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  • PHP: How to Pass child class __construct() arguments to parent::__construct() ?

    - by none
    I have a class in PHP like so: class ParentClass { function __construct($arg) { // Initialize a/some variable(s) based on $arg } } It has a child class, as such: class ChildClass extends ParentClass { function __construct($arg) { // Let the parent handle construction. parent::__construct($arg); } } What if, for some reason, the ParentClass needs to change to take more than one optional argument, which I would like my Child class to provide "just in case"? Unless I re-code the ChildClass, it will only ever take the one argument to the constructor, and will only ever pass that one argument. Is this so rare or such a bad practice that the usual case is that a ChildClass wouldn't need to be inheriting from a ParentClass that takes different arguments? Essentially, I've seen in Python where you can pass a potentially unknown number of arguments to a function via somefunction(*args) where 'args' is an array/iterable of some kind. Does something like this exist in PHP? Or should I refactor these classes before proceeding?

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  • C++ Forward declaration for virtual function

    - by Gokul
    Hi, I have a class hierarchy and i am writing a virtual function in it. Say there are three classes class A { virtual A* test(); }; ( File A.h ) class B : public A { virtual C* test(); }; ( File B.h ) class C : public A {}; ( File C.h ) Now is it possible for me to avoid including C.h in B.h, by doing some kind of forward declaration saying that C is a sub-class of A? Thanks, Gokul.

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  • Inheritance and Implicit Type Casting

    - by Josué Molina
    Suppose I have the following three classes: class Animal {}; class Human : public Animal {}; class Dog : public Animal { public: void setOwner(Animal* owner) { this->owner = owner; } private: Animal* owner; }; Why is the following allowed, and what exactly is happening? Dog d; Human h; d.setOwner(&h); // ? At first, I tried to cast it like this d.setOwner(&(Animal)h), but the compiler gave me a warning, and I hit a run-time error. Edit: the warning the compiler gave me was "taking address of temporary". Why is this so?

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  • Problem accessing base member in derived constructor

    - by LeopardSkinPillBoxHat
    Given the following classes: class Foo { struct BarBC { protected: BarBC(uint32_t aKey) : mKey(aKey) mOtherKey(0) public: const uint32_t mKey; const uint32_t mOtherKey; }; struct Bar : public BarBC { Bar(uint32_t aKey, uint32_t aOtherKey) : BarBC(aKey), mOtherKey(aOtherKey) // Compile error here }; }; I am getting a compilation error at the point indicated: error: class `Foo::Bar' does not have any field named `mOtherKey'. Can anyone explain this? I suspect it's a syntactical problem due to my Bar class being defined within the Foo class, but can't seem to find a way around it. This is simple public inheritance, so mOtherKey should be accessible from the Bar constructor. Right? Or is it something to do with the fact that mOtherKey is const and I have already initialised it to 0 in the BarBC constructor?

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  • How do I create a point system in a Rails/Twitter app that assigns points to users and non-authentic

    - by codyvbrown
    I'm building a question and answer application on top of twitter and I'm hitting some snags because I'm inevitably dealing with two classes of users: authenticated and non-authenticated. The site enable users to give points to other users, who may or may not be authenticated, and I want to create a site-wide point system where the application stores and displays this information on their profile. I want to save this point data to the user because that would be faster and more efficient but non-authenticated users aren't in our system, we only have the twitter handle. So instead we display the points in our system like this: @points = point.all( :select => "tag, count(*) AS count", # Return tag and count :group => 'tag', # Group by the tag :order => "2 desc", :conditions => {:twitter_handle => params[:username]}) Is there a better way to do this? Is there a better way to associate data with non-authenticated users?

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  • C++ initializing constants and inheritance

    - by pingvinus
    I want to initialize constant in child-class, instead of base class. And use it to get rid of dynamic memory allocation (I know array sizes already, and there will be a few child-classes with different constants). So I try: class A { public: const int x; A() : x(0) {} A(int x) : x(x) {} void f() { double y[this->x]; } }; class B : A { B() : A(2) {} }; Pretty simple, but compiler says: error C2057: expected constant expression How can I say to compiler, that it is really a constant?

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  • Navigation properties not set when using ADO.NET Mocking Context Generator

    - by olenak
    I am using ADO.NET Mocking Context Generator plugin for my Entity Framework model. I have not started on using mocks yet, just trying to fix generated entity and context classes to make application run as before without exceptions. I've already fixed T4 template to support SaveChanges method. Now I've got another problem: when I try to access any navigation property it is set to null. All the primitive fields inherited from DB table are set and correct. So what I am doing is the following using (var context = MyContext()) { var order = context.Orders.Where(p => p.Id == 7); var product = order.Products; } in this case product is set to null. But that was not a case while using default code generator, it used to return real product object. Thanks ahead for any suggestions!

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  • Class interaction

    - by user1264391
    Ok so I'm doing a simulation about a "Mall" I have many classes in the same "level" which corresponds to each person's personality. For example I have the class: clown, thief, assassin, materialist, etc. in the same level And a father class called Clients. In the Client class I have some methods for eating,walking, etc. and each specific class has a specific method, the thief steals, assassin kills, etc. I was wondering how could I put every "client" in a list and still cast every specific method?

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  • Python unittest with expensive setup

    - by Staale
    My test file is basically: class Test(unittest.TestCase): def testOk(): pass if __name__ == "__main__": expensiveSetup() try: unittest.main() finally: cleanUp() However, I do wish to run my test through Netbeans testing tools, and to do that I need unittests that don't rely on an environment setup done in main. Looking at http://stackoverflow.com/questions/402483/caching-result-of-setup-using-python-unittest - it recommends using Nose. However, I don't think Netbeans supports this. I didn't find any information indicating that it does. Additionally, I am the only one here actually writing tests, so I don't want to introduce additional dependencies for the other 2 developers unless they are needed. How can I do the setup and cleanup once for all the tests in my TestSuite? The expensive setup here is creating some files with dummy data, as well as setting up and tearing down a simple xml-rpc server. I also have 2 test classes, one testing locally and one testing all methods over xml-rpc.

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  • C++ memory management of reference types

    - by Russel
    Hello, I'm still a fairly novice programmer and I have a question about c++ memory management with refence types. First of all, my understanding of reference types: A pointer is put on the stack and the actual data that the pointer points to is created and placed on the heap. Standard arrays and user defined classes are refence types. Is this correct? Second, my main question is do c and c++'s memory management mechanisms (malloc, free and new, delete) always handle this properly and free the memory that a class or array is pointing to? Does everything still work if those pointers get reassigned somehow to other objects of the same size/type on the heap? What if a class has a pointer member that points to another object? I am assuming that delete/freeing the class object doesn't free what it's member pointer points to, is that correct? Thanks all! -R

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  • Java CRTP: Works for container but not for methods?

    - by Daniel
    I have a baseclass with a protected static ArrayList. I want to have a seperate ArrayList for each kind of subclass that extends this baseclass. This is when I applied CRTP: public class BaseExample<T> { protected static ArrayList<Integer> data = new ArrayList<Integer>(); } This works just fine. However, when I try to implement the following static method in the same base class, it doesn't adhere to CRTP: public static void clear() { data.clear(); } For example: class SubExample extends BaseExample<SubExample> { // insertion methods accessing 'data' field // these work fine :) } SubExample.clear(); // does not seem to clear data container Do I need to somehow explicitly specify T in my baseclass clear method? Note: These are all pure static classes.

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  • Is the a pattern for iterating over lists held by a class (dynamicly typed OO languages)

    - by Roman A. Taycher
    If I have a class that holds one or several lists is it better to allow other classes to fetch those lists(with a getter) or to implement a doXList/eachXList type method for that list that take a function and call that function on each element of the list contained by that object. I wrote a program that did a ton of this and I hated passing around all these lists sometimes with method in class a calling method in class B to return lists contained in class C, B contains a C or multiple C's (note question is about dynamically typed OO languages languages like ruby or smalltalk) ex. (that came up in my program) on a Person class containing scheduling preferences and a scheduler class needing to access them.

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  • Using a proxy for NSURLConnection

    - by SideSwipe
    Is there any way to get the content of a webfile (namely a .html Document) using a proxy, which is not defined in the system settings? I know that NSURLConnection is the right way to download a web file into a variable and not into a file (for which we should use NSURLDownload), but I don't find a way to use a proxy for it. Are there some unofficial APIs, Libraries or Classes or such I could use for what I want to do? I'm not that pro in Mac Programming, so I'm searching for something more or less simple. SideSwipe

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  • Need a good way to share iPhone source code on the Web.

