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  • getting active records to display as a plist

    - by phil swenson
    I'm trying to get a list of active record results to display as a plist for being consumed by the iphone. I'm using the plist gem v 3.0. My model is called Post. And I want Post.all (or any array or Posts) to display correctly as a Plist. I have it working fine for one Post instance: [http://pastie.org/580902][1] that is correct, what I would expect. To get that behavior I had to do this: class Post < ActiveRecord::Base def to_plist attributes.to_plist end end However, when I do a Post.all, I can't get it to display what I want. Here is what happens: http://pastie.org/580909 I get marshalling. I want output more like this: [http://pastie.org/580914][2] I suppose I could just iterate the result set and append the plist strings. But seems ugly, I'm sure there is a more elegant way to do this. I am rusty on Ruby right now, so the elegant way isn't obvious to me. Seems like I should be able to override ActiveRecord and make result-sets that pull back more than one record take the ActiveRecord::Base to_plist and make another to_plist implementation. In rails, this would go in environment.rb, right?

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  • Trigger alert when database entries are added, not when they are removed

    - by Jeremy
    I have a jQuery script running that makes a periodic AJAX call using the following code. var a = moment(); var dayOfMonth = a.format("MMM Do"); var timeSubmitted = a.format("h:mm a"); var count_cases = -1; var count_claimed = -1; setInterval(function(){ //check if new lead was added to the db $.ajax({ type : "POST", url : "inc/new_lead_alerts_process.php", dataType: 'json', cache: false, success : function(response){ $.getJSON("inc/new_lead_alerts_process.php", function(data) { if (count_cases != -1 && count_cases != data.count) { window.location = "new_lead_alerts.php?id="+data.id; } count_cases = data.count; }); } }); This is the PHP that runs with each call: $count = mysql_fetch_array(mysql_query("SELECT count(*) as count FROM leads")); $client_id = mysql_fetch_array(mysql_query("SELECT id, client_id FROM leads ORDER BY id DESC LIMIT 1")); echo json_encode(array("count" => $count['count'], "id" => $client_id['id'], "client_id" => $client_id['client_id'])); I need to change the code so that the alert only triggers when a new entry is added to the database, not when an existing entry is removed. As it stands, the alert fires on both events. Any help is greatly appreciated.

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  • Quick question regarding MVC framework for a java game

    - by Jason
    I have a question regarding the use of the MVC framework for a blackjack game im writing in java. As I understand, my model would be a class that stores the state of the game, and more specifically, each players hand. Within the model class, I would have an array of listeners, which would be notified each time the game state changes (ie a player has drawn a new card). These listeners would be my viewer, which is the class that handles the display of the game. This class would implement the ActionListener interface, and each time the model changes, it would call/"notify" my viewer's actionPerformed method. My question is as follows: I intend to have two JPanels, each devoted to displaying the respective player's hand. As a player draws a new card, a new ImageIcon would be added to the panel. My question is how would the viewer class know what card has been added to the player's hand? I suppose I could store the player's hand before a notify event, and then upon the notification event, compare the new state with the old, to find out what has changed. I'm a complete novice here, so I could be completely wrong, but it seems a bit tedious to do this. Is there a more efficient/common way of detecting what has changed in the model between the before and after state? Another solution would be to redraw the entire panel each time the notification occurs? Would this be a better idea?

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  • Big-Oh running time of code in Java (are my answers accurate

    - by Terry Frederick
    the Method hasTwoTrueValues returns true if at least two values in an array of booleans are true. Provide the Big-Oh running time for all three implementations proposed. // Version 1 public boolean has TwoTrueValues( boolean [ ] arr ) { int count = 0; for( int i = 0; i < arr. length; i++ ) if( arr[ i ] ) count++; return count >= 2; } // Version 2 public boolean hasTwoTrueValues( boolean [ ] arr ) { for( int i = 0; i < arr.length; i++ ) for( int j = i + 1; j < arr.length; j++ ) if( arr[ i ] && arr[ j ] ) return true; } // Version 3 public boolean hasTwoTrueValues( boolean [ ] arr ) { for( int i = 0; i < arr.length; i++ if( arr[ i ] ) for( int j = i + 1; j < arr.length; j++ ) if( arr[ j ] ) return true; return false; } For Version 1 I say the running time is O(n) Version 2 I say O(n^2) Version 3 I say O(n^2) I am really new to this Big Oh Notation so if my answers are incorrect could you please explain and help.

