tag:blogger.com,1999:blog-45137012151930895852012-02-20T22:53:27.411+01:00Hitchhiker's Guide to ComputersComputers, programming and random things I like or I like to rant aboutGionoreply@blogger.comBlogger121100tag:blogger.com,1999:blog-4513701215193089585.post-19531163395260467802009-02-15T15:00:00.008+01:002009-02-15T15:56:08.424+01:00Equal implies "less or equal", right? Right?!?Well, no, not really according to (my understanding of) C# language specification.
While reading the specification, I was struck by the definition of the relational lifted operators. The idea, roughly, is that if you've defined a relational operator working on, say, (non-nullable) types A and B, then the language automatically gives you a lifted operator working on the (nullable) types A? and B?.Gionoreply@blogger.com4tag:blogger.com,1999:blog-4513701215193089585.post-14763243342626051892008-11-02T13:27:00.003+01:002008-11-02T13:41:16.063+01:00Press play on tape - c64 revival bandIt's certainly not a secret I'm a Spectrum addicted, yet I have a thing for home computers in general. So, today I'll post something about a Commodore 64 (!) revival band. They're called Press play on tape and they really rock: my advice is to check their site out and enjoy their music.
Have fun!Gionoreply@blogger.com1tag:blogger.com,1999:blog-4513701215193089585.post-91198232619875825602008-10-26T22:40:00.003+01:002008-10-26T22:51:18.134+01:00Dog risks life for kittensThis is not a word play and the subject would be definitely off-topic if it weren't for the "random things" part of the blog subtitle ;)
Anyway, it's been a while since I posted something and I've found this piece of news quite moving.Gionoreply@blogger.com1tag:blogger.com,1999:blog-4513701215193089585.post-84509327813393521242008-09-16T15:30:00.002+02:002008-09-17T07:51:48.583+02:00Why java.io.PrintStream is badly designedSweeping the exceptions under the carpet is considered a bad practice, I mean really bad practice. Consider, for instance, try { do something} catch (SomeException e) { set a flag (or, even worse, do nothing!) } Obviously, one of the great advantages of having an exception mechanism is that programmers do not need to explicitly check for error conditions after every single statement: when Gionoreply@blogger.com0tag:blogger.com,1999:blog-4513701215193089585.post-69328534773052898952008-09-15T21:02:00.003+02:002008-09-15T21:09:15.059+02:00Who wants to be a researcher?In [Javascript is not enabled; please enable JS in your browser to see the counter]
function calc(secs, num1, num2) {
return ((Math.floor(secs/num1))%num2).toString();
}
function s(n) {
return n==1 ? "" : "s";
}
function runCounter() {
var dthen = new Date("8 Oct 2008 16:00");
var dnow = new Date();
var ddiff = new Date(dthen-dnow);
var secs = Math.floor(ddiff.valueOf()/1000);
if (Gionoreply@blogger.com7tag:blogger.com,1999:blog-4513701215193089585.post-63115009819335225102008-09-07T14:50:00.003+02:002008-09-07T15:11:18.140+02:00Running Turbo Pascal 1.0 on (a real) Spectrum +3As I wrote in my previous post, I was determined to run Turbo Pascal 1.0 on a (real) Spectrum +3. The issue is how to dump a DSK image file (on the PC) onto an actual three-inch Amstrad/Sinclair floppy disk (like the one shown in the second picture by a friend of mine who, by the way, is a very skilled hacker). One obvious way is to connect a three-inch floppy drive to a modern PC. While this Gionoreply@blogger.com2tag:blogger.com,1999:blog-4513701215193089585.post-50509360879896446142008-09-01T22:12:00.001+02:002008-09-01T22:15:47.948+02:00Running Turbo Pascal 1.0, on the CP/M, on the Spectrum +3 (emulated on Windows)I've never been a fan of the Pascal programming language; actually, I can't stand it... for a lot of reasons, many of which can be found in the (old and must-read) paper "Why Pascal is not my Favorite Programming Language" by Brian Kernighan. However, Turbo Pascal was different. The language was still not my favorite, but I have to admit it was far better than the standard one and the IDE was Gionoreply@blogger.com1tag:blogger.com,1999:blog-4513701215193089585.post-80787252111507318352008-08-12T17:16:00.006+02:002008-08-12T17:53:01.982+02:00A not so obvious answer to: Can Java interfaces have static initializers?Static initializers are blocks of code that are automatically executed when a class is initialized. They are particularly handy when an expression is not enough to calculate an initial value or when the evaluation of an initializing expression may throw a (checked) exception. For instance, suppose we want to initialize a (final static) field me with the IP address of the local machine. We'd like Gionoreply@blogger.com0tag:blogger.com,1999:blog-4513701215193089585.post-19417637522743477002008-08-08T12:09:00.001+02:002008-08-08T12:13:45.245+02:00Alice: a very cool way to teach programmingAlice is a freely available teaching tool designed to be a student's first exposure to object-oriented programming. The idea reminds me of the Turtle Graphics of LOGO, that is, making the programming activity more "tangible" by leveraging a parallel with the real world, where (real) objects can interact. Anyway, about thirty years have passed since those seminal ideas were born and Alice is Gionoreply@blogger.com1tag:blogger.com,1999:blog-4513701215193089585.post-2825104020752670072008-08-05T17:38:00.004+02:002008-08-05T18:32:39.884+02:00Installing fully encrypted Windows and Ubuntu on the EEE 900 In the last few days I've played a lot with my latest toy, an ASUS EEE 900, that I really love. The only thing I have a hard time with is its keyboard: it's very small, which is both cute and uncomfortable (anyway, an external rollable keyboard could easily solve this matter). I've managed to get Windows XP and Ubuntu working, sharing a data partition on a fully encrypted disk (well, actually "Gionoreply@blogger.com2tag:blogger.com,1999:blog-4513701215193089585.post-87668993840356952722008-08-04T16:03:00.002+02:002008-08-04T16:18:21.720+02:00Audiotapes, a trip down memory laneOnce upon a time there were homecomputers, that used analogue audio tapes to store programs. Those who've played with computers in the eighties will surely recognize some of these tapes from tapedeck.orgGionoreply@blogger.com1tag:blogger.com,1999:blog-4513701215193089585.post-9080275262654541972008-08-02T18:29:00.003+02:002008-08-02T18:33:01.399+02:00Achieving your childhood dreamsRandy Pausch was an American professor of computer science, who died from cancer when he was 47.
Randy has achieved worldwide fame for his "The Last Lecture", a speech entitled Achieving your childhood dreams, that manages to be touching, fun and extremely inspiring.
Gionoreply@blogger.com0