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User: david.given

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  1. Re:Verilog on What Programming Languages Should You Learn Next? · · Score: 3, Informative

    JavaScript/EcmaScript -- has nothing to do with Java. Dynamic everything, closures, first-class functions -- most of the Lisp-y goodness, but you already know the C-like syntax.

    *shudder* Arrgh.

    Javascript is not a nice language. It has all the features you say... but most of them are broken.

    Dynamic everything? Yup, it's got that. Except that its primary data structure, the Object (an associative array, basically) coerces all keys into strings. This means that if you try to use another object as a key, it gets coerced into something like "[Object:0x12345678]", and that string is actually what's used... with hilarious results if you actually want to use the keys as anything other than simple hashes. Yes, this happens with numeric keys in arrays, too. And since all the data storage classes share method and data namespaces, which means you can't combine named and numbered items in an array without running the risk of overwriting the array methods.

    First-class functions and methods? Yup, it's got that... with some *really weird* semantics when it comes to 'this'. Basically, if I have a function foo(), I can call it in three ways: foo(), object.foo(), or new foo(). Each way, the function gets called. 'this' gets assigned differently in each one. In the first, the current value of 'this' gets propagated into foo(). In the second, foo()'s 'this' gets set to 'object'. Yes, this means that these two lines behave differently:

    object.foo();
    var f = object.foo; f();

    (The new foo() case is still pretty strange, but at least it's consistent with what you'd expect.)

    C-like syntax? Yup, it's got that... but C-like syntax is entirely unsuited for a dynamic language like this, because a C-like syntax implies C-like semantics. Like var. var defines a local variable, right? No, it doesn't, it assigns a new value to the current object context. Which means the value remains valid after it looks like it's gone out of scope. Don't believe me? Open up Firefox's error console (in 'Tools') and try any of these lines:

    var a=1; alert(a);
    { var a=2; } alert(a);
    var a=3; { var a=4; } alert(a);

    (The answers are 1, 2 and 4.) If you're used to C, C++, Java, C#, D, or any of the other horde of Algol-based languages, Javascript *lies* to you.

    The fact that Javascript has closures is its one redeeming feature, IMO.

    The thing about optional semicolons is pretty horrible, too. Try writing a parser for it some time.

    If you're interested in dynamic languages, of which Javascript is one, I'd strongly suggest checking out Lua; it's way faster than Javascript, it has all of its features implemented in rather more consistent ways, and is so tiny that one person can understand the entire language (library included) with ease. I do most of my programming in it these days.

    (I agree with all your other language choices, BTW; although I'd add Forth to the list as an example of a radically different low-level procedural language, and I'd emphasise Smalltalk more. Smalltalk is a beautiful language. All the shiny new language features people are rediscovering today, Smalltalk had in 1980. Concurrency, dynamicism, polymorphism, extreme programming, closures... it had 'em all. And nobody noticed. It's a shame...)

    Sometimes, these things are mutually exclusive -- how do you have a purely-functional, lazily-evaluated language, and also make it simple and imperative?

    You might want to check out Io.

  2. Re:So... on NASA to Test Emergency Ability of New Spacecraft · · Score: 1

    Feel free to insert the following paragraph breaks whereever in the previous post you so wish:







    Stupid frickin' comment submission system...

  3. Re:So... on NASA to Test Emergency Ability of New Spacecraft · · Score: 1

    If it's the same as the old Saturn system, it's not an 'ejection system' in any traditional sense of the word. Rather, it's a set of emergency rockets attached to the crew capsule that, in the event of emergency, can lift the capsule up and away from a fireball sufficiently quickly that the crew will survive. The capsule then descends safely on its own reentry parachutes. Remember that the capsule is designed to withstand reentry, and that exploding rockets aren't actually very violent --- they look impressive but there's not much actual explosive power. The main point of the escape system is to ensure that the capsule is far enough away from the fireball, and far enough up, that parachute descent is safe. Was the Saturn escape tower ever actually tested? I know it was never used in anger...

