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  • Flash SWF not initializing until visible - can I force them to initialize?

    - by Jason
    I have an application that needs to render about 100 flash graphs (as well as other DOM stuff) in a series of rows that vertically extend many times beyond the current visible window - in other words, the users have to scroll down see see all the different graphs. This application is also dynamic and when a user changes a value in the DOM (anywhere on the page) it will need to propagate that change to all the Flash graphs at the same time. So I setup all the externalInterface callbacks and was careful to not let any JS start going until the ever-so-important "flashIsReady" call and...it worked great until I tried to update() the existing swf's with new data. Here was the behavior: - All the swfs load (initially) in both IE/Fox = good. - Updating swfs with new content works in IE but not in Fox = not good - Updating swfs with new content works in Fox --ONLY IF-- I scrolled down to the bottom of the page, then back to the top -- BEFORE -- I triggered an update(). So then I started tracing out each time a swf called the JS to say "flash is ready" and I realized, Firfox only renders swfs as they become visible. And To be honest - that's fine and actually, I am pretty sure that IE does this too. But the problem is that not only does Firefox not initialize the swf, Firefox doesn't even acknowledge the swf exists (expect for after onload) if it has not yet been visible. And the proof is that you get JS errors saying: "[FlashDOMID].FlashMethod is not a function". However, scroll down a little, wait until its visible and suddenly the trace starts lighting up "Flash Ready", "Flash Ready", "Flash Ready" and once they are all ready, everything works fine. Someone told me that FF does not init swf's until visible - can I force it? I can post code if you need...but its pretty heavy (hard to strip out the relevant from the rest) and I would like to avoid it (for your sakes) if possible. The question is simple - have you had this happen and if so, did you find a solution? Does anyone now how to force a not-yet-visible swf to initialize? Thanks guys.

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  • Create a popup window in Mediawiki

    - by Karthick
    I am customising the mediawiki for our internal portal. I need to open a popup window on clicking a link in the wikitext. This popup would take information from the mysql database and display a movie clip or a document or something. Anyone knows how this can be done?

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  • How can this code throw a NullReferenceException?

    - by Davy8
    I must be going out of my mind, because my unit tests are failing because the following code is throwing a null ref exception: int pid = 0; if (parentCategory != null) { Console.WriteLine(parentCategory.Id); pid = parentCategory.Id; } The line that's throwing it is: pid = parentCategory.Id; The console.writeline is just to debug in the NUnit GUI, but that outputs a valid int. Edit: It's single-threaded so it can't be assigned to null from some other thread, and the fact the the Console.WriteLine successfully prints out the value shows that it shouldn't throw. Edit: Relevant snippets of the Category class: public class Category { private readonly int id; public Category(Category parent, int id) { Parent = parent; parent.PerformIfNotNull(() => parent.subcategories.AddIfNew(this)); Name = string.Empty; this.id = id; } public int Id { get { return id; } } } Well if anyone wants to look at the full code, it's on Google Code at http://code.google.com/p/chefbook/source/checkout I think I'm going to try rebooting the computer... I've seen pretty weird things fixed by a reboot. Will update after reboot. Update: Mystery solved. Looks like NUnit shows the error line as the last successfully executed statement... Copy/pasted test into new console app and ran in VS showed that it was the line after the if statement block (not shown) that contained a null ref. Thanks for all the ideas everyone. +1 to everyone that answered.

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  • How do you populate a UIImage view with ASIHTTPRequest given @2x?