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  • Is fetching data from database a get-method thing?

    - by theva
    I have a small class that I call Viewer. This class is supposed to view the proper layout of each page or something like that... I have a method called getFirstPage, when called the user of this method will get a setting value for which page is currently set as the first page. I have some code here, I think it works but I am not really shure that I have done it the right way: class Viewer { private $db; private $user; private $firstPage; function __construct($db, $user) { $this->db = $db; if(isset($user)) { $this->user = $user; } else { $this->user = 'default'; } } function getFistPage() { $std = $db->prepare("SELECT firstPage FROM settings WHERE user = ':user'"); $std->execute(array(':user' => $user)); $result = $std->fetch(); $this->firstPage = $result['firstPage']; return $this->firstPage; } } My get method is fetching the setting from databse (so far so good?). The problem is that then I have to use this get method to set the private variable firstPage. It seems like I should have a set method to do this, but I cannot really have a set method that just fetch some setting from database, right? Because the user of this object should be able to assume that there already is a setting defined in the object... How should I do that?

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  • num_rows is 0 when it should be >0 for php mysqli code

    - by jpporterVA
    My num_rows is coming back as 0, and I've tried calling it several ways, but I'm stuck. Here is my code: $conn = new mysqli($dbserver, "dbuser", "dbpass", $dbname); // get the data $sql = 'SELECT AT.activityName, AT.createdOn FROM userActivity UA, users U, activityType AT WHERE U.userId = UA.userId and AT.activityType = UA.activityType and U.username = ? order by AT.createdOn'; $stmt = $conn->stmt_init(); $stmt->prepare($sql); $stmt->bind_param('s', $requestedUsername); $stmt->bind_result($activityName, $createdOn); $stmt->execute(); // display the data $numrows = $stmt->num_rows; $result=array("user activity report for: " . $requestedUsername . " with " . $numrows . " rows:"); $result[]="Created On --- Activity Name"; while ($stmt->fetch()) { $msg = " " . $createdOn . " --- " . $activityName . " "; $result[] = $msg; } $stmt->close(); There are multiple rows found, and the fetch loop process them just fine. Any suggestions on what will enable me to get the number of rows returned in the query? Suggestions are much appreciated. Thanks in advance.

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  • Are there concurrency problems when using -performSelector:withObject:afterDelay: ?

    - by mystify
    For example, I often use this: [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:someDelay]; Now, lets say I call this 10 times to perform at the exact same delay, like: [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; - (void)doSomethingAfterDelay:(id)someObject { /* access an array, read stuff, write stuff, do different things that would suffer in multithreaded environments .... all operations are nonatomic! */ } I have observed pretty strange behavior when doing things like this. For my understanding, this method schedules a timer to fire on the current thread, so in this case the main thread. But since it doesn't create new threads, it actually should not be possible to run into concurrency problems, right?

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  • Are there concurrency problems when using -performSelector:withObject:afterDelay: ?

    - by mystify
    For example, I often use this: [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:someDelay]; Now, lets say I call this 10 times to perform at the exact same delay, like: [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; [self performSelector:@selector(doSomethingAfterDelay:) withObject:someObject afterDelay:2.0]; - (void)doSomethingAfterDelay:(id)someObject { /* access an array, read stuff, write stuff, do different things that would suffer in multithreaded environments .... all operations are nonatomic! */ } I have observed pretty strange behavior when doing things like this. For my understanding, this method schedules a timer to fire on the current thread, so in this case the main thread. But since it doesn't create new threads, it actually should not be possible to run into concurrency problems, right?