  4. Re:what's next? on Courts Force Danish ISP to Block Torrent Tracker · · Score: 1, Interesting

    No, but I believe the GP is getting at the fact that Google can be USED like a tracker...

    How? Does Google's cache software support the Bittorrent tracker protocol? If so, how do I use a .torrent that's been configured to use a different tracker server to use Google's instead?

  5. Re:Basic physics: no. on Body Heat Could Charge Your Cellphone · · Score: 2, Interesting

    SO, the most energy we could possibly get out of this generation system is 0.6 * 1.7% = 10 milliwatts... This idea's dead in the water at the basic physics stage, before we even get to the engineering considerations.

    Actually, 10mW is loads. You're not going to charge batteries off that or run a GSM phone, but it's more than ample for powering things like wristwatches, calculators or medical sensors; and with appropriate design, there's no reason why you couldn't build a PDA that worked at that kind of power level. Microchip make a 16-bit PIC that runs at about 1.3mW per MIP. Combine this with an eink screen which only uses power when updating, burst radio powered by a capacitor for low bandwidth data transfer, and a lot of static RAM (which has standby loads in the microwatt range), and you could easily come up with a basic but useful device.

  6. Re:The best tools stay out of the way... on Goodbye Cruel Word · · Score: 1

    Lame.

    Of course, if you'd actually gone and looked at it, you'd realise that there's a very good reason why WordGrinder needs its own save format...

    Any plans for supporting OpenDocument?

    Maybe. The problem is, OpenDocument is a pig to write, and especially a pig to write quickly; because it all lives in a zip file you have to do a two-stage save procedure where you write out a bunch of files and then zip them up. Since, in addition to this, the OpenDocument document model matches WordGrinder's own document model really badly, the chance of WordGrinder adopting it as a native file format is nil. However, it'd be perfectly possible to export OpenDocument via the modular import/export interface; all it requires is someone who knows the OpenDocument schema, unlike me. Would you like to volunteer?

  7. Re:The best tools stay out of the way... on Goodbye Cruel Word · · Score: 1

    In all honesty, I'd love a program crossing interface with Nano/Pico and Wordperfect.

    I feel exactly the same way. I wanted to do some writing and couldn't find a word processor I liked. So, er, in possibly the world's most extreme cat-vacuuming exercise, I wrote one.

    WordGrinder is a character cell word processor than runs in a terminal. It's Unicode-aware and uses Unicode extensively in its UI, so you'll need a terminal that supports it. It is specifically designed not to support much markup; it's a word processor, not a DTP package, so all you get is italic and underline and a small set of predefined paragraph styles. It's very small and very lightweight and contains just enough functionality to be useful. It imports and exports HTML and text, but has its own save file format.

    In fact, I'm currently using v0.2, which contains some more useful features (word counts...) and a lot of bug fixes, but that's not out yet; I had to reinstall my machine and for some reason gnome-terminal is refusing to display unicode, grr. But v0.1 ought to be quite usable as-is and v0.2 should be out soon. Just remember to save regularly and always back up your work.

    If you give it a try, let me know what you think...

  8. Re:and in its place... on Burying a Mainframe In Style · · Score: 2, Interesting

    Mainframes tend to be at least triply-redundant in virtually every single component. Any event that would bring down a "good" mainframe (eg. server room hit by asteroid) would almost certainly bring down all 25 replacement servers as well.
    There's an old story, possibly apocryphal, about a mainframe (a Vax, IIRC) in an upper-floor data center. There was an earthquake, and the building was heavily damaged. When they went in afterwards, they discovered that the mainframe was still running and still responding to remote queries... despite the floor having given way underneath. The thing was running off its emergency power while dangling from all of its cables. Their customers hadn't even noticed.
  9. Re:Guitarcraft: Lords of Music on Blizzard and Activision Announce $18.8bn Merger · · Score: 4, Interesting

    How long until I can play some crazy rhythm-based RTS with my guitar hero controller?

    You know, that might actually be quite fun. Did you ever play Loom? That was a point-and-click adventure game where all your actions were done by playing short phrases of music.