    - by Jonathan Page
    I've been trying to load images from a url using ASIHTTPRequest but I always come up with a blank UIImage. I think it might have something to do with iOS automatically choosing the @2x named version of images or vica versa. [ASIHTTPRequest setDefaultCache:[ASIDownloadCache sharedCache]]; NSString *url_string = [NSString stringWithFormat:@"http://173.246.100.185/%@", [eventDictionary objectForKey:kEventDescriptionImageURLKey]]; NSURL *url = [NSURL URLWithString:url_string]; __block ASIHTTPRequest *request = [ASIHTTPRequest requestWithURL:url]; [request setDownloadCache:[ASIDownloadCache sharedCache]]; [request setCachePolicy:ASIAskServerIfModifiedCachePolicy|ASIFallbackToCacheIfLoadFailsCachePolicy]; [request setCacheStoragePolicy:ASICachePermanentlyCacheStoragePolicy]; [request setSecondsToCache:86400]; [request setDelegate:self]; [request setCompletionBlock:^{ NSLog(@"Successful Update"); [self makeAssignment]; }]; [request setFailedBlock:^{ NSError *error = [request error]; NSLog(@"%@", [error localizedDescription]); UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Update Failed" message:[error localizedDescription] delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil]; [alert show]; [alert release]; }]; [request startAsynchronous]; NSLog(@"%@", url_string); The makeAssignment method is below. NSString *url_string = [NSString stringWithFormat:@"http://173.246.100.185/%@", [eventDictionary objectForKey:kEventDescriptionImageURLKey]]; NSURL *url = [NSURL URLWithString:url_string]; downloadedImage = [[UIImage alloc] initWithContentsOfFile:[[ASIDownloadCache sharedCache] pathToCachedResponseDataForURL:url]]; NSLog(@"%@", downloadedImage); NSLog(@"%@", [[ASIDownloadCache sharedCache] pathToCachedResponseDataForURL:url]); Nothing I do, including naming images @2x on the server or providing both versions, gets it to load. Any ideas? Has anyone done this before? When I load them locally (from within the package) I don't have any issues. Thanks!

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  • How do you hook a C++ compiled dll function to a sql database?

    - by Thomas
    I want to do something like: lastName SIMILARTO(lastName, 'Schwarseneger', 2) where lastName is the field in the database, 'Schwarseneger' is the value that lastName field is being compared to and 2 is the maximum number of characters (edit distance) that can differ between the lastName field, and the entered value. I can implement the SIMILARTO function in C++ using the Levenshtein distance (http://en.wikipedia.org/wiki/Levenshtein_distance), but how do hook the function in a dll to a mySQL implementation?

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  • How can I search on a list of values using Solr/Lucene?

    - by Mike
    Given the following query: (field:value1 OR field:value2 OR field:value3 OR ... OR field:value50) Can this be broken down into something less verbose? Basically I have hundreds of category IDs, and I need to search for items under large groups of category IDs (20-50 at a time). In MySQL, I'd just use field IN(value1, value2, value3) rather than (field = value1 OR field = value2 etc...). Is there a simpler way for Solr/Lucene?

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  • Set a specific stylesheet based on session variable in javascript

    - by user2371301
    I have an option for a user to select his/her own theme while logged into the system and this theme is set in a MYSQL Database and called each time the user logs in, this is called by: <?php $_SESSION['SESS_THEME_NAME']; ?> Now, I had this working in a PHP file but I need it to work in Javascript instead unfortunately. And I need some help. I looked at the code using the developers tools on Google Chrome and looks like the above code is not resolving within the javascript file. Which makes sense because you can't access session variables within a javascript file (as I found by searching Google.) The code is basically supposed to set the specific stylesheet based on the value extracted from the MYSQL database. So if the database says Default the script needs to tell the webpage to use the default.css file. And so on and so forth. My attempt at writing this is as follows: var themName="<?php $_SESSION['SESS_THEME_NAME']; ?>"; if (themeName == "Default") { document.write("<link re='stylesheet' type='text/css' href='css/mws-theme.css'>"); }; if (themeName == "Army") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-army.css'>"); }; if (themeName == "Rocky Mountains") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-rocky.css'>"); }; if (themeName == "Chinese Temple") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-chinese.css'>"); }; if (themeName == "Boutique") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-boutique.css'>"); }; if (themeName == "Toxic") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-toxic.css'>"); }; if (themeName == "Aquamarine") { document.write("<link rel='stylesheet' type='text/css' href='css/mws-theme-aquamarine.css'>"); }; Any help once so ever would be awesome and much much appreciated! I am reaching a deadline :/

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  • Setting acquired location to a text view: How to maintain?

