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  • C# DDD Populate Immutable Objects

    - by Russel
    Hi I have a immutable Customer class in my domain assembly. It contains the following GET properties : id, firstname and lastname. I have a CustomerRepository class in my persistence assembly. In turn, this CustomerRepository class should populate and return a Customer object using a remote web-serivce. My Customer class contains no setter properties and it contains a private constructor. The reason - I dont want the UI developer to get the wrong idea - He should not be able to create or change a Customer object. My question: How do I get my CustomerRepository to populate my Customer object. Reflection? Or should I sacrifice my design and enable a public constructor for constructing the customer object?

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  • Who needs singletons?

    - by sexyprout
    Imagine you access your MySQL database via PDO. You got some functions, and in these functions, you need to access the database. The first thing I thought of is global, like: $db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'root', 'pwd'); function some_function() { global $db; $db->query('...'); } But it's considered as a bad practice. So, after a little search, I ended up with the Singleton pattern, which "applies to situations in which there needs to be a single instance of a class." According to the example of the manual, we should do this: class Database { private static $instance, $db; private function __construct(){} static function singleton() { if(!isset(self::$instance)) self::$instance = new __CLASS__; return self:$instance; } function get() { if(!isset(self::$db)) self::$db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'user', 'pwd') return self::$db; } } function some_function() { $db = Database::singleton(); $db->get()->query('...'); } some_function(); But I just can't understand why you need that big class when you can do it merely with: class Database { private static $db; private function __construct(){} static function get() { if(!isset(self::$rand)) self::$db = new PDO('mysql:host=127.0.0.1;dbname=toto', 'user', 'pwd'); return self::$db; } } function some_function() { Database::get()->query('...'); } some_function(); This last one works perfectly and I don't need to worry about $db anymore. But maybe I'm forgetting something. So, who's wrong, who's right?

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  • Issue selenium code maintenance

    - by Rajasankar
    I want to group the common methods in one file and use it. For example, login to a page using selenium may be used in multiple times. Define that in class A and call it in class B. However, it throws null pointer exception. class A has public void test_Login() throws Exception { try{ selenium.setTimeout("60000"); selenium.open("http://localhost"); selenium.windowFocus(); selenium.windowMaximize(); selenium.windowFocus(); selenium.type("userName", "admin"); selenium.type("password", "admin"); Result=selenium.isElementPresent("//input[@type='image']"); selenium.click("//input[@type='image']"); selenium.waitForPageToLoad(Timeout); } catch(Exception ex) { System.out.println(ex); ex.printStackTrace(); } } with all other java syntax in class B public void test_kk() throws Exception { try { a.test_Login(); } catch(Exception ex) { System.out.println(ex); ex.printStackTrace(); } } with all syntax. When I execute class B, I got this error, java.lang.NullPointerException at A.test_Login(A.java:32) at B.test_kk(savefile.java:58) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at junit.framework.TestCase.runTest(TestCase.java:168) at junit.framework.TestCase.runBare(TestCase.java:134) at com.thoughtworks.selenium.SeleneseTestCase.runBare(SeleneseTestCase.j ava:212) at junit.framework.TestResult$1.protect(TestResult.java:110) at junit.framework.TestResult.runProtected(TestResult.java:128) at junit.framework.TestResult.run(TestResult.java:113) at junit.framework.TestCase.run(TestCase.java:124) at junit.framework.TestSuite.runTest(TestSuite.java:232) at junit.framework.TestSuite.run(TestSuite.java:227) at junit.textui.TestRunner.doRun(TestRunner.java:116) at junit.textui.TestRunner.doRun(TestRunner.java:109) at junit.textui.TestRunner.run(TestRunner.java:77) at B.main(B.java:77) I hope someone must have tried this before. I may miss something here.

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  • java reflection

    - by user622222
    Hi all, System.out.println("Class name : "); BufferedReader reader= new BufferedReader(new InputStreamReader(System.in)); String line = reader.readLine(); Class<?> writeoutClass = Class.forName(line); Method Writeout = null; for (Method mth : writeoutClass.getDeclaredMethods()) { if (mth.getName().startsWith("Writeout")) { Writeout = mth; break; } It's giving error like that; java.lang.ClassNotFoundException: a How can i generate that class?