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  • "Add another item" form functionality

    - by GSTAR
    I have a form that lets a user enter their career history - it's a very simple form with only 3 fields - type (dropdown), details (textfield) and year (dropdown). Basically I want to include some dynamic functionality whereby the user can enter multiple items on the same page and then submit them all in one go. I had a search on Google and found some examples but they were all based on tables - my markup is based on DIV tags: <div class="form-fields"> <div class="row"> <label for="type">Type</label> <select id="type" name="type"> <option value="Work">Work</option> </select> </div> <div class="row"> <label for="details">Details</label> <input id="details" type="text" name="details" /> </div> <div class="row"> <label for="year">Year</label> <select id="year" name="year"> <option value="2010">2010</option> </select> </div> </div> So basically the 3 DIV tags with class "row" need to be duplicated, or to simplify things - the div "form-fields" could just be duplicated. I am also aware that the input names would have to converted to array format. Additionally each item will require a "remove" button. There will be a main submit button at the bottom which submits all the data. Anyone got an elegant solution for this?

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  • Creating a Variable From Two Others

    - by John
    Hello, In the HTML table below, I would like to add a third column that equals $row["countSubmissions"] times 10 plus $row["countComments"]. How could I do this? Thanks in advance, John $sqlStr = "SELECT l.loginid, l.username, COALESCE(s.total, 0) AS countSubmissions, COALESCE(c.total, 0) AS countComments FROM login l LEFT JOIN ( SELECT loginid, COUNT(1) AS total FROM submission GROUP BY loginid ) s ON l.loginid = s.loginid LEFT JOIN ( SELECT loginid, COUNT(1) AS total FROM comment GROUP BY loginid ) c ON l.loginid = c.loginid GROUP BY l.loginid ORDER BY countSubmissions DESC LIMIT 10"; $result = mysql_query($sqlStr); $arr = array(); echo "<table class=\"samplesrec1edit\">"; while ($row = mysql_fetch_array($result)) { echo '<tr>'; echo '<td class="sitename1edit1"><a href="http://www...com/.../members/index.php?profile='.$row["username"].'">'.stripslashes($row["username"]).'</a></td>'; echo '<td class="sitename1edit2">'.stripslashes($row["countSubmissions"]).'</td>'; echo '<td class="sitename1edit2">'.stripslashes($row["countComments"]).'</td>'; echo '</tr>'; } echo "</table>";

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  • SetMatrix() does not copy all values to HLSL

    - by Tili
    Hi, I want to use the contents of a vector of D3DXMatrices to my shader. m_pLightMatrices->SetMatrixArray(&currentLightMatrices[0].m[0][0],0,numLights); As we know the internals of a vector this poses no problems (as it is just a dynamic array). Now when I access this matrix in hlsl to fill up a struct I get this strange behavior: struct LightTest { float3 LightPos; float LightRange; float4 LightDiffuse; float3 LightAtt; }; float4x4 currentLight = gLights[0]; LightTest lt; lt.LightPos = currentLight._m00_m01_m02; //{0,0,0} lt.LightDiffuse = currentLight[1].rgba; //{0,0,0,0} lt.LightRange = currentLight._m03; //this gives me a value lt.LightAtt = currentLight[2].xyz; //{0,0,0} While debugging I see that my matrix is nicely filled with the variables I want. When I try to hardcode check what is in the struct I get all zero's, except the LightRange. As you can see I tried different methods of accessing the float4x4 but without any other results. Why oh why is hlsl not copying all my variables ?