    - by Mark
    Hi, I have built an app for the Motorola Droid which should automatically update a server with the phone's location. After the user performs a particular task on the main activity screen, an alarm is set to update the user's location periodically, using a service. The alarm is explicitly stopped when the user completes another task. Thing is, I have set up a location manager within the main activity's onCreate() method which is supposed to place the first acquired lat/long into two textview fields. Even though the manifest is set up for acquiring coarse and fine coords and I'm using requestLocationUpdates (String provider, long minTime, float minDistance, LocationListener listener), with minTime and minDistance set to zero, I'm not seeing the coords coming up on the screen. With that, I'm not recording any locations on the server. When I seed the textviews with sample coords, they are being recorded fine on the server. I am not at a computer that can run the IDE, so don't currently have the code, but am desperate for some help on this. One other thing is that the main activity screen calls a photography app before the user manually clicks "send data". I'm suspicious that I may need to override the main activity's onResume() method to do this location acquisition. Please help, thanks. Mark.

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  • How to check for case sensitive in hibernate criteria

    - by dhiraj
    0 vote down star I have used hibernate to fetch the login information from the mysql database. But the problem is that say for example the user name is 'dhiraj' in the database, now the login is successful by entering the user name, but it is also allowing to enter by taking the user name in uppercase also, e.g., 'DHIRAJ'. I want to restrict it to as it in the database. Can you tell me how to achieve that in hibernate?

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  • SQL Server stored procedure return code oddity

    - by gbn
    Hello The client that calls this code is restricted and can only deal with return codes from stored procs. So, we modified our usual contract to RETURN -1 on error and default to RETURN 0 if no error If the code hits the inner catch block, then the RETURN code default to -4. Where does this come from, does anyone know...? IF OBJECT_ID('dbo.foo') IS NOT NULL DROP TABLE dbo.foo GO CREATE TABLE dbo.foo ( KeyCol char(12) NOT NULL, ValueCol xml NOT NULL, Comment varchar(1000) NULL, CONSTRAINT PK_foo PRIMARY KEY CLUSTERED (KeyCol) ) GO IF OBJECT_ID('dbo.bar') IS NOT NULL DROP PROCEDURE dbo.bar GO CREATE PROCEDURE dbo.bar @Key char(12), @Value xml, @Comment varchar(1000) AS SET NOCOUNT ON DECLARE @StartTranCount tinyint; BEGIN TRY SELECT @StartTranCount = @@TRANCOUNT; IF @StartTranCount = 0 BEGIN TRAN; BEGIN TRY --SELECT @StartTranCount = 'fish' INSERT dbo.foo (KeyCol, ValueCol, Comment) VALUES (@Key, @Value, @Comment); END TRY BEGIN CATCH IF ERROR_NUMBER() = 2627 --PK violation UPDATE dbo.foo SET ValueCol = @Value, Comment = @Comment WHERE KeyCol = @Key; ELSE RAISERROR ('Tits up', 16, 1); END CATCH IF @StartTranCount = 0 COMMIT TRAN; END TRY BEGIN CATCH IF @StartTranCount = 0 AND XACT_STATE() <> 0 ROLLBACK TRAN; RETURN -1 END CATCH --Without this, we'll send -4 if we hit the UPDATE CATCH block above --RETURN 0 GO --Run with RETURN 0 and fish line commented out DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar />', 'testing' SELECT @rtn; SELECT * FROM dbo.foo DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar2 />', 'testing2' --updated OK but we get @rtn = -4 SELECT @rtn; SELECT * FROM dbo.foo --uncomment fish line DECLARE @rtn int EXEC @rtn = dbo.bar 'abcdefghijkl', '<foobar />', 'testing' --Hit outer CATCH, @rtn = -1 as expected SELECT @rtn; SELECT * FROM dbo.foo

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  • GNU GPL - access to data?

    - by Ke
    Hi, I realise that modified versions of the software should be freely available, but what about the content that is held within a mysql database for instance? does that have to be available too? Cheers ke

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  • Copying a foreign Subversion repository to keep under dependencies

    - by Jonathan Sternberg
    I want to keep dependencies for my project in our own repository, that way we have consistent libraries for the entire team to work with. For example, I want our project to use the Boost libraries. I've seen this done in the past with putting dependencies under a "vendor" or "dependencies" folder. But I still want to be able to update these dependencies. If a new feature appears in a library and we need it, I want to just be able to update that repository within our own repository. I don't want to have to recopy it and put it under version control again. I'd also like for us to have the ability to change dependencies if a small change is needed without stopping us from ever updating the library. I want the ability to do something like 'svn cp', then be able to 'svn merge' in the future. I just tried this with the boost trunk, but I'm not able to get any history using 'svn log' on the copy I made. How do I do this? What is usually done for large projects with dependencies?