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  • ruby subclass filter

    - by Nik
    Hey! Maybe I am getting the idea of a subclass wrong, but I have a Person model and it has an attrib called "age" so Person.first.age #=> '20' Now I want to have a model that's basically persons 55 or older so I know I can have a class like this: class Senior < Person end But how can I "pre-filter" the Senior class so that every object belonging to that class has age = 55? Senior.first.age #=> 56 Thanks!

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  • onMouseOver, hyperlink and rel...help me :(

    - by bahamut100
    Hi, Currently, I have a carrousel on javascript which works when we click on hyperlink, like this : <div id="direction1"> <p> <a href="javascript:" class="carousel-control" rel="next"><img class="fleche_suiv" src="/project/images/next.png" alt="Suivant" title="Suivant" /> </a> </p> </div> I would like execute this evenment with a onMouseOver too. So I try this, but it doesn't work : <div id="direction1"> <p onMouseOver="this.getElementsByTagName('a').click()"> <a href="javascript:" class="carousel-control" rel="next"><img class="fleche_suiv" src="/project/images/next.png" alt="Suivant" title="Suivant" /> </a> </p> </div> How to fix it ???

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  • Scala :: operator, how it works?

    - by Felix
    Hello Guys, in Scala, I can make a caseclass case class Foo(x:Int) and then put it in a list like so: List(Foo(42)) Now, nothing strange here. The following is strange to me. The operator :: is a function on a list, right? With any function with 1 argument in Scala, I can call it with infix notation. An example is 1 + 2 is a function (+) on the object Int. The class Foo I just defined does not have the :: operator, so how is the following possible: Foo(40) :: List(Foo(2)) ? In scala 2.8 rc1, I get the following output from the interactive prompt: scala> case class Foo(x:Int) defined class Foo scala> Foo(40) :: List(Foo(2)) res2: List[Foo] = List(Foo(40), Foo(2)) scala> I can go on and use it, but if someone can explain it I will be glad :)

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  • PHP5: restrict access to function to certain classes

    - by Tim
    Is there a way in PHP5 to only allow a certain class or set of classes to call a particular function? For example, let's say I have three classes ("Foo", "Bar", and "Baz"), all with similarly-named methods, and I want Bar to be able to call Foo::foo() but deny Baz the ability to make that call: class Foo { static function foo() { print "foo"; } } class Bar { static function bar() { Foo::foo(); print "bar"; } // Should work } class Baz { static function baz() { Foo::foo; print "baz"; } // Should fail } Foo::foo(); // Should also fail There's not necessarily inheritance between Foo, Bar, and Baz, so the use of protected or similar modifiers won't help; however, the methods aren't necessarily static (I made them so here for the simplicity of the example).

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  • Django ModelForm Imagefield Upload

    - by Wei Xu
    I am pretty new to Django and I met a problem in handling image upload using ModelForm. My model is as following: class Project(models.Model): name = models.CharField(max_length=100) description = models.CharField(max_length=2000) startDate = models.DateField(auto_now_add=True) photo = models.ImageField(upload_to="projectimg/", null=True, blank=True) And the modelform is as following: class AddProjectForm(ModelForm): class Meta: model = Project widgets = { 'description': Textarea(attrs={'cols': 80, 'rows': 50}), } fields = ['name', 'description', 'photo'] And the View function is: def addProject(request, template_name): if request.method == 'POST': addprojectform = AddProjectForm(request.POST,request.FILES) print addprojectform if addprojectform.is_valid(): newproject = addprojectform.save(commit=False) print newproject print request.FILES newproject.photo = request.FILES['photo'] newproject.save() print newproject.photo else: addprojectform = AddProjectForm() newProposalNum = projectProposal.objects.filter(solved=False).count() return render(request, template_name, {'addprojectform':addprojectform, 'newProposalNum':newProposalNum}) the template is: <form class="bs-example form-horizontal" method="post" action="">{% csrf_token %} <h2>Project Name</h2><br> {{ addprojectform.name }}<br> <h2>Project Description</h2> {{ addprojectform.description }}<br> <h2>Image Upload</h2><br> {{ addprojectform.photo }}<br> <input type="submit" class="btn btn-success" value="Add Project"> </form> Can anyone help me or could you give an example of image uploading? Thank you!

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  • Why boost::recursive_mutex is not working as expected?

    - by Kjir
    I have a custom class that uses boost mutexes and locks like this (only relevant parts): template<class T> class FFTBuf { public: FFTBuf(); [...] void lock(); void unlock(); private: T *_dst; int _siglen; int _processed_sums; int _expected_sums; int _assigned_sources; bool _written; boost::recursive_mutex _mut; boost::unique_lock<boost::recursive_mutex> _lock; }; template<class T> FFTBuf<T>::FFTBuf() : _dst(NULL), _siglen(0), _expected_sums(1), _processed_sums(0), _assigned_sources(0), _written(false), _lock(_mut, boost::defer_lock_t()) { } template<class T> void FFTBuf<T>::lock() { std::cerr << "Locking" << std::endl; _lock.lock(); std::cerr << "Locked" << std::endl; } template<class T> void FFTBuf<T>::unlock() { std::cerr << "Unlocking" << std::endl; _lock.unlock(); } If I try to lock more than once the object from the same thread, I get an exception (lock_error): #include "fft_buf.hpp" int main( void ) { FFTBuf<int> b( 256 ); b.lock(); b.lock(); b.unlock(); b.unlock(); return 0; } This is the output: sb@dex $ ./src/test Locking Locked Locking terminate called after throwing an instance of 'boost::lock_error' what(): boost::lock_error zsh: abort ./src/test Why is this happening? Am I understanding some concept incorrectly?

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  • Elegant way to add functionallity to previously defined functions

    - by Bastiaan
    How to combine two functions together I have a class controlling some hardware: class Heater() def set_power(self,dutycycle, period) ... def turn_on(self) ... def turn_off(self) And a class that connects to a database and handles all data logging fuctionallity for an experiment: class DataLogger() def __init__(self) # Record measurements and controls in a database def start(self,t) # Starts a new thread to aqcuire and reccord measuements every t secconds Now, in my program recipe.py I want to do something like: log = DataLogger() @DataLogger_decorator H1 = Heater() log.start(60) H1.set_power(10,100) H1.turn_on() sleep(10) H1.turn_off() etc Where all actions on H1 are recorded by the datalogger. I can change any of the classes involved, just looking for an elegant way to do this. Ideally the hardware functions remain separated from the database and DataLogger functions. And ideally the DataLogger is reusable for other controls and measurements.

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  • JUnit for Functions with Void Return Values

    - by RobotNerd
    I've been working on a Java application where I have to use JUnit for testing. I am learning it as I go. So far I find it to be useful, especially when used in conjunction with the Eclipse JUnit plugin. After playing around a bit, I developed a consistent method for building my unit tests for functions with no return values. I wanted to share it here and ask others to comment. Do you have any suggested improvements or alternative ways to accomplish the same goal? Common Return Values First, there's an enumeration which is used to store values representing test outcomes. public enum UnitTestReturnValues { noException, unexpectedException // etc... } Generalized Test Let's say a unit test is being written for: public class SomeClass { public void targetFunction (int x, int y) { // ... } } The JUnit test class would be created: import junit.framework.TestCase; public class TestSomeClass extends TestCase { // ... } Within this class, I create a function which is used for every call to the target function being tested. It catches all exceptions and returns a message based on the outcome. For example: public class TestSomeClass extends TestCase { private UnitTestReturnValues callTargetFunction (int x, int y) { UnitTestReturnValues outcome = UnitTestReturnValues.noException; SomeClass testObj = new SomeClass (); try { testObj.targetFunction (x, y); } catch (Exception e) { UnitTestReturnValues.unexpectedException; } return outcome; } } JUnit Tests Functions called by JUnit begin with a lowercase "test" in the function name, and they fail at the first failed assertion. To run multiple tests on the targetFunction above, it would be written as: public class TestSomeClass extends TestCase { public void testTargetFunctionNegatives () { assertEquals ( callTargetFunction (-1, -1), UnitTestReturnValues.noException); } public void testTargetFunctionZeros () { assertEquals ( callTargetFunction (0, 0), UnitTestReturnValues.noException); } // and so on... } Please let me know if you have any suggestions or improvements. Keep in mind that I am in the process of learning how to use JUnit, so I'm sure there are existing tools available that might make this process easier. Thanks!

