, apparently from last September. I don’t even remember writing this, but it’s written using my idioms. If I did write it, rest assured it was primarily for amusement purposes (abusement purposes?) only.

#include <iostream>
using namespace std;

int fibonacci(int x) {
    int a=0, b=1, temp;
    while(x?(--x,temp=a,a=b,b=temp+b):0);
    return a;
}

int main() {
    int i = 0;
    while(i<10&&(cout<<"fib("<<i<<")="<<fibonacci(i)<<'\n',++i));
}

Yeah. That was terrible. Terrible awesome. But looking back, I’m realizing that some of the comma abuse is superfluous:

int fibonacci(int x){
    int a=0, b=1;
    while(x?(--x,a=((b=a+b)-a)):0);
    return a;
}

Don’t let anyone check in code like this, ever.

Posted in C++ | Leave a comment

Typography for Lawyers

Posted on April 22, 2010 by aaron

… And for everyone else. Typography for Lawyers; an easy read, very accurate, and despite the title, the typography advice is really for everybody.

Well, maybe not for typographers. I get the impression this is all entry level stuff.

Continue reading →

Posted in non-tech | Leave a comment

Cache effects

Posted on April 19, 2010 by aaron

Quick call out to an illustrative blog entry on various cache effects.

http://igoro.com/archive/gallery-of-processor-cache-effects/

When someone bugs me about “X is too slow, because it has to make a virtual call”, and I get annoyed, it’s because a hot virtual call is an overhead of some dozen cycles or so.  Missing the cache?  In the thousands.  Don’t get me wrong, virtual calls can matter for many reasons, but that all flies out the window the moment you’re working on any non-trivial sized data set.  If your objects are 100′s of bytes large, you don’t worry about the virtual calls, you worry about shuffling their member slots around to squeeze more out of your caches.

“It better not allocate”

My other favorite perf quote from this month: “It better not allocate — this call needs to take 100 microseconds or less”.  On my dev box, on the default Win7 heap, an uncontended small allocation (and the pairing free) is 120 ns — or 0.12 microseconds.  My personal favorite small object allocator can hit down to 0.020 microseconds sustained.

We could allocate thousands of objects per call and still come in under budget.

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[ot] 500 mile email bug

Posted on February 19, 2010 by aaron

Just a humorous software bug story, the case of the 500 mile email:

"We're having a problem sending email out of the department."

"What's the problem?" I asked.

"We can't send mail more than 500 miles," the chairman explained.

I choked on my latte.  "Come again?"

A must read for CS/IT folks.

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My programming languages story

Posted on February 13, 2010 by aaron

It’s bad style, but I must start with an aside:  on reddit/scheme, there was a link to a blog series on developing a Scheme interpreter over January 2010.  It might not implement any particular Scheme standard or particularly many libraries, but it’s got all the functional elements.  Bootstrapping a programming language is fun and easy.

Anyway, he also posted a his personal history of programming language study, and it got me thinking about my own personal programming languages history.

It all started with Logo…

Continue reading →

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Busy with v2

Posted on January 26, 2010 by aaron

Been busy with my personal version 2, Evelyn or Evie for short, who is now 2 and a half weeks old.

Say hi Evie ^_^

Posted in baby, non-tech | Leave a comment

Comparing "Go" to "Brand X"

Posted on December 25, 2009 by aaron

The old-timers might figure out what Brand X really is before the end. For the rest of us, the reveal at the end is just as shocking as the author intended.  All and all, it confirms what I suspected: Go nice enough, but it is hardly original.  Sure it looks like a great language to write in compared to C, but then again, what doesn’t?

Comparison of Google’s new language “Go” to mysterious “Brand X”, and the shocking reveal of Brand X’s true identity.

As found through http://www.foldl.org/, a digest blog on various programming language topics.

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Native Client at UWCS lecture

Posted on November 26, 2009 by aaron

Available for streaming and download, Google Native Client presented at UW’s computer science lecture series. Covers the restrictions on x86 code, new alignment rules, and performance on various benchmarks. 5% overhead, that’s nothing compared to many other sandboxing techniques.

Native client is 50KB download?  Wild. It really is just a gatekeeper, runtime library separate.

Of course, I would love to get away from x86.  LLVM, or ARM, or even Amd64.  x86 makes me a sad panda.

Posted in C++, tech talk | Leave a comment