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  • What is the best Linux distribution as a Xen host?

    - by St3fan
    I ordered a server for the home office and I would like to partition it with Xen. I think this will keep things clean and easier to maintain. I will be running things like MySQL, PostgreSQL, Tomcat and my own code on this machine. My question is: what freely available Linux distribution has the best Xen hosting facilities?

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  • White Screen of Death (WSOD) in Browser

    - by nickyt
    Here's the specs: ASP.NET 3.5 using ASP.NET AJAX AJAX Control Toolkit jQuery 1.3.2 web services IIS6 on Windows Server 2003 SP1 SP1 SQLServer 2005 SP3 Site is SSL Here's the problem: I'm getting the White Screen of Death (WSOD) in pretty much any browser (at least FireFox and IE 7/8). We have an application that uses one popup window for updating records. Most of the time when you click on the [Edit] button to edit a record, the popup window opens and loads the update page. However, after editing records for a while, all of a sudden the popup window will open, but it stays blank and just hangs. The URL is in the address bar. Loading up Fiddler I noticed that the request for the update page is never sent which leads me to believe it's some kind of lockup on the client-side. If I copy the same URL that's in the popup window into a new browser window, the page generally loads fine. Observations: - Since the request is never sent to the server, it's definitely something client-side - Only appears to happen when there is some semblance of traffic on the site which is weird because this appears to be contained within client-side code - There is a web service being called in the background every few seconds checking if the user is logged on, but this doesn't cause the freeze. I'm really at a loss here. I've googled WSOD but not much seems to appear related to my specific WSOD. Any ideas?

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  • Class design when working with dataset

    - by MC
    If you have to retrieve data from a database and bring this dataset to the client, and then allow the user to manipulate the data in various ways before updating the database again, what is a good class design for this if the data tables will not have a 1:1 relationship with the class objects? Here are some I came up with: Just manipulate the DataSet itself on the client and then send it back to the database as is. This will work though obviously the code will be very dirty and not well-structured. Same as #1, but wrap the dataset code around classes. What I mean is that you may have a class that takes a dataset or a datatable in its constructor, and then provides public methods and properties to simplify the code. Inside these methods and properties it will be reading or manipulating the dataset. To update the database afterwards will be easy because you already have the updated dataset. Get rid of the dataset entirely on the client, convert to objects, then convert back to a dataset when needing to update the database. Is there any good resources where I can find information on this?

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  • Why an object declared in method is subject to garbage collection before the method returns?

    - by SiLent SoNG
    Consider an object declared in a method: public void foo() { final Object obj = new Object(); // A long run job that consumes tons of memory and // triggers garbage collection } Will obj be subject to garbage collection before foo() returns? UPDATE: Previously I thought obj is not subject to garbage collection until foo() returns. However, today I find myself wrong. I have spend several hours in fixing a bug and finally found the problem is caused by obj garbage collected! Can anyone explain why this happens? And if I want obj to be pinned how to achieve it? Here is the code that has problem. public class Program { public static void main(String[] args) throws Exception { String connectionString = "jdbc:mysql://<whatever>"; // I find wrap is gc-ed somewhere SqlConnection wrap = new SqlConnection(connectionString); Connection con = wrap.currentConnection(); Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY); stmt.setFetchSize(Integer.MIN_VALUE); ResultSet rs = stmt.executeQuery("select instance_id, doc_id from crawler_archive.documents"); while (rs.next()) { int instanceID = rs.getInt(1); int docID = rs.getInt(2); if (docID % 1000 == 0) { System.out.println(docID); } } rs.close(); //wrap.close(); } } After running the Java program, it will print the following message before it crashes: 161000 161000 ******************************** Finalizer CALLED!! ******************************** ******************************** Close CALLED!! ******************************** 162000 Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: And here is the code of class SqlConnection: class SqlConnection { private final String connectionString; private Connection connection; public SqlConnection(String connectionString) { this.connectionString = connectionString; } public synchronized Connection currentConnection() throws SQLException { if (this.connection == null || this.connection.isClosed()) { this.closeConnection(); this.connection = DriverManager.getConnection(connectionString); } return this.connection; } protected void finalize() throws Throwable { try { System.out.println("********************************"); System.out.println("Finalizer CALLED!!"); System.out.println("********************************"); this.close(); } finally { super.finalize(); } } public void close() { System.out.println("********************************"); System.out.println("Close CALLED!!"); System.out.println("********************************"); this.closeConnection(); } protected void closeConnection() { if (this.connection != null) { try { connection.close(); } catch (Throwable e) { } finally { this.connection = null; } } } }