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  • Jquery help : How to implement a Previous/Next & Play/Pause toggle for this script

    - by rameshelamathi
    (function($){ // Creating the sweetPages jQuery plugin: $.fn.sweetPages = function(opts){ // If no options were passed, create an empty opts object if(!opts) opts = {}; var resultsPerPage = opts.perPage || 3; var swDiv = opts.getSwDiv || "swControls"; // The plugin works best for unordered lists, althugh ols would do just as well: var ul = this; var li = ul.find('li'); li.each(function(){ // Calculating the height of each li element, and storing it with the data method: var el = $(this); el.data('height',el.outerHeight(true)); }); // Calculating the total number of pages: var pagesNumber = Math.ceil(li.length/resultsPerPage); // If the pages are less than two, do nothing: if(pagesNumber<2) return this; // Creating the controls div: //var swControls = $('<div class="swControls">'); var swControls = $('<div class='+swDiv+'>'); for(var i=0;i<pagesNumber;i++) { // Slice a portion of the lis, and wrap it in a swPage div: li.slice(i*resultsPerPage,(i+1)*resultsPerPage).wrapAll('<div class="swPage" />'); // Adding a link to the swControls div: swControls.append('<a href="" class="swShowPage">'+(i+1)+'</a>'); } ul.append(swControls); var maxHeight = 0; var totalWidth = 0; var swPage = ul.find('.swPage'); swPage.each(function(){ // Looping through all the newly created pages: var elem = $(this); var tmpHeight = 0; elem.find('li').each(function(){tmpHeight+=$(this).data('height');}); if(tmpHeight>maxHeight) maxHeight = tmpHeight; totalWidth+=elem.outerWidth(); elem.css('float','left').width(ul.width()); }); swPage.wrapAll('<div class="swSlider" />'); // Setting the height of the ul to the height of the tallest page: //ul.height(maxHeight); var swSlider = ul.find('.swSlider'); swSlider.append('<div class="clear" />').width(totalWidth); var hyperLinks = ul.find('a.swShowPage'); hyperLinks.click(function(e){ // If one of the control links is clicked, slide the swSlider div // (which contains all the pages) and mark it as active: $(this).addClass('active').siblings().removeClass('active'); swSlider.stop().animate({'margin-left':-(parseInt($(this).text())-1)*ul.width()},'slow'); e.preventDefault(); }); // Mark the first link as active the first time this code runs: hyperLinks.eq(0).addClass('active'); // Center the control div: swControls.css({ 'right':'10%', 'margin-left':-swControls.width()/2 }); return this; }})(jQuery);

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  • more radio problems * sighs * been at this for one week now