    Update it to the present day, and you have your character roaming the wilderness blowing monsters away with your sw33t r1ffs. The more powerful the spell, the harder it is to play, so your character's skills are directly related to your skills. If you could solve the lag issue, you could even have the ability to team up with other players and jam together for extra power.

    Hmm. Different character classes would map to different types of music quite well. Healer == psychedelic 60s. Tank == 80s power ballad. Fighter == rock. Necromancer == death metal...

  10. Re:Problems never end on Minor Leak Being Investigated Aboard the ISS · · Score: 5, Interesting

    That said I have to wonder if the ISS could be bumped into a lower maintenance orbit and used as a hub for a bolo style rotating space station.

    It's too low as it is --- there's enough air resistance that it has to be reboosted at intervals to keep it in orbit. (It has to be that low because otherwise the shuttles can't get there. They have lousy range.) Lowering the orbit any further would be very dangerous.

    As for spinning it (you did mean bola, right? Unless you were actually thinking of giant robotic tanks, which I will admit would be quite cool), not only is it not designed for that and would fall apart, but if you want gravity there's plenty on Earth, where it's quite cheap. One of the main purposes for getting into space is to get free fall.

    I rather regret that Mir was destroyed for purely political reasons. If the ISS was built as a set of add-on modules to Mir, gradually superseding Mir's own modules as they began to break down, construction could have gone a lot faster. Even if the Mir modules stopped working completely, they'd still have considerable value as salvage.

    Rather than a trip to the moon, I would be far more excited to hear about an ISS greenhouse that does all of the air and water maintenance.

    I want a balloon. A ten or twenty metre inflatable habitat module, semitransparent hopefully, in which plants a grown. Inflatables and plastics are the future of spaceflight; look at the cool stuff that Bigelow Aerospace are doing. But even they are simply replicating existing modules using inflatables. It ought to be possible to use the new materials to radically change the way space stations are built. How about a 100m wide spherical envelope, full of air, with your space station built inside? Now, that would be cool, particularly once you have a decent amount of plant life in there...

  11. Re:first? on New Results From Venus Express · · Score: 1

    I'm always amazed when i read about the Venera program. The soviets did some incredible advances in the aerospace field back then.

    The Soviet space achievement that I'm amazed nobody's ever heard of is the Lunokhod programme. Two robotic rovers, landing on the moon, around 1970. They were remote-controlled from earth, driven manually via a TV link. Lunokhod 1 lasted for just under a year and travelled about 10km, Lunokhod 2 for four months but managed 35km.

    After they died, they were sold off to private individuals. Apparently, one of them is now owned by Richard Garriot.

    Between them they transmitted over 100000 TV pictures back from the moon about about 100 panoramas. You can find some of them here (along with other Soviet-era moon exploration imagery).

  12. Re:Some but not much on Voyager 2 Set to Reach Termination Shock · · Score: 1

    as for Voyager 2..... well the data USED to be in wikipedia, but its missing right now, what it does say is that its going slower than Voyager 1 which is traveling at 38,400mph. making it 8,000mph slower that New Horizons.....

    Yeah, but Voyager 1 is a hell of a lot further out of the Sun's gravity well than New Horizons. NH has to climb out of the well, and is going to slow down, which means that NH will never catch Voyager. I gather the relevant phrase is 'hyperbolic excess velocity'...

  13. Re:Some but not much on Voyager 2 Set to Reach Termination Shock · · Score: 1

    It would be interesting to see a new voyager sent out. In particular, obtain bigger nukes, use bigger rockets (perhaps the ares IV/V), and finally, add ION drives.

    Do you mean like New Horizons, which recently passed Jupiter (and took some stunning pictures, too). It's due to fly by Pluto and Charon in 2015, and enter the Kuiper belt shortly after.

    Okay, it's not a very good comparison; New Horizons didn't get the gravity boost of the Voyagers and so isn't going as fast; and it doesn't have an engine, so is coasting all the way. An ion drive would have improved the flight time. But it is powered by an RTG, and it has reached solar escape velocity. That makes it one of the only eight man-made objects to do so.

  14. Re:Unless I'm mistaken on Voyager 2 Set to Reach Termination Shock · · Score: 1

    ...and you can get the data sets here. Admittedly, there's not a lot you can do with it if you're not a highly specialised astronomer and plasma physicist, but it's cool that it's available, nevertheless.

  15. Re:How much is that in ... on Maglev On the Drawing Boards · · Score: 2, Informative

    The official Pentagon figures are 6.8 billion dollars a month, or approximately 9 million dollars an hour. Which means that one hundred million dollars would pay for slightly more than eleven hours worth of war.

  16. Re:Ewoks on When Did Star Wars Jump the Shark? · · Score: 1

    Its likely that a someone held out the white flag and called truce within a few minutes of it being confirmed that the Big Round Thing II was indeed blown up and that the Emperor and Vader were presumed dead.

    According to those bits of the Official Continuity that actually make sense (mostly written by Timothy Zahn), what actually happened was that the Imperial forces, demoralised but not yet losing (Star Destroyers are pretty powerful), withdrew in good order. However, without the Emperor's influence, the various leaders started bickering and the fleet quickly fragmented. Some surrendered, some regrouped around various prestigious leaders (especially Thrawn). The Battle of Endor was not the end of the war, which ground on for years, but it was the turning point. Coruscant, the imperial capital, was liberated a couple of years later, and the New Republic was founded five years after the battle. The Imperial Remnant eventually signed a peace treaty with the New Republic about fifteen years later.

    Yes, I'm aware I'm far too interested in this stuff.

    Look here if you want to know more, but be warned that the Star Wars Expanded Universe is full of crap. They've tried to combine every ghastly third-rate novel and comic book that played but-what-really-happened-was-this and the result is almost incoherent. Palpatine was brought back to life and killed off about a dozen times. The Empire came back and blew up Coruscant. Alien invaders came along and blew up Coruscant. The Empire came back again, and blew up Coruscant. (If you ever find yourself living in the Star Wars universe, don't live on Coruscant.) The Death Star II was operated in secret by the Droid Rebellion... with Star Wars canon, you have to be very firm about where you draw the line; I do so when I stop being entertained by it.

  17. Re:It became a Punch and Judy show, a really bad o on When Did Star Wars Jump the Shark? · · Score: 1

    Now take Episode 1. We know who the baddy is, Palpatine. We KNOW him to be the future emperor, no suprise there. We also KNOW him to be evil. The prequels don't even pretend he is perhaps someone who is trying to create a better future but gets corrupted along the way. Palpatine is evil, end of story.

    There was a rumour going round for a while that the Emperor was not, in fact, Palpatine... but was instead Palpatine's clone.

    Despite totally shooting dead any post-film continuity, such as Timothy Zahn's excellent novels (and a lot of other really bad ones), that would have actually worked as a overall theme. It allows the Clone Wars to actually work... and then go horribly wrong. It moves the good vs. evil struggle away from Anakin (who is currently good, but we know is going to turn out evil) and on to Palpatine (who we think is going to be evil, but in the new continuity actually turns out to be good). Suddenly, there's a whole new storyline of Palpatine vs. Palpatine's evil twin. And we, the audience, don't know who is who. It's actually interesting, which the existing plots aren't.

    But nah, he doesn't do it. Instead he piles up a big heap of clichés and expects us to like them. Bah.

  18. The very first scene on When Did Star Wars Jump the Shark? · · Score: 1

    For me, it was that first piece of dialogue with Obi-Wan and Qui-Gon. I listened to the clunky phrasing and complete absence of chemistry with this horrible sinking feeling. The original movies had scripts that made you feel like the characters were talking to each other. _tPM_ had scripts that made you feel like the actors were talking at each other. I mean:

    OBI-WAN : I have a bad feeling about this.
    QUI-GON : I don't sense anything.
    OBI-WAN : It's not about the mission, Master, it's something... elsewhere... elusive.
    QUI-GON : Don't center on your anxiety, Obi-Wan. Keep your concentration here and now where it belongs.
    OBI-WAN : Master Yoda says I should be mindful of the future...
    QUI-GON : ...but not at the expense of the moment. Be mindful of the living Force, my young Padawan.

    Ugh. This is a master Jedi talking to his apprentice. They have a close personal relationship. They're going to talk like they know each other, not in formal platitudes and lectures. Compare with Yoda and Luke on Dagobah --- or even the wonderful endless bickering between Luke, Han and Leia... now, that was good dialogue. This stuff? Blah. It's all too obviously glue to stick the actions scenes together.

    Basically, the tPM script was just bad.

    Obligatory VGCats comic reference.

  19. Re:emulators? on MIT Releases the Source of MULTICS, Father of UNIX · · Score: 2, Informative

    Are you just pretending that you forgot about the GB of RAM that comes as standard on on MacBook Pros, or do you really think that RAM is irrelevant to emulation?

    Of course it is. If you've got enough swap. Which you can plug into the Palm's USB connector.

  20. Only in America on OLPC Launches Buy One, Give One Free Program · · Score: 1

    (America in the geographical sense, of course...)

    I'd love to buy one. It looks great; not only would I find it useful as well as being a really cool toy, but I think this is a cause highly worth supporting. Alas, the offer is only valid for people in continental North America (plus island states of the USA). Since I live in the UK, I'm stuffed.

    Hopefully at some stage they'll run a European G1G1 programme.

    (Actually, maybe the G1G1 programme will show enough demand that some budding entrepeneur will order a million and start selling them in high-street stores. The OLPC would make a superb alternative to these 'learning laptop' toys.)

  21. Re:Why give notice, then?Resign effective immediat on Microsoft's Treatment of Google Defectors · · Score: 1

    Giving notice is a courtesy to the company and it must be earned.

    Where I work, it's a contractual obligation. I am required to give notice if I wish to resign. Likewise, the company is required to give me notice if they want to make me redundant. There are some get-out clauses: I can trade unused holiday time for notice, and the company can trade money for notice (so that if they want me to leave right now, they have to pay me substantially more [in addition to the statutory redundancy package; I forget how much that is --- three month's salary?].)

    What's fairly normal in IT is that when giving or given notice, you finish up your job and then go home. For the remainder of your notice period you don't come in to work, although you still get paid full salary.

    Of course, I live in the UK, which has substantially better labour laws than the US...

  22. Re:S.E.T.I on Is SETI Worth It? · · Score: 3, Informative

    The total of SETI's 'wasteful' expenses is like 14 million a year.

    $14 million dollars would fund the Iraq war for 88 minutes (based on the official Pentagon 'burn rate' estimate of $6.8 billion a month).

  23. Re:Enormous demand equals lower prices? on Hard Drive Prices Hitting New Lows · · Score: 1

    Your contention that prices will fall is simply untrue.

    But they do fall. Always. (Well, for mass produced goods.) The unit cost of mass producing an item falls as the number of items being produced rises --- this is what mass production is for. Therefore, if demand rises, then eventually (as you say) more production capability will be built and supply will increase --- but now they're being produced more efficiently, therefore they're available at a lower price. The causality chain is clear: if demand goes up, prices will eventually go down. There are a lot of intermediate stages, such as amortisation of the new production facilities, but that's what happens.

  24. Re:flag on Japanese Probe Returns First HD Video of the Moon · · Score: 2, Insightful

    That thing's been there for 40 years, it's not going anywhere. Though by the looks of it, it'll be another 40 years before another American astronaut even comes close to touching it.

    That's okay --- just ask the Chinese to take a picture of it for you...

  25. Re:Are other Linux estimates wrong? on BBC Backpedals On Linux Audience Figures · · Score: 1

    I would assume that the BBC did not invent its own method of measuring web traffic, but uses some package or service.

    Actually, the BBC's web presence is so vast --- it's one of the biggest websites in the world, they get so much traffic that the Slashdot Effect gets lost in the noise --- that they have to use quite a lot of custom software. I wouldn't be at all surprised if they were using their own traffic analysis system.