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  • how to fetch data using jquery

    - by user3566029
    I have tried to connect my index.php file in 000webhost.com using jQuery. From the site menu I have connected with 000webhost using FTP details available in 000webhost.com. When I tried to read data from jQuery it doesn’t working. Anyone please tell me what should I need to change? Should I need to connect my Dreamweaver database to webhost? If yes please explain? This is what I have done. index.php $mysql_host = "mysql0.000webhost.com"; $mysql_database = "a000000_mydb"; $mysql_user = "a000000_root"; $mysql_password = "******"; $conn=@mysql_connect ( $mysql_host,$mysql_user,$mysql_password )or die('aa'); mysql_select_db($mysql_database,$conn) or die('eoor on db'); $quer=mysql_query("SELECT * FROM sam"); $res=array(); while($row=mysql_fetch_row($quer)) { $res[]=$row; } print(json_encode($res)); return json_encode($res); mysql_close(); index.html $.get('public_html/index.php', function( data ) { alert( 'Successful' +data); });

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  • RESTful API: How to model JSON representation?

    - by Jan P.
    I am designing a RESTful API for a booking application. You can request a list of accommodations. And that's where I don't really know how to design the JSON represenation. This is my XML representation: <?xml version="1.0" encoding="utf-8"?> <accommodations> <accommodation> <name>...</name> <category>couch</category> </accommodation> <accommodation> <name>...</name> <category>room</category> </accommodation> <accommodations> My first try to convert this to JSON resulted in this output (1): { "0": { "name": "...", "category": "couch" }, "1": { "name": "...", "category": "room" } } But as I looked how others APIs did it, I found something looking more like this (2): [ { "name": "...", "category": "couch" }, { "name": "...", "category": "room" } ] I know version 1 is an object, and version 2 an array. But which one is better in this case?

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  • Extending the CI_DB_active_record class in codeigniter 2.0

    - by ctrane
    I am writing my first program with Codeigniter, and have run into a problem. I will start with a focused description of the problem and can broaden it if I need to: I need to write a multi-dimensional array to the DB and want to use the insert_batch function from the CI_DB_active_record class to do so. The problem is that I need to write empty values as NULL for some fields while other fields need to be empty strings. The current function wraps all values with single quotes, and I cannot find a way to write null values to the database for specified fields. I would also like to increase the number of records per batch. I see how to extend models, libraries, etc., but is there a way to extend the CI_DB_active_record class without modifying core classes? The minimal amount of core class modification to make this work that I have found is modifying the following lines in the DB.php file (changing the require_once file to the new file that extends the CI_DB_active_record class and changing the CI_DB_active_record class name to the new class name): require_once(BASEPATH.'database/DB_active_rec'.EXT); if ( ! class_exists('CI_DB')) { eval('class CI_DB extends CI_DB_active_record { }'); } Can I do better?

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  • How to get a specific attribute from an object list?

    - by anarhikos
    I've an array keeping a list of Group objects. I want to set this list to the DropDownChoice component. However I want to show the end user only the name attribute of Group objects, and then get the selected values' id attribute to add database. What to do? private List<Group> groupTypes; DatabaseApp db = new DatabaseApp(); groupTypes = db.getGroups(); groupDropDownChoice = new DropDownChoice("type", groupTypes); ... ... addUserForm.add(new Button("submit"){ @Override public void onSubmit(){ Group group = (Group) groupDropDownChoice.getModelObject(); ... ... db.addUser(group.getId(), den, name, login, email, password1); DatabaseApp.java public List<Group> getGroups() throws SQLException{ List<Group> groups = new ArrayList<Group>(); try { String query = "SELECT * FROM [GROUP]"; Statement statement = db.createStatement(); ResultSet result = statement.executeQuery(query); while(result.next()){ int id = result.getInt("ID"); String name = result.getString("NAME"); groups.add(new Group(id, name)); } result.close(); } catch (SQLException ex) { throw new SQLException(ex.getMessage()); } return groups; }

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  • Parsing html output and executing javascript