    - by jeansymolanza
    hi guys really i don't know what im doing wrong... i am trying to process multiple radios with mysql. the first step has involved me echoing the results on the process page. each time i select any radio option it simply displays the first row result. this is that i see after trying to submit the form: Notifications Thank you. The notifications have been updated successfully. statusid: 14 notc2: 1 Return this is the code for the form: <div style="padding: 15px;"> <span class="loginfail" style="font-size:24px; font-weight: bold">Notifications</span><p> <?php include("progress_insertcomment.php"); ?> <?php // Make a MySQL Connection mysql_select_db("speedycm_data") or die(mysql_error()); $query_comment = "select * from tbl_alert order by id desc limit 1"; $comment = mysql_query($query_comment, $speedycms) or die(mysql_error()); $row_comment = mysql_fetch_assoc($comment); $totalRows_comment = mysql_num_rows($comment); ?> <!--- add notification ---> <form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>"> <span id="sprytextarea1"> <textarea id='comment' name="comment" style="height: 75px; width:330px;"><?php echo $row_comment['comment']; ?></textarea> </span> <p> <button type="submit">Add</button> <input type="hidden" name="notc" value="1"/> </form> <!--- notification history ---> <form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>"> <table border="0" cellspacing="2" cellpadding="2"> <?php if ( $row_comment == 0 ) { echo "<span style='font-size: 11px;'>No current alerts.</span>"; } else { // Get all the data from the "example" table $result = mysql_query("SELECT * FROM tbl_alert ORDER BY id DESC") or die(mysql_error()); while($rows=mysql_fetch_array($result)){ ?> <tr> <td> <?php echo "<div class='bubble'><div class='pimped'> <blockquote>" . $rows['comment'] . " </blockquote></div> <cite><strong>" . $rows['user'] . "</strong> @ " . $rows['date'] . "</cite> <span style='font-size: 10px;'> <p> <a href='editalert.php?id=". $rows['id'] ."' class='form' >Edit</a>&nbsp;&#8226;&nbsp;<a href='deletealert.php?id=". $rows['id'] ."' class='form'>Delete</a> </span> </div> "; ?> </td> <td valign="top" align="center"><div style="padding-left: 30px;"><span style="font-size: 10px;">Completed?</span> <p class="field switch"> <!--- determine status of notification ---> <?php $status = $rows['status']; $id = $rows['id']; ?> <input type="radio" name="selstatus[<?php echo $id; ?>]" value="no" <?php if($status == 'yes') {echo 'checked';} else {echo '';} ?>/> <input type="radio" name="selstatus[<?php echo $id; ?>]" value="yes" <?php if($status == 'yes') {echo 'checked';} else {echo '';} ?>/> <input type="hidden" name="statusid" value="<?php echo $id; ?>"/> <label for="radio1" class="cb-enable <?php if($status == 'yes') {echo 'selected';} else {echo '';} ?>"><span>Yes</span></label> <label for="radio2" class="cb-disable <?php if($status == 'no') {echo 'selected';} else {echo '';} ?>"><span>No</span></label> </p> </div></td> </tr> <tr> <td></td> <?php } } ?> <td align="center"><div style="padding-left: 30px;"> <button type="submit">Update</button> <input type="hidden" name="notc2" value="1"/> </div></td> </tr> </table> </form> </div> this is the code for the processing page: <?php // 6) update notifications if (array_key_exists('notc2',$_POST)) { $update = $_POST['selstatus']; echo "<p style='font-size: 12px;'>Thank you. The notifications have been updated successfully.<p>"; foreach($_POST as $key => $value){ echo $key . ': ' . $value . '<br>'; } echo "<p><span style='font-size: 12px;'> <a onClick=\"history.go(-1)\" class='form'>Return</a></p> <p></span> "; exit; }; ?> how do i resolve this problem? please any help would be appreciated. i would like to display the id and value of the selected checkbox on the processing page before inserting it into the table. thanking you in advance. GOD BLESS

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  • Setting custom SQL in django admin

    - by eugene y
    I'm trying to set up a proxy model in django admin. It will represent a subset of the original model. The code from models.py: class MyManager(models.Manager): def get_query_set(self): return super(MyManager, self).get_query_set().filter(some_column='value') class MyModel(OrigModel): objects = MyManager() class Meta: proxy = True Now instead of filter() I need to use a complex SELECT statement with JOINS. What's the proper way to inject it wholly to the custom manager?

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  • JQuery quiz app - use <id> tag to toggle variable on/off

    - by hairyllama
    Hi, I am writing a jquery phonegap quiz app and have a number of categories from which a user can select via checkbox. Relevant questions belonging to those categories are then returned. However, I have two huge switch statements to change the relevant variables from 0 to 1 if the checkbox for that category is selected and vice versa (this info is used to build a compound db query). The value of the variable behind the checkbox is only ever 0 or 1, so is there a better way to do this? My HTML is: <h2>Categories</h2> <ul class="rounded"> <li>Cardiology<span class="toggle"><input type="checkbox" id="cardiology" /></span></li> <li>Respiratory<span class="toggle"><input type="checkbox" id="respiratory" /></span></li> <li>Gastrointestinal<span class="toggle"><input type="checkbox" id="gastrointestinal" /></span></li> <li>Neurology<span class="toggle"><input type="checkbox" id="neurology" /></span></li> </ul> My Javascript is along the lines of: var toggle_cardiology = 0; var toggle_respiratory = 0; var toggle_gastrointestinal = 0; var toggle_neurology = 0; $(function() { $('input[type="checkbox"]').bind('click',function() { if($(this).is(':checked')) { switch (this.id) { case "cardiology": toggle_cardiology = 1; break; case "respiratory": toggle_respiratory = 1; break; case "gastrointestinal": toggle_gastrointestinal = 1; break; case "neurology": toggle_neurology = 1; break; etc. (which is cumbersome with 10+ categories plus an else statement with a switch to change them back) I'm thinking of something along the lines of concatenating the HTML id tag onto the "toggle_" prefix - in pseudocode: if (toggle_ + this.id == 1){ toggle_ + this.id == 0} if (toggle_ + this.id == 0){ toggle_ + this.id == 1} Thanks, Nick.

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  • Dynamic, reflective SignalHandler in Java

    - by pilcrow
    How do I install signal handling logic iff sun.misc.Signal is available? Background First generation of my code looked something like this: class MyApp { public static void main(String[] args) { ... Signal.handle(term_sig, new SignalHandler() { public void handle(Signal sig) { ... } }); ... } } I believe I understand how to reflectively test for and use signal handlers -- Class.forName("sun.misc.Signal"), reflectively call Signal.handle, and so forth. My impulse was simply to instantiate another anonymous inner class with the dynamically obtained SignalHandler class, but I think that's just wishful syntax.

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  • How can I find all items beginning with a or â?

    - by Malcolm Frexner
    I have a list of items that are grouped by their first letter. By clicking a letter the user gets alle entries that begin with that letter. This does not work for french. If I choose the letter a, items with â are not returned. What is a good way to return items no matter if they have an accent or not? <% char alphaStart = Char.Parse("A"); char alphaEnd = Char.Parse("Z"); %> <% for (char i = alphaStart; i <= alphaEnd; i++) { %> <% char c = i; %> <% var abcList = Model.FaqList.Where(x => x.CmsHeader.StartsWith(c.ToString())).ToList(); %> <% if (abcList.Count > 0 ) { %> <div class="naviPkt"> <a id="<%= i.ToString().ToUpper() %>" class="naviPktLetter" href="#<%= i.ToString().ToLower() %>"><%= i.ToString().ToUpper() %></a> </div> <ul id="menuGroup<%= i.ToString().ToUpper() %>" class="contextMenu" style="display:none;"> <% foreach (var info in abcList) { %> <li class="<%= info.CmsHeader%>"> <a id="infoId<%= info.CmsInfoId%>" href="#<%= info.CmsInfoId%>" class="abcEntry"><%= info.CmsHeader%></a> </li> <% } %> </ul> <% } %> <% } %>

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  • Getting list of fields back from 'use fields' pragma?

    - by makenai
    So I'm familiar with the use fields pragma in Perl that can be used to restrict the fields that are stored in a class: package Fruit; use fields qw( color shape taste ); sub new { my ( $class, $params ) = @_; my $self = fields::new( $class ) unless ref $class; foreach my $name ( keys %$params ) { $self->{ $name } = $params->{ $name }; } return $self; } My question is.. once I've declared the fields at the top, how I can get the list back.. say because I want to generate accessors dynamically? Is keys %FIELDS the only way? Secondarily, is there a more efficient way to pre-populate the fields in the constructor than looping through and assigning each parameter as I am above? Thanks!

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  • How to deserialize an html div when it has certain attributes to it?

    - by user1676874
    For example this: <div class="link_text"> <a href="http://www.stackoverflow.com"> <strong>Text</strong></a> </div> With normal tags like XML ones it is easy, you just create the class with the same name as the tag, so if the tag is: <something></something> you create a class called something, but how would you do this in HTML in an example div such as that one, with a class attribute inside?

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  • Speed comparison - Template specialization vs. Virtual Function vs. If-Statement

    - by Person
    Just to get it out of the way... Premature optimization is the root of all evil Make use of OOP etc. I understand. Just looking for some advice regarding the speed of certain operations that I can store in my grey matter for future reference. Say you have an Animation class. An animation can be looped (plays over and over) or not looped (plays once), it may have unique frame times or not, etc. Let's say there are 3 of these "either or" attributes. Note that any method of the Animation class will at most check for one of these (i.e. this isn't a case of a giant branch of if-elseif). Here are some options. 1) Give it boolean members for the attributes given above, and use an if statement to check against them when playing the animation to perform the appropriate action. Problem: Conditional checked every single time the animation is played. 2) Make a base animation class, and derive other animations classes such as LoopedAnimation and AnimationUniqueFrames, etc. Problem: Vtable check upon every call to play the animation given that you have something like a vector<Animation>. Also, making a separate class for all of the possible combinations seems code bloaty. 3) Use template specialization, and specialize those functions that depend on those attributes. Like template<bool looped, bool uniqueFrameTimes> class Animation. Problem: The problem with this is that you couldn't just have a vector<Animation> for something's animations. Could also be bloaty. I'm wondering what kind of speed each of these options offer? I'm particularly interested in the 1st and 2nd option because the 3rd doesn't allow one to iterate through a general container of Animations. In short, what is faster - a vtable fetch or a conditional?

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  • How do I differentiate between different descendents with the same name?

    - by zotty
    I've got some XML I'm trying to import with c#, which looks something like this: <run> <name = "bob"/> <date = "1958"/> </run> <run> <name = "alice"/> <date = "1969"/> </run> I load my xml using XElement xDoc=XElement.Load(filename); What I want to do is have a class for "run", under which I can store names and dates: public class RunDetails { public RunDetails(XElement xDoc, XNamespace xmlns) { var query = from c in xDoc.Descendants(xmlns + "run").Descendants(xmlns + "name") select c; int i=0; foreach (XElement a in query) { this.name= new NameStr(a, xmlns); // a class for names Name.Add(this.name); //Name is a List<NameStr> i++; } // Here, i=2, but what I want is a new instance of the RunDetails class for each <run> } } How can I set up my code to create a new instance of the RunDetails class for every < run, and to only select the < name and < date inside a given < run?

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  • Django: How can I add weight/ordering to a many to many relationship?

    - by Klaas van Schelven
    I'm having Pages with TextBlocks on them. Text Blocks may appear on different pages, pages may have several text blocks on them. Every page may have these blocks in an ordering of it's own. This can be solved by using a separate through parameter. Like so: class TextBlock(models.Model): title = models.CharField(max_length=255) text = models.TextField() class Page(models.Model): textblocks = models.ManyToManyField(TextBlock, through=OrderedTextBlock) class OrderedTextBlock(models.Model): text_block = models.ForeignKey(TextBlock) product_page = models.ForeignKey(ProductPage) weight = models.IntegerField() class Meta: ordering = ('weight',) But I'm not very enthousiastic about the violations of DRY for my app. (There's a lot of ordered ManyToMany relations). Is there a recommended way to go about this?

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  • Is there a way to know if std::chrono::monotonic_clock is defined?

    - by Vicente Botet Escriba
    C++0X N3092 states that monotonic_clock is optional. 20.10.5.2 Class monotonic_clock [time.clock.monotonic] 1 Objects of class monotonic_clock represent clocks for which values of time_point never decrease as physical time advances. monotonic_clock may be a synonym for system_clock if system_clock::is_monotonic is true. ** 2 The class monotonic_clock is conditionally supported.** Is there a way using SFINAE or another technique to define a traits class that states if monotonic_clock is defined? struct is_monotonic_clock_defined; If yes, how? If not, shouldn't the standard define macro that gives this information at preprocessing time?

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