    - by CJCraft.com
    Hi, I'm looking for a way to share some iPhone SDK source code I have with others. Goals: Share iPhone SDK source code, Objective C written in XCode. I have a good bit of source code I want to share. I'd like for it to be easy. I'd like for it to have syntax highlighting, by this I mean coloring and formatting Ideally it would allow me some room to make it "fit" into my site. I want it to look like basically another page on my site where the content is the code. It shouldn't be just a text file in other words. Here's an example where someone was able to do this for C#: http://www.opennetcf.com/library/sdf/ I guess what I want is the ability to create html documentation for all the classes, etc.

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  • Is there a way to reference a certain class/interface/... by enclosing it with its namespace rather than a using directive "using namespace_name" ?!

    - by Ahmed
    Is there a way to reference a certain class/interface/... by enclosing it with its namespace rather than a using directive "using namespace_name" ?! As, I'm working on a website, which uses SAP .NET connector. I already added a reference for connector ddl, and while referencing its namespace "using namespace_name", or set class namespace to another one rather than connector namespace, I got error regarding connector classes with that error message "The type or namespace couldn't be found, are you missing a using directive or an assembly reference?". But while changing namespace name to connector namespace, everything is going well?! // Set namespace to be IDestinationConfiguration interface namespace. namespace SAP.Middleware.Connector { public class ConnectorConfiguration : IDestinationConfiguration { } } So, connector types forced me to set namespace of class to their namespace! Is this possible? If so, how?

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  • Parent-Child relation while using object data source

    - by Saba
    Hello guys I am experiencing with a class generator I've written, which generates a class for each table in database with each table field as a property and such. Before that, I used to add a typed dataset to the project and add some tables to it. It automatically detected the relationship between tables and when I added a parent table as data source of a datagrid, I could add another datagrid and use the foreing key data member of it's bindingsource to fill it, and when someone moved the focus on parent datagrid, the data in child datagrid would change accordingly. Now that I have my classes, I add an object as data source for my 2 datagrids, but obviously it doesn't detect a parent child relation. But It'd really help if I could have that foreign key relation in my object datasources. Is there any way to have that relation in object datasource?

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  • Including a List<SpecificType> in a model, and how to populate it

    - by Ray Sülzer
    I currently have two Model classes: class Leaders: List<Leaders> { public string LeaderName { get; set; } public string PrecintName { get; set; } } public class MarketReport { //A list of activists public Leaders leaderlist { get; set; } } Now, I have no idea if I am doing the above correctly, but I want to populate the list within the MarketReport foreach (var store in stores) { MarketReport.leaderlist.AddItem //I want to add an item of type Leader to the list //so that I can pass it to MVC view }

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  • Easiest way to get an NSDate representation of "the next 7am that will occur" in Cocoa?

    - by Drarok
    I figure I can achieve what I want by using NSCalendar and NSDateComponents, but that would run something like the following: Get "now" Create an NSDateComponents from "now". If "now" is pre-7am, then use today's date. If "now" is post-7am, use tomorrow's date. If today is the last day of the month, increase month, set day to 1. If it was December, increase year by 1 also. Set hour, minute, second. Create a new NSDate. It all seems very long-winded, but that appears to be what other answers on here suggest, and the documentation doesn't offer any clues. I'm going back and forth between all the date and calendar classes I can find. Is there a simple way to ask for the "next occurring 7am" ? Thanks.

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  • Extract object (*.o) files from an iPhone static library

    - by Brett
    I have a set of iPhone static libraries (a *.a file) in which I only call a few of the classes from. I have used AR in the past (with linux libraries) to extract the object files from the static library, remove the unwanted object files and rearchive. However, when I try this with an iPhone compliled static library, I get the following error: ar: CustomiPhoneLib.a is a fat file (use libtool(1) or lipo(1) and ar(1) on it) ar: CustomiPhoneLib.a: Inappropriate file type or format Does anyone know how to extract the object files from an iphone compiled static library? Doing thie could potentially reduce the final file size.

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  • Confused about "override" vs. "new" in C#

    - by iTayb
    I'm having the following classes: class Base { public virtual void Print() { Console.WriteLine("Base"); } } class Der1 : Base { public new virtual void Print() { Console.WriteLine("Der1"); } } class Der2 : Der1 { public override void Print() { Console.WriteLine("Der2"); } } This is my main method: Base b = new Der2(); Der1 d1 = new Der2(); Der2 d2 = new Der2(); b.Print(); d1.Print(); d2.Print(); The output is Base, Der2, Der2. As far as I know, Override won't let previous method to run, even if the pointer is pointing to them. So the first line should output Der2 as well. However Base came out. How is it possible? How the override didn't work there?

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  • How do I create a point system in a Rails app that assigns points to users and non-authenticated-use

    - by codyvbrown
    I'm building a question and answer application on top of twitter and I'm hitting some snags because I'm inevitably dealing with two classes of users: authenticated and non-authenticated. The site enable users to give points to other users, who may or may not be authenticated, and I want to create a site-wide point system where the application stores and displays this information on their profile. I want to save this point data to the user because that would be faster and more efficient but non-authenticated users aren't in our system, we only have the twitter handle. So instead we display the points in our system like this: @points = point.all( :select => "tag, count(*) AS count", # Return tag and count :group => 'tag', # Group by the tag :order => "2 desc", :conditions => {:twitter_handle => params[:username]}) Is there a better way to do this? Is there a better way to associate data with non-authenticated users?

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  • [jQuery] Change the content of a cell from another cell

    - by robs
    hey, i'm trying to select change the content of a cell with jquery but i cant seem to get it working. lets say we have this table: <table border="1"> <tr> <td>cell 1 <td>cell 2 <td>cell 3 <tr> <td>cell 4 <td>cell 5 <td>cell 6 <a onclick="javascript:$(this).parent().parent().('td').html('test');">Click</a> <tr> <td>cell 7 <td>cell 8 <td>cell 9 </table> i want to change the content of cell 4 from within cell 6. the ('td') obviously isnt working. how can i access cell 4 from cell 6 without the use of classes or ids? thanks in advance

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  • Serialization of an object and its Contained Objects

    - by Amit
    There is a main class having 2 subClasses(each represent separate entity) and all classes needs to be serialized.. how should I proceed ? My requirement is when I serelize MainClass, I should get the xml for each sub class and main class as well. Thanks in advance... and if my approach is incorrect... correct that as well.. Ex given below... class MainClass { SubClass1 objSubclass1 = null; SubClass2 objSubclass2 = null; public MainClass() { objSubclass1 = new SubClass1(); objSubclass2 = new SubClass2(); } [XmlElement("SubClass1")] public SubClass1 SubClass1 {get {return objSubclass1;} } [XmlElement("SubClass2")] public SubClass2 SubClass2 {get {return objSubclass2;} } } Class SubClass1 { Some properties here... } Class SubClass2 { Some properties here... }

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  • How do I change the JAVA_HOME for ant?

    - by Eugene M
    I'm doing java work on a class server where I don't have root. Whenever I try to compile using ant, it points to the wrong directory (/usr/tomcat instead of /usr/tomcat/jre ). One of the things we were told to do when setting up our user accounts was to add export JAVA_HOME=/usr/tomcat/jre to the .bashrc file. I don't know if that was supposed to take care of the problem but it doesn't seem to. So, how can I change the JAVA_HOME property for ant but only for when I run ant? EDIT: echo $JAVA_HOME points to /usr/tomcat/jre echo $JAVA_HOME\bin points to /usr/tomcat/jrebin The problem is when I normally run ant I get this error: Unable to locate tools.jar. Expected to find it in /usr/tomcat/lib/tools.jar Buildfile: build.xml compile: [javac] Compiling 1 source file to /home/ejm244/build/classes BUILD FAILED /home/ejm244/build.xml:9: Unable to find a javac compiler; com.sun.tools.javac.Main is not on the classpath. Perhaps JAVA_HOME does not point to the JDK Total time: 0 seconds

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  • I can't change a value, for a web service using an axiom client!

    - by adrian7
    Hi.I just started learning about web serices. I succesfuly installed Tomcat, and deployed axis2 on it. I followed the tutorial from here http://ws.apache.org/axis2/1_1_1/quickstartguide.html . I made the StockQuoteService web service, moved the .aar file in the WEB-INF/services folder and tested it - it worked all fine. Then I made a client for the servce. I took the source code of the file AXIOMClient.java from the dir described here http://ws.apache.org/axis2/1_1_1/quickstartguide.html#clientaxiom , imported the classes in Eclipse Java IDE and runned it. I tested and the update method works from the browser when calling http://localhost:8080/axis2/services/StockQuoteService/update?symbol=WSO&price=144 But from my java client update method is not working at all, when calling getPrice I always receive 42.00. What am I doing wrong? or, how can I trace what is happening?

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