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  • Sample twitter application

    - by Jack
    I have installed WAMP and running PHP scripts on localhost. I have enabled cURL. Here is my code. <?php function updateTwitter($status) { // Twitter login information $username = 'xxxxx'; $password = 'xxxxx'; // The url of the update function $url = 'http://twitter.com/statuses/update.xml'; // Arguments we are posting to Twitter $postargs = 'status='.urlencode($status); // Will store the response we get from Twitter $responseInfo=array(); // Initialize CURL $ch = curl_init($url); // Tell CURL we are doing a POST curl_setopt($ch, CURLOPT_PROXY,"localhost:80"); curl_setopt ($ch, CURLOPT_POST, true); // Give CURL the arguments in the POST curl_setopt ($ch, CURLOPT_POSTFIELDS, $postargs); // Set the username and password in the CURL call curl_setopt($ch, CURLOPT_USERPWD, $username.':'.$password); // Set some cur flags (not too important) curl_setopt($ch, CURLOPT_VERBOSE, 1); curl_setopt($ch, CURLOPT_NOBODY, 0); curl_setopt($ch, CURLOPT_HEADER, 0); curl_setopt($ch, CURLOPT_FOLLOWLOCATION,1); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); // execute the CURL call $response = curl_exec($ch); if($response === false) { echo 'Curl error: ' . curl_error($ch); } else { echo 'Operation completed without any errors<br/>'; } // Get information about the response $responseInfo=curl_getinfo($ch); // Close the CURL connection curl_close($ch); // Make sure we received a response from Twitter if(intval($responseInfo['http_code'])==200){ // Display the response from Twitter echo $response; }else{ // Something went wrong echo "Error: " . $responseInfo['http_code']; } curl_close($ch); } updateTwitter("Just finished a sweet tutorial on http://brandontreb.com"); ?> Here's my output Operation completed without any errors Error: 404 Here's what error 404 means 404 Not Found: The URI requested is invalid or the resource requested, such as a user, does not exists. Please help.

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  • Opening Ms word/ Excel / PPT AND PDF in Flex

    - by Manan
    Hi , I am looking for a solution preferrably 3rd party component , to open / disply word/excel/ppt and PDF document into flex : Flow is like this : User uploads any of the file .doc/.docx/.pdf/.ppt etc . This file is then displayed in flex area , without having user to get Office . ( Office WEB Component ) is ruled out because it needs office to be installed already . print2flash.com sounds good but their problem is they are on windows , my setup is LAMP PHP / mysql over Linux . Thanks

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  • Flex DataGridColumn with array of objects as data provider

    - by rforte
    I have a datagrid that uses an array of objects as the data provider. The objects are essentially key/value pairs: { foo:"something"} { bar:"hello"} { caca:"lorem"} The datagrid has 2 columns. The first column is the key and the second column is the value. Right now my grid looks like: My dataFormatter function makes sure that depending on the column (i.e. the dataField value) the correct key or value gets printed out. This works fine for displaying. However, as soon as I try and edit the value field it essentially adds a new value into the object with a key of '1'. For example, if I edit the {caca:"lorem"} object it will then contain the value {caca:"lorem",1:"new value"}. Is there any possible way I can set the DataGridColumn so that when I edit a value it will update the value associated with the key rather than inserting a new value? I've tried using a custom item editor but it still does the insert. It seems like I need to be able to update the 'dataField' with the actual key value but I'm not sure how to do that.

