Search Results

Search found 4593 results on 184 pages for 'constructor injection'.

Page 72/184 | < Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >

  • How does the method overload resolution system decide which method to call when a null value is passed?

    - by Joan Venge
    So for instance you have a type like: public class EffectOptions { public EffectOptions ( params object [ ] options ) {} public EffectOptions ( IEnumerable<object> options ) {} public EffectOptions ( string name ) {} public EffectOptions ( object owner ) {} public EffectOptions ( int count ) {} public EffectOptions ( Point point ) {} } Here I just give the example using constructors but the result will be the same if they were non-constructor methods on the type itself, right? So when you do: EffectOptions options = new EffectOptions (null); which constructor would be called, and why? I could test this myself but I want to understand how the overload resolution system works (not sure if that's what it's called).

    Read the article

  • std::map default value for build-in type

    - by Qifa Zhao
    Recently, I was confused by the std::map operator[] function. In the MSDN library, it says: "If the argument key value is not found, then it is inserted along with the default value of the data type." I tryed to search much more exactly explanation for this issue. For example here: std::map default value In this page, Michael Anderson said that "the default value is constructed by the default constructor(zero parameter constructor)". Now my quest comes to this:"what the default value for the build-in type?". Was it compiler related? Or is there a standard for this issue by the c++ stardard committee? I did a test on visual studio 2008 for the "int" type, and found the "int" type is construted with the value 0.

    Read the article

  • Can't Instantiate Windsor Custom Component Activator

    - by jeffn825
    Hi, I'm getting an exception calling Resolve: KernelException: Could not instantiate custom activator Inner Exception: {"Constructor on type 'MyProj.MyAdapter`1[[MyProj.MyBusinessObject, MyAsm, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]' not found."} There's definitely a public parameterless constructor there (and I've verified this using reflection at runtime)...so I figure the problem might have to do with the fact that it's generic? I've tried getting the component model object and setting RequiresGenericArguments to true, but that hasn't gotten me anywhere. Any help would be much appreciated! Thanks.

    Read the article

  • Unique_ptr compiler errors

    - by Godric Seer
    I am designing and entity-component system for a project, and C++ memory management is giving me a few issues. I just want to make sure my design is legitimate. So to start I have an Entity class which stores a vector of Components: class Entity { private: std::vector<std::unique_ptr<Component> > components; public: Entity() { }; void AddComponent(Component* component) { this -> components.push_back(std::unique_ptr<Component>(component)); } ~Entity(); }; Which if I am not mistaken means that when the destructor is called (even the default, compiler created one), the destructor for the Entity, will call ~components, which will call ~std::unique_ptr for each element in the vector, and lead to the destruction of each Component, which is what I want. The component class has virtual methods, but the important part is its constructor: Component::Component(Entity parent) { parent.addComponent(this) // I am not sure if this would work like I expect // Other things here } As long as passing this to the method works, this also does what I want. My confusion is in the factory. What I want to do is something along the lines of: std::shared_ptr<Entity> createEntity() { std::shared_ptr<Entity> entityPtr(new Entity()); new Component(*parent); // Initialize more, and other types of Components return entityPtr; } Now, I believe that this setup will leave the ownership of the Component in the hands of its Parent Entity, which is what I want. First a small question, do I need to pass the entity into the Component constructor by reference or pointer or something? If I understand C++, it would pass by value, which means it gets copied, and the copied entity would die at the end of the constructor. The second, and main question is that code based on this sample will not compile. The complete error is too large to print here, however I think I know somewhat of what is going on. The compiler's error says I can't delete an incomplete type. My Component class has a purely virtual destructor with an implementation: inline Component::~Component() { }; at the end of the header. However since the whole point is that Component is actually an interface. I know from here that a complete type is required for unique_ptr destruction. The question is, