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  • The State of the Internet -- Retail Edition

    - by David Dorf
    Over at Business Insider, there's a great presentation on the State of the Internet done in the Mary Meeker style.  Its 138 slides so I took the liberty of condensing it down to the 15 slides that directly apply to the retail industry.  However, I strongly recommend looking at the entire deck when you have time.  And while you're at it, Business Insider just launched a retail portal that's dedicated to retail industry content.  Please check it out as well.  My take-aways are below after the slide show. &amp;amp;amp;amp;lt;span id=&amp;amp;amp;amp;quot;XinhaEditingPostion&amp;amp;amp;amp;quot;&amp;amp;amp;amp;gt;&amp;amp;amp;amp;lt;/span&amp;amp;amp;amp;gt; [Source: Business Insider] Here are a few things I took away from the statistics: Facebook and Twitter are in their infancy.  While all retailers should have social programs, search is still the driver and therefore should receive the lions share of investment.  Facebook referrals are up 92% year-over-year, but Google still does 80% of the referrals. E-commerce continues to grow at breakneck speed, but in-store commerce is still king. Stores are not showrooms yet.  And social commerce pure-plays like Gilt and Groupon are tiny but worthy of some attention. There are more smartphones than PCs on the internet, and the disparity will continue to grow. PC growth will be flat and Tablet use will continue to grow. Mobile accounts for 12% of all internet traffic. A quarter of smartphone sales come from China, so anyone with a presence there better have a strong mobile strategy. 38% of people have used their smartphone to make a purchase, and many use their smartphones inside stores.  Smartphones are a critical consumer tool for shopping. Mobile is starting to drive significant traffic to e-commerce sites, especially tablets.  Tablet strategies are crucial for retailers. Mobile payments from the likes of Paypal and Square are growing quickly.  It will be interesting to see how NFC plays in this area. Mobile operating systems are losing market share to iOS and Android.  I wonder in Microsoft can finally make a dent? The internet is being dominated by mobile devices, and retailers had better have a strong mobile strategy to meet consumer demand.

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  • Revert scan state when prompting for variable values

    - by Dave Jarvis
    How do you detect the current SCAN state and revert it after changing it? An exerpt from the script in question: SET SCAN OFF SET ECHO ON SET SQLBLANKLINES ON SET SCAN ON UPDATE TABLE_NAME SET CREATED_BY = &&created_by; SET SCAN OFF The problem is that if the script doesn't have the first line (SET SCAN OFF), then the code to prompt the user should not turn the SCAN state off. In pseudocode, we'd like to do the following: SET SCAN OFF SET ECHO ON SET SQLBLANKLINES ON PUSH SCAN STATE SET SCAN ON UPDATE TABLE_NAME SET CREATED_BY = &&created_by; POP SCAN STATE The psudeocode PUSH SCAN STATE remembers the state so that if the code is altered by removing the first line, the rest of the script still works as expected.

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  • Why does my finite state machine take so long to execute?

    - by BillyONeal
    Hello all :) I'm working on a state machine which is supposed to extract function calls of the form /* I am a comment */ //I am a comment perf("this.is.a.string.which\"can have QUOTES\"", 123456); where the extracted data would be perf("this.is.a.string.which\"can have QUOTES\"", 123456); from a file. Currently, to process a 41kb file, this process is taking close to a minute and a half. Is there something I'm seriously misunderstanding here about this finite state machine? #include <boost/algorithm/string.hpp> std::vector<std::string> Foo() { std::string fileData; //Fill filedata with the contents of a file std::vector<std::string> results; std::string::iterator begin = fileData.begin(); std::string::iterator end = fileData.end(); std::string::iterator stateZeroFoundLocation = fileData.begin(); std::size_t state = 0; for(; begin < end; begin++) { switch (state) { case 0: if (boost::starts_with(boost::make_iterator_range(begin, end), "pref(")) { stateZeroFoundLocation = begin; begin += 4; state = 2; } else if (*begin == '/') state = 1; break; case 1: state = 0; switch (*begin) { case '*': begin = boost::find_first(boost::make_iterator_range(begin, end), "*/").end(); break; case '/': begin = std::find(begin, end, L'\n'); } break; case 2: if (*begin == '"') state = 3; break; case 3: switch(*begin) { case '\\': state = 4; break; case '"': state = 5; } break; case 4: state = 3; break; case 5: if (*begin == ',') state = 6; break; case 6: if (*begin != ' ') state = 7; break; case 7: switch(*begin) { case '"': state = 8; break; default: state = 10; break; } break; case 8: switch(*begin) { case '\\': state = 9; break; case '"': state = 10; } break; case 9: state = 8; break; case 10: if (*begin == ')') state = 11; break; case 11: if (*begin == ';') state = 12; break; case 12: state = 0; results.push_back(std::string(stateZeroFoundLocation, begin)); }; } return results; } Billy3

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  • Disabling itemrenderer Hovered state

    - by duder
    My itemrenderer has 2 custom states, no hovered state, and no normal state <s:states> <s:State name="state1" /> <s:State name="state2" /> </s:states> When I initialize it, I force it to go to state2. The problem is that when it's hovered over, it relapses back to the first state state1. It's kind of weird since I don't really have a hovered state. Anyone knows how to prevent this from happening? maybe by somehow disabling the hover effect?

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  • Flex4 Application state in a custom component

    - by itarato
    Hi, I'm porting my Flex3 app to Flex4 (FlashBuilder4). I get the whole new state concept, except one thing. In a custom component (separate mxml file) I'm using the main level Application's state. In Flex3 it was: <mx:State name="only_view_mode"> <mx:RemoveChild target="{myComponent.button1}" /> </mx:State> In Flex4 it should be something like that: <mx:State name="only_view_mode" /> and <mx:LinkButton id="button1" excludeFrom="???" /> My question is: how can I access to an Application state from a component? I checked the official reference (http://www.adobe.com/go/learn_flex4_alldocumentation_en) and Google of course but without any success. Thanks in advance

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  • Is it bad practice to change state inside of an if statement?

    - by Benjamin
    I wrote some code that looks similar to the following: String SKIP_FIRST = "foo"; String SKIP_SECOND = "foo/bar"; int skipFooBarIndex(String[] list){ int index; if (list.length >= (index = 1) && list[0].equals(SKIP_FIRST) || list.length >= (index = 2) && (list[0] + "/" + list[1]).equals(SKIP_SECOND)){ return index; } return 0; } String[] myArray = "foo/bar/apples/peaches/cherries".split("/"); print(skipFooBarIndex(myArray); This changes state inside of the if statement by assigning index. However, my coworkers disliked this very much. Is this a harmful practice? Is there any reason to do it?

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  • [Flex] Modify components that is not included in the current state?

    - by user322896
    In Flex 4, is it possible to modify components that is not include in the current state? For example, I have labelA included in stateA, how do I change the label text in stateB? If I directly change the label text in stateB, I'll get an null reference error message. One workaround is to include labelA in all states, and set it to be invisible in states other than stateA. However, if the number of this kind of component goes too large, the work becomes tedious, and also I don't think it's reasonable to include unnecessary UI components in unrelated states. Is there better solution for this situation? Thanks! Regards

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  • Is Perl's flip-flop operator bugged? It has global state, how can I reset it?

    - by Evan Carroll
    I'm dismayed. Ok, so this was probably the most fun perl bug I've ever found. Even today I'm learning new stuff about perl. Essentially, the flip-flop operator .. which returns false until the left-hand-side returns true, and then true until the right-hand-side returns false keep global state (or that is what I assume.) My question is can I reset it, (perhaps this would be a good addition to perl4-esque hardly ever used reset())? Or, is there no way to use this operator safely? I also don't see this (the global context bit) documented anywhere in perldoc perlop is this a mistake? Code use feature ':5.10'; use strict; use warnings; sub search { my $arr = shift; grep { !( /start/ .. /never_exist/ ) } @$arr; } my @foo = qw/foo bar start baz end quz quz/; my @bar = qw/foo bar start baz end quz quz/; say 'first shot - foo'; say for search \@foo; say 'second shot - bar'; say for search \@bar; Spoiler $ perl test.pl first shot foo bar second shot

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  • Oracle HRMS API – Update Employee State Tax Rule

    - by PRajkumar
    API --  pay_state_tax_rule_api.update_state_tax_rule Example --   DECLARE      lc_dt_ud_mode                       VARCHAR2(100)   := NULL;      ln_assignment_id                  NUMBER                  := 33561;      ln_object_version_number  NUMBER                  := 1;      ld_effective_start_date          DATE;      ld_effective_end_date            DATE;      lb_correction                            BOOLEAN;      lb_update                                  BOOLEAN;      lb_update_override                BOOLEAN;      lb_update_change_insert    BOOLEAN; BEGIN     -- Find Date Track Mode     -- --------------------------------      dt_api.find_dt_upd_modes      (   p_effective_date                 => TO_DATE('12-JUN-2011'),          p_base_table_name          => 'PER_ALL_ASSIGNMENTS_F',          p_base_key_column         => 'ASSIGNMENT_ID',          p_base_key_value             => ln_assignment_id,          -- Output data elements          -- --------------------------------         p_correction                          => lb_correction,         p_update                                => lb_update,         p_update_override              => lb_update_override,         p_update_change_insert   => lb_update_change_insert     );        IF ( lb_update_override = TRUE OR lb_update_change_insert = TRUE )    THEN       -- UPDATE_OVERRIDE       -- --------------------------------       lc_dt_ud_mode := 'UPDATE_OVERRIDE';    END IF;      IF ( lb_correction = TRUE )    THEN       -- CORRECTION       -- ----------------------      lc_dt_ud_mode := 'CORRECTION';    END IF;      IF ( lb_update = TRUE )    THEN        -- UPDATE        -- --------------        lc_dt_ud_mode := 'UPDATE';    END IF;      -- Update State Tax Rule    -- ---------------------------------     pay_state_tax_rule_api.update_state_tax_rule     (     -- Input data elements           -- ------------------------------           p_effective_date                        => TO_DATE('20-JUN-2011'),           p_datetrack_update_mode   => lc_dt_ud_mode,           p_emp_state_tax_rule_id      => 8455,           p_withholding_allowances  => 100,           p_sit_additional_tax               => 10,           p_sit_exempt                              => 'N',           -- Output data elements           -- --------------------------------           p_object_version_number      => ln_object_version_number,           p_effective_start_date              => ld_effective_start_date,           p_effective_end_date               => ld_effective_end_date      );  COMMIT; EXCEPTION        WHEN OTHERS THEN                        ROLLBACK;                        dbms_output.put_line(SQLERRM); END; / SHOW ERR;  

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  • Oracle HRMS API – Create Employee State Tax Rule

    - by PRajkumar
    API --  pay_state_tax_rule_api.create_state_tax_rule Example --   DECLARE     lc_dt_ud_mode                     VARCHAR2(100)     := NULL;      ln_assignment_id                 NUMBER                    := 33561;     lb_correction                            BOOLEAN;      lb_update                                 BOOLEAN;      lb_update_override               BOOLEAN;      lb_update_change_insert    BOOLEAN;     ln_emp_state_tax_rule_id   PAY_US_EMP_STATE_TAX_RULES_F.EMP_STATE_TAX_RULE_ID%TYPE;     ln_object_version_number  NUMBER;      ld_effective_start_date          DATE;      ld_effective_end_date           DATE; BEGIN       -- Find Date Track Mode       -- --------------------------------         dt_api.find_dt_upd_modes         (     p_effective_date                  => TO_DATE('12-JUN-2011'),               p_base_table_name            => 'PER_ALL_ASSIGNMENTS_F',               p_base_key_column          => 'ASSIGNMENT_ID',               p_base_key_value              => ln_assignment_id,               -- Output data elements               -- --------------------------------              p_correction                           => lb_correction,              p_update                                => lb_update,              p_update_override              => lb_update_override,              p_update_change_insert   => lb_update_change_insert        );      IF ( lb_update_override = TRUE OR lb_update_change_insert = TRUE )    THEN       -- UPDATE_OVERRIDE       -- ---------------------------------       lc_dt_ud_mode := 'UPDATE_OVERRIDE';    END IF;      IF ( lb_correction = TRUE )    THEN       -- CORRECTION       -- ----------------------       lc_dt_ud_mode := 'CORRECTION';    END IF;      IF ( lb_update = TRUE )    THEN       -- UPDATE       -- --------------       lc_dt_ud_mode := 'UPDATE';    END IF;      -- Create Employee State Tax Rule    -- -----------------------------------------------     pay_state_tax_rule_api.create_state_tax_rule     (    -- Input Parameters          -- --------------------------          p_effective_date                         => TO_DATE('15-JUN-2011'),          p_default_flag                            => 'Y',          p_assignment_id                      => 33561,          p_state_code                               => '05',          -- Output Parameters          -- ----------------------------         p_emp_state_tax_rule_id        => ln_emp_state_tax_rule_id,         p_object_version_number       => ln_object_version_number,         p_effective_start_date               => ld_effective_start_date,         p_effective_end_date                => ld_effective_end_date   );    COMMIT; EXCEPTION           WHEN OTHERS THEN                        ROLLBACK;                         dbms_output.put_line(SQLERRM); END; / SHOW ERR;  

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  • Another question about handling game states

    - by Eva
    I'm making a game designed with the entity-component paradigm that uses systems to communicate between components as explained here. I've reached the point in my development that I need to add game states (such as paused, playing, level start, round start, game over, etc.), but I'm not sure how to do it with my framework. I've looked at this code example on game states which everyone seems to reference, but I don't think it fits with my framework. It seems to have each state handling its own drawing and updating. My framework has a SystemManager that handles all the updating using systems. For example, here's my RenderingSystem class: public class RenderingSystem extends GameSystem { private GameView gameView_; /** * Constructor * Creates a new RenderingSystem. * @param gameManager The game manager. Used to get the game components. */ public RenderingSystem(GameManager gameManager) { super(gameManager); } /** * Method: registerGameView * Registers gameView into the RenderingSystem. * @param gameView The game view registered. */ public void registerGameView(GameView gameView) { gameView_ = gameView; } /** * Method: triggerRender * Adds a repaint call to the event queue for the dirty rectangle. */ public void triggerRender() { Rectangle dirtyRect = new Rectangle(); for (GameObject object : getRenderableObjects()) { GraphicsComponent graphicsComponent = object.getComponent(GraphicsComponent.class); dirtyRect.add(graphicsComponent.getDirtyRect()); } gameView_.repaint(dirtyRect); } /** * Method: renderGameView * Renders the game objects onto the game view. * @param g The graphics object that draws the game objects. */ public void renderGameView(Graphics g) { for (GameObject object : getRenderableObjects()) { GraphicsComponent graphicsComponent = object.getComponent(GraphicsComponent.class); if (!graphicsComponent.isVisible()) continue; GraphicsComponent.Shape shape = graphicsComponent.getShape(); BoundsComponent boundsComponent = object.getComponent(BoundsComponent.class); Rectangle bounds = boundsComponent.getBounds(); g.setColor(graphicsComponent.getColor()); if (shape == GraphicsComponent.Shape.RECTANGULAR) { g.fill3DRect(bounds.x, bounds.y, bounds.width, bounds.height, true); } else if (shape == GraphicsComponent.Shape.CIRCULAR) { g.fillOval(bounds.x, bounds.y, bounds.width, bounds.height); } } } /** * Method: getRenderableObjects * @return The renderable game objects. */ private HashSet<GameObject> getRenderableObjects() { return gameManager.getGameObjectManager().getRelevantObjects( getClass()); } } Also all the updating in my game is event-driven. I don't have a loop like theirs that simply updates everything at the same time. I like my framework because it makes it easy to add new GameObjects, but doesn't have the problems some component-based designs encounter when communicating between components. I would hate to chuck it just to get pause to work. Is there a way I can add game states to my game without removing the entity-component design? Does the game state example actually fit my framework, and I'm just missing something?

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  • How should I structure my turn based engine to allow flexibility for players/AI and observation?

    - by Reefpirate
    I've just started making a Turn Based Strategy engine in GameMaker's GML language... And I was cruising along nicely until it came time to handle the turn cycle, and determining who is controlling what player, and also how to handle the camera and what is displayed on screen. Here's an outline of the main switch happening in my main game loop at the moment: switch (GameState) { case BEGIN_TURN: // Start of turn operations/routines break; case MID_TURN: switch (PControlledBy[Turn]) { case HUMAN: switch (MidTurnState) { case MT_SELECT: // No units selected, 'idle' UI state break; case MT_MOVE: // Unit selected and attempting to move break; case MT_ATTACK: break; } break; case COMPUTER: // AI ROUTINES GO HERE break; case OBSERVER: // OBSERVER ROUTINES GO HERE break; } break; case END_TURN: // End of turn routines/operations, and move Turn to next player break; } Now, I can see a couple of problems with this set-up already... But I don't have any idea how to go about making it 'right'. Turn is a global variable that stores which player's turn it is, and the BEGIN_TURN and END_TURN states make perfect sense to me... But the MID_TURN state is baffling me because of the things I want to happen here: If there are players controlled by humans, I want the AI to do it's thing on its turn here, but I want to be able to have the camera follow the AI as it makes moves in the human player's vision. If there are no human controlled player's, I'd like to be able to watch two or more AI's battle it out on the map with god-like 'observer' vision. So basically I'm wondering if there are any resources for how to structure a Turn Based Strategy engine? I've found lots of writing about pathfinding and AI, and those are all great... But when it comes to handling the turn structure and the game states I am having trouble finding any resources at all. How should the states be divided to allow flexibility between the players and the controllers (HUMAN, COMPUTER, OBSERVER)? Also, maybe if I'm on the right track I just need some reassurance before I lay down another few hundred lines of code...

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  • dotRAS Disconnected State not triggered

    - by JD
    Can someone give me a heads up... I'm trying to use the dotRAS .NET control, and this code to change the value of internetConnected (boolean) using an event handler... But it seems that the state RasConnectionState.Disconnected is not triggered by dotRAS hangup().. Any ideas? Am I doing it totally wrong... or have I managed to find a bug? public class USBModem { // private vars private RasDialer dialer = new RasDialer(); private bool internetConnected = false; /// <summary> /// Default constructor for USBModem /// </summary> public USBModem() { // Add Events for dialer dialer.StateChanged += new EventHandler<StateChangedEventArgs>(dialer_StateChanged); } void dialer_StateChanged(object sender, StateChangedEventArgs e) { // Handle state changes here switch (e.State) { case RasConnectionState.Connected: internetConnected = true; Console.WriteLine(e.State.ToString()); break; case RasConnectionState.Disconnected: internetConnected = false; Console.WriteLine(e.State.ToString()); break; default: Console.WriteLine("INFO -> Unhandled state: " + e.State.ToString()); break; } } public void ConnectInternet(string connectionName) { // Dial dialer.PhoneBookPath = RasPhoneBook.GetPhoneBookPath(RasPhoneBookType.AllUsers); dialer.EntryName = connectionName; dialer.DialAsync(); } public void DisconnectInternet() { foreach (RasConnection connection in dialer.GetActiveConnections()) { connection.HangUp(); } } }

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  • Threading extra state through a parser in Scala

    - by Travis Brown
    I'll give you the tl;dr up front I'm trying to use the state monad transformer in Scalaz 7 to thread extra state through a parser, and I'm having trouble doing anything useful without writing a lot of t m a -> t m b versions of m a -> m b methods. An example parsing problem Suppose I have a string containing nested parentheses with digits inside them: val input = "((617)((0)(32)))" I also have a stream of fresh variable names (characters, in this case): val names = Stream('a' to 'z': _*) I want to pull a name off the top of the stream and assign it to each parenthetical expression as I parse it, and then map that name to a string representing the contents of the parentheses, with the nested parenthetical expressions (if any) replaced by their names. To make this more concrete, here's what I'd want the output to look like for the example input above: val target = Map( 'a' -> "617", 'b' -> "0", 'c' -> "32", 'd' -> "bc", 'e' -> "ad" ) There may be either a string of digits or arbitrarily many sub-expressions at a given level, but these two kinds of content won't be mixed in a single parenthetical expression. To keep things simple, we'll assume that the stream of names will never contain either duplicates or digits, and that it will always contain enough names for our input. Using parser combinators with a bit of mutable state The example above is a slightly simplified version of the parsing problem in this Stack Overflow question. I answered that question with a solution that looked roughly like this: import scala.util.parsing.combinator._ class ParenParser(names: Iterator[Char]) extends RegexParsers { def paren: Parser[List[(Char, String)]] = "(" ~> contents <~ ")" ^^ { case (s, m) => (names.next -> s) :: m } def contents: Parser[(String, List[(Char, String)])] = "\\d+".r ^^ (_ -> Nil) | rep1(paren) ^^ ( ps => ps.map(_.head._1).mkString -> ps.flatten ) def parse(s: String) = parseAll(paren, s).map(_.toMap) } It's not too bad, but I'd prefer to avoid the mutable state. What I want Haskell's Parsec library makes adding user state to a parser trivially easy: import Control.Applicative ((*>), (<$>), (<*)) import Data.Map (fromList) import Text.Parsec paren = do (s, m) <- char '(' *> contents <* char ')' h : t <- getState putState t return $ (h, s) : m where contents = flip (,) [] <$> many1 digit <|> (\ps -> (map (fst . head) ps, concat ps)) <$> many1 paren main = print $ runParser (fromList <$> paren) ['a'..'z'] "example" "((617)((0)(32)))" This is a fairly straightforward translation of my Scala parser above, but without mutable state. What I've tried I'm trying to get as close to the Parsec solution as I can using Scalaz's state monad transformer, so instead of Parser[A] I'm working with StateT[Parser, Stream[Char], A]. I have a "solution" that allows me to write the following: import scala.util.parsing.combinator._ import scalaz._, Scalaz._ object ParenParser extends ExtraStateParsers[Stream[Char]] with RegexParsers { protected implicit def monadInstance = parserMonad(this) def paren: ESP[List[(Char, String)]] = (lift("(" ) ~> contents <~ lift(")")).flatMap { case (s, m) => get.flatMap( names => put(names.tail).map(_ => (names.head -> s) :: m) ) } def contents: ESP[(String, List[(Char, String)])] = lift("\\d+".r ^^ (_ -> Nil)) | rep1(paren).map( ps => ps.map(_.head._1).mkString -> ps.flatten ) def parse(s: String, names: Stream[Char]) = parseAll(paren.eval(names), s).map(_.toMap) } This works, and it's not that much less concise than either the mutable state version or the Parsec version. But my ExtraStateParsers is ugly as sin—I don't want to try your patience more than I already have, so I won't include it here (although here's a link, if you really want it). I've had to write new versions of every Parser and Parsers method I use above for my ExtraStateParsers and ESP types (rep1, ~>, <~, and |, in case you're counting). If I had needed to use other combinators, I'd have had to write new state transformer-level versions of them as well. Is there a cleaner way to do this? I'd love to see an example of a Scalaz 7's state monad transformer being used to thread state through a parser, but Scala 6 or Haskell examples would also be useful.

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  • Country/City/state validation

    - by M.M.H.Masud
    I want to do the following things using PHP and jQuery https://www.careerbuilder.com/share/register.aspx?sc_cmp1=JS_LoginASPX_RegNow Steps Select a country from a dropdown list. The city dropdown list will fillup automatically with the list of cities of the selected country. If state is available for that country then state list will be visible with all state list of that country. Then I need to validate the selected city, state and country. Do you have any ideas? Thanks in advance

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  • State server in webfarm scenario?

    - by Curtis White
    This is a fairly basic question about state server but assume there are 2 servers behind a load balancer. How do I configure the session state server? So, I have machine1 and machine2. I would assume that I would need to install the state server on 1 machine only and then use the internal IP to refer to that machine. Is this correct? As oppose too, I would not install state server on both machines.

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  • <a> with an inner <span> not triggering :active state in IE

    - by Adam Singer
    I want to style the :active state of a button that is represented by an . The tag has an inner (beacuse I want to add an icon to this button). I notice the :active state is triggered properly in everything but Internet Explorer. In IE, it appears that the area around the (the 's padding) triggers that :active state, but when clicking directly on the text within the , the :active state is not triggered. Is there a way to fix this without resorting to Javascript?

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  • Android reset activity component state on navigation back

    - by Aure77
    I have 2 activities in my application. In activity1, I set some configuration and I modify the state of some component (ex: set button state disabled). And I navigate to activity2. In activity2 I do some stuff and at end, I finish this activity and come back to activity1. But In activity1, my components state are the same when I leave this activity. How to reset the components state with valuesdeclared in XML file (layout) ?

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  • clojure.algo.monad strange m-plus behaviour with parser-m - why is second m-plus evaluated?

    - by Mark Fisher
    I'm getting unexpected behaviour in some monads I'm writing. I've created a parser-m monad with (def parser-m (state-t maybe-m)) which is pretty much the example given everywhere (here, here and here) I'm using m-plus to act a kind of fall-through query mechanism, in my case, it first reads values from a cache (database), if that returns nil, the next method is to read from "live" (a REST call). However, the second value in the m-plus list is always called, even though its value is disgarded (if the cache hit was good) and the final return is that of the first monadic function. Here's a cutdown version of the issue i'm seeing, and some solutions I found, but I don't know why. My questions are: Is this expected behaviour or a bug in m-plus? i.e. will the 2nd method in a m-plus list always be evaluated if the first item returns a value? Minor in comparison to the above, but if i remove the call _ (fetch-state) from checker, when i evaluate that method, it prints out the messages for the functions the m-plus is calling (when i don't think it should). Is this also a bug? Here's a cut-down version of the code in question highlighting the problem. It simply checks key/value pairs passed in are same as the initial state values, and updates the state to mark what it actually ran. (ns monods.monad-test (:require [clojure.algo.monads :refer :all])) (def parser-m (state-t maybe-m)) (defn check-k-v [k v] (println "calling with k,v:" k v) (domonad parser-m [kv (fetch-val k) _ (do (println "k v kv (= kv v)" k v kv (= kv v)) (m-result 0)) :when (= kv v) _ (do (println "passed") (m-result 0)) _ (update-val :ran #(conj % (str "[" k " = " v "]"))) ] [k v])) (defn filler [] (println "filler called") (domonad parser-m [_ (fetch-state) _ (do (println "filling") (m-result 0)) :when nil] nil)) (def checker (domonad parser-m [_ (fetch-state) result (m-plus ;; (filler) ;; intitially commented out deliberately (check-k-v :a 1) (check-k-v :b 2) (check-k-v :c 3))] result)) (checker {:a 1 :b 2 :c 3 :ran []}) When I run this as is, the output is: > (checker {:a 1 :b 2 :c 3 :ran []}) calling with k,v: :a 1 calling with k,v: :b 2 calling with k,v: :c 3 k v kv (= kv v) :a 1 1 true passed k v kv (= kv v) :b 2 2 true passed [[:a 1] {:a 1, :b 2, :c 3, :ran ["[:a = 1]"]}] I don't expect the line k v kv (= kv v) :b 2 2 true to show at all. The first function to m-plus (as seen in the final output) is what is returned from it. Now, I've found if I pass a filler into m-plus that does nothing (i.e. uncomment the (filler) line) then the output is correct, the :b value isn't evaluated. If I don't have the filler method, and make the first method test fail (i.e. change it to (check-k-v :a 2) then again everything is good, I don't get a call to check :c, only a and b are tested. From my understanding of what the state-t maybe-m transformation is giving me, then the m-plus function should look like: (defn m-plus [left right] (fn [state] (if-let [result (left state)] result (right state)))) which would mean that right isn't called unless left returns nil/false. I'd be interested to know if my understanding is correct or not, and why I have to put the filler method in to stop the extra evaluation (whose effects I don't want to happen). Apologies for the long winded post!

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  • Improving the state of the art in API documentation sites

    - by Daniel Cazzulino
    Go straight to the site if you want: http://nudoq.org. You can then come back and continue reading :) Compare some of the most popular NuGet packages API documentation sites: Json.NET EntityFramework NLog Autofac You see the pattern? Huge navigation tree views, static content with no comments/community content, very hard (if not impossible) to search/filter, etc. These are the product of automated tools that have been developed years ago, in a time where CHM help files were common and even expected from libraries. Nowadays, most of the top packages in NuGet.org don’t even provide an online documentation site at all: it’s such a hassle for such a crappy user experience in the end! Good news is that it doesn’t have to be that way. Introducing NuDoq A lot has changed since those early days of .NET. We now have NuGet packages and the awesome channel that is ...Read full article

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  • Can frequent state changes decrease rendering performance?

    - by Miro
    Can frequent texture and shader binding decrease rendering performance? "Frequent" binding example: for object for material in object render part of object using that material "Low count" binding example: for material for object in material render part of object using that material I'm planning to use an octree later and with this "low count" method of rendering it can drastically increase memory consumption. So is it good idea?

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  • unit testing variable state explicit tests in dynamically typed languages

    - by kris welsh
    I have heard that a desirable quality of unit tests is that they test for each scenario independently. I realised whilst writing tests today that when you compare a variable with another value in a statement like: assertEquals("foo", otherObject.stringFoo); You are really testing three things: The variable you are testing exists and is within scope. The variable you are testing is the expected type. The variable you are testing's value is what you expect it to be. Which to me raises the question of whether you should test for each of these implicitly so that a test fail would occur on the specific line that tests for that problem: assertTrue(stringFoo); assertTrue(stringFoo.typeOf() == "String"); assertEquals("foo", otherObject.stringFoo); For example if the variable was an integer instead of a string the test case failure would be on line 2 which would give you more feedback on what went wrong. Should you test for this kind of thing explicitly or am i overthinking this?

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  • Technical Presentation: State of the LDom @ 3.1

    - by uwes
    Announcing a new technical presentation covering Oracle VM for SPARC on eSTEP portal. For those of you, who want to have a brief technical overview to OVM for SPARC (aka LDOMs) have a look into Stefan Hinker´s just finished presentation. Based on the current 3.1 release, Stefan covers the following topics: LDoms – Basics of the SPARC Hypervisor Partitioned Hardware – Virtualized PCIe Virtual IO Domain Configurations & Recommendations Management The presentation can be downloaded from eSTEP portal. URL: http://launch.oracle.com/ PIN: eSTEP_2011 The material can be found under tab eSTEP Download.

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