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  • Hibernate and default values

    - by Schildmeijer
    Is it possible to use annotations to map a default value for a column? eg. I have a column named 'date' which is supposed to be '0000-00-00 00:00:00' if not date is explicitly given. I know I can add this to the ctor of the Entity. But then the default behavior will no be present in my database backend. (eg. Default column in mysql)

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  • updating multiple nodes in xml with xquery and xdmp:node-replace

    - by morja
    Hi all, I wnat to update an XML document in my xml database (Marklogic). I have xml as input and want to replace each node that exists in the target xml. If a node does not exist it would be great if it gets added, but thats maybe another task. My XML in the database: <user> <username>username</username> <firstname>firstname</firstname> <lastname>lastname</lastname> <email>[email protected]</email> <comment>comment</comment> </user> The value of $user_xml: <user> <firstname>new firstname</firstname> <lastname>new lastname</lastname> </user> My function so far: declare function update-user ( $username as xs:string, $user_xml as node()) as empty-sequence() { let $uri := user-uri($username) return for $node in $user_xml/user return xdmp:node-replace(fn:doc($uri)/user/fn:node-name($node), $node) }; First of all I cannot iterate over $user_xml/user. If I try to iterate over $user_xml I get "arg1 is not of type node()" exception. But maybe its the wrong approach anyway? Does anybody maybe have sample code how to do this?

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  • Need some information regarding data warehousing field

    - by Mirage
    I am a web developer and i would like to shift my field to data warehousing. Can anyone please give me some idea , which langauges or stuff i need to learn like cogonos , datastage, etl or IF anyone currently working can guide me how can i start , i will thankful to you. DO i nned to do oracle because i know mysql , sql. My basic understanding with databse is good. Any books

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  • Store CSPC and UPC Codes in Rails

    - by Kevin Sylvestre
    What the best way to store CSPC and UPC codes are in Rails? I used integers with SQLite, but had overflow issues when moving to production. I've since switch to strings, but am not sure if a better generic datatype (needs to support SQLite, MySQL and PostgreSQL). Thanks.

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  • Visual studio erroneous errors when building a website?

    - by Curtis White
    Visual Studio 2008 shows a lot of erroneous errors when building a website (not a web project) in the errors list. These errors are usually corrected (removed) when I rebuild the site a couple times but they cost me wasted time. Is there anyway to hide the erroneous errors? Update: I've decided to look into this to see if I could reproduce it. This is the exact behavior I am seeing, using the website model, I type some invalid syntax on a page. The errors list fills up with errors. I correct the error and the errors list does not update. I build the project and the errors list still shows the errors but the build shows as build completed. I build the project a second time and the errors list is cleared. My question is there anyway to make the errors list clear on the first build? I thought it might have something to do with page build vs website build but it seems to make no difference. I am not using any third party dlls on this website.

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  • Help me write my LISP :) LISP environments, Ruby Hashes...

    - by MikeC8
    I'm implementing a rudimentary version of LISP in Ruby just in order to familiarize myself with some concepts. I'm basing my implementation off of Peter Norvig's Lispy (http://norvig.com/lispy.html). There's something I'm missing here though, and I'd appreciate some help... He subclasses Python's dict as follows: class Env(dict): "An environment: a dict of {'var':val} pairs, with an outer Env." def __init__(self, parms=(), args=(), outer=None): self.update(zip(parms,args)) self.outer = outer def find(self, var): "Find the innermost Env where var appears." return self if var in self else self.outer.find(var) He then goes on to explain why he does this rather than just using a dict. However, for some reason, his explanation keeps passing in through my eyes and out through the back of my head. Why not use a dict, and then inside the eval function, when a new "sub-environment" needs to be created, just take the existing dict and update the key/value pairs that need to be updated, and pass that new dict into the next eval? Won't the Python interpreter keep track of the previous "outer" envs? And won't the nature of the recursion ensure that the values are pulled out from "inner" to "outer"? I'm using Ruby, and I tried to implement things this way. Something's not working though, and it might be because of this, or perhaps not. Here's my eval function, env being a regular Hash: def eval(x, env = $global_env) ........ elsif x[0] == "lambda" then ->(*args) { eval(x[2], env.merge(Hash[*x[1].zip(args).flatten(1)])) } ........ end The line that matters of course is the "lambda" one. If there is a difference, what's importantly different between what I'm doing here and what Norvig did with his Env class? If there's no difference, then perhaps someone can enlighten me as to why Norvig uses the Env class. Thanks :)

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