    - by user1841964
    I have this function: function parseScript(_source) { var source = _source; var scripts = new Array(); while(source.indexOf("<script") > -1 || source.indexOf("</script") > -1) { var s = source.indexOf("<script"); var s_e = source.indexOf(">", s); var e = source.indexOf("</script", s); var e_e = source.indexOf(">", e); scripts.push(source.substring(s_e+1, e)); source = source.substring(0, s) + source.substring(e_e+1); } for(var i=0; i<scripts.length; i++) { try { eval(scripts[i]); } catch(ex) { } } return source; } It parses and execute Javascript wonderfully except the when in <script type='text/javascript' src='scripts/gen_validatorv31.js'></script> the src file never gets executed.

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  • MySQL/PHP Search Efficiency

    - by iMaster
    Hi! I'm trying to create a small search for my site. I've tried using full-text index search, but I could never get it to work. Here is what I've come up with: if(isset($_GET['search'])) { $search = str_replace('-', ' ', $_GET['search']); $result = array(); $titles = mysql_query("SELECT title FROM Entries WHERE title LIKE '%$search%'"); while($row = mysql_fetch_assoc($titles)) { $result[] = $row['title']; } $tags = mysql_query("SELECT title FROM Entries WHERE tags LIKE '%$search%'"); while($row = mysql_fetch_assoc($tags)) { $result[] = $row['title']; } $text = mysql_query("SELECT title FROM Entries WHERE entry LIKE '%$search%'"); while($row = mysql_fetch_assoc($text)) { $result[] = $row['title']; } $result = array_unique($result); } So basically, it searches through all the titles, body-text, and tags of all the entries in the DB. This works decently well, but I'm just wondering how efficient would it be? This would only be for a small blog, too. Either way I'm just wondering if this could be made any more efficient.

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  • How to check of which user-defined type a current JSON element is during $.each()?

    - by Bob
    I have the following structure for a JSON file: ({condos:[{Address:'123 Fake St.', Lat:'56.645654', Lng:'23.534546'},{... another condo ...},{...}],houses:[{Address:'1 Main Ave.', Lat:'34.765766', Lng:'27.8786674'},{... another house ...}, {...}]}) So, I have a list of condos and houses in one big JSON array. I want to plot them all on my map, but I want to give condos and houses different marker icons( blue marker for condos, green marker for houses ). Problem I have is - figuring out how to distinguish between types of markers when I $.each() through them. How would I use if to check whether I'm working with a condo or a house at the moment? var markers = null; $('#map').gmap(mapOptions).bind('init', function(){ $.post('getMarkers.php', function(json){ markers = json; $.each(markers, function(type, dataMembers) { $.each(dataMembers, function(i, j){ //if house use house.png to create marker $('#map').gmap('addMarker', { 'position': new google.maps.LatLng(parseFloat(Lat), parseFloat(Lng)), 'bounds':true, 'icon':'house.png' } ); //if condo use condo.png $('#map').gmap('addMarker', { 'position': new google.maps.LatLng(parseFloat(Lat), parseFloat(Lng)), 'bounds':true, 'icon':'condo.png' } ); }); }); }); });

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  • Integration testing - can it be done right?

    - by Max
    I used TDD as a development style on some projects in the past two years, but I always get stuck on the same point: how can I test the integration of the various parts of my program? What I am currently doing is writing a testcase per class (this is my rule of thumb: a "unit" is a class, and each class has one or more testcases). I try to resolve dependencies by using mocks and stubs and this works really well as each class can be tested independently. After some coding, all important classes are tested. I then "wire" them together using an IoC container. And here I am stuck: How to test if the wiring was successfull and the objects interact the way I want? An example: Think of a web application. There is a controller class which takes an array of ids, uses a repository to fetch the records based on these ids and then iterates over the records and writes them as a string to an outfile. To make it simple, there would be three classes: Controller, Repository, OutfileWriter. Each of them is tested in isolation. What I would do in order to test the "real" application: making the http request (either manually or automated) with some ids from the database and then look in the filesystem if the file was written. Of course this process could be automated, but still: doesn´t that duplicate the test-logic? Is this what is called an "integration test"? In a book i recently read about Unit Testing it seemed to me that integration testing was more of an anti-pattern?

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  • can't upload greater 50MB

    - by Syom
    i want to upload two files. here is the script <? ini_set('memory_limit', "400M"); ini_set('file_uploads', "5"); ini_set('max_execution_time', "900"); ini_set('upload_max_filesize', "400M"); ini_set('post_max_size', "400M"); ?> <form action="form.php" method="post" enctype="multipart/form-data" /> <input type="file" name="video" /> <input type="file" name="picture" > <input type="submit" class="input" value="?????" /> </form> form.php: <? ini_set('memory_limit', "400M"); ini_set('file_uploads', "5"); ini_set('max_execution_time', "900"); ini_set('upload_max_filesize', "400M"); ini_set('post_max_size', "400M"); print_r($_FILES); //returns Array ( ) ?> i've asked about this question here , and i've set ini_set(...) as you see, but when i try to upload the file greater than 50MB, it doesn't happen. could you tell me why?

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  • Comparing lists of field-hashes with equivalent AR-objects.

    - by Tim Snowhite
    I have a list of hashes, as such: incoming_links = [ {:title => 'blah1', :url => "http://blah.com/post/1"}, {:title => 'blah2', :url => "http://blah.com/post/2"}, {:title => 'blah3', :url => "http://blah.com/post/3"}] And an ActiveRecord model which has fields in the database with some matching rows, say: Link.all => [<Link#2 @title='blah2' @url='...post/2'>, <Link#3 @title='blah3' @url='...post/3'>, <Link#4 @title='blah4' @url='...post/4'>] I'd like to do set operations on Link.all with incoming_links so that I can figure out that <Link#4 ...> is not in the set of incoming_links, and {:title => 'blah1', :url =>'http://blah.com/post/1'} is not in the Link.all set, like so: #pseudocode #incoming_links = as above links = Link.all expired_links = links - incoming_links missing_links = incoming_links - links expired_links.destroy missing_links.each{|link| Link.create(link)} One route I've tried: I'd rather not rewrite Array#- and such, and I'm okay with converting incoming_links to a set of unsaved Link objects; so I've tried overwriting hash eql? and so on in Link so that it ignored the id equality that AR::Base provides by default. But this is the only place this sort of equality should be considered in the application - in other places the Link#id default identity is required. Is there some way I could subclass Link and apply the hash, eql?, etc overwriting there? The other route I've tried is to pull out the attributes hash for each Link and doing a .slice('id',...etc) to prune the hashes down. But this requires writing seperate methods for keeping track of the Link objects while doing set operations on the hashes, or writing seperate Collection classes to wrap the incoming_links hash-list and Link-list which seems a bit overkill. What is the best way to design this interaction? Extra credit for cleanliness.

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  • [Rails] Accessing error_messages on form_tag

    - by aaronrussell
    I have built a custom form for creating a joining model on a has_many :through relationship. The models look roughly like this: class Team has_many :team_members has_many :members, :through => :team_members end class Member has_many :team_members has_many :teams, :through => :team_members end class TeamMember belongs_to :team belongs_to :member # and this model has some validations too end The form I have built is for selecting which members should be in a team. I won't paste the form, but it uses the form_tag method and basically sends an array of hashes which contain a member_id and a squad_number. I then update the database with an action that looks roughly like this (simplified a bit, but you get the jist): @team.transaction do @team.team_members = params[:team_members].collect{|tm| @team.team_members.new(tm)} if @team.save redirect_to ... else render :action => :members end end Everything works great but I am validating the squad_number for uniqueness and numerically. So, when any of those validations fail, how do I get access to them in my view, and how do I ascertain which of the many members it has failed on?

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  • Value types of variable size

    - by YellPika
    I'm trying to code a small math library in C#. I wanted to create a generic vector structure where the user could define the element type (int, long, float, double, etc.) and dimensions. My first attempt was something like this... public struct Vector<T> { public readonly int Dimensions; public readonly T[] Elements; // etc... } Unfortunately, Elements, being an array, is also a reference type. Thus, doing this, Vector<int> a = ...; Vector<int> b = a; a[0] = 1; b[0] = 2; would result in both a[0] and b[0] equaling 2. My second attempt was to define an interface IVector<T>, and then use Reflection.Emit to automatically generate the appropriate type at runtime. The resulting classes would look roughly like this: public struct Int32Vector3 : IVector<T> { public int Element0; public int Element1; public int Element2; public int Dimensions { get { return 3; } } // etc... } This seemed fine until I found out that interfaces seem to act like references to the underlying object. If I passed an IVector to a function, and changes to the elements in the function would be reflected in the original vector. What I think is my problem here is that I need to be able to create classes that have a user specified number of fields. I can't use arrays, and I can't use inheritance. Does anyone have a solution? EDIT: This library is going to be used in performance critical situations, so reference types are not an option.

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  • Trouble defining method for Javascript class definition.

    - by btoverdrive
    I'm somewhat new to object oriented programming in Javascript and I'm trying to build a handler object and library for a list of items I get back from an API call. Ideally, I'd like the library functions to be members of the handler class. I'm having trouble getting my class method to work however. I defined as part of the class bcObject the method getModifiedDateTime, but when I try to echo the result of the objects call to this method, I get this error: Error on line 44 position 26: Expected ';' this.getModifiedDateTime: function(epochtime) { which leads me to believe that I simply have a syntax issue with my method definition but I can't figure out where. response( { "items": [ {"id":711,"name":"Shuttle","lastModifiedDate":"1268426336727"}, {"id":754,"name":"Formula1","lastModifiedDate":"1270121717721"} ], "extraListItemsAttr1":"blah", "extraListItemsAttr2":"blah2" }); function response(MyObject) { bcObject = new bcObject(MyObject); thing = bcObject.getModifiedDateTime(bcObject.videoItem[0].lastModifiedDate); SOSE.Echo(thing); } function bcObject(listObject) { // define class members this.responseList = {}; this.videoCount = 0; this.videoItem = []; this.responseListError = ""; // instantiate members this.responseList = listObject; this.videoCount = listObject.items.length; // populate videoItem array for (i=0;i<this.videoCount;i++) { this.videoItem[i] = listObject.items[i]; } this.getModifiedDateTime: function(epochtime) { var dateStringOutput = ""; var myDate = new Date(epochtime); dateStringOutput = myDate.toLocaleString(); return dateStringOutput; }; }

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  • Cakephp 2.2 Blog Tutorial undefined constant errors

    - by user1741925
    Have copy pasted the code from Blog tutorial in cakephp 2.2 but its not working. Getting the following errors. Notice (8): Use of undefined constant Html Notice (8): Use of undefined constant Form Notice (8): Use of undefined constant posts Notice (8): Use of undefined constant all Notice (8): Undefined index: all Below is the code for PostsController and index.ctp. <?php class PostsController extends AppController { public $helpers = array(’Html’, ’Form’); public function index() { $this->set(’posts’, $this->Post->find(’all’)); } public function view($id = null) { $this->Post->id = $id; $this->set(’post’, $this->Post->read()); } } ?> index.ctp <h1>Blog posts</h1> <table> <tr> <th>Id</th> <th>Title</th> <th>Created</th> </tr> <?php foreach ($posts as $post): ?> <tr> <td><?php echo $post[’Post’][’id’]; ?></td> <td> <?php echo $post[’Post’][’title’]; ?> </td> <td><?php echo $post[’Post’][’created’]; ?></td> </tr> <?php endforeach; ?> <?php unset($post); ?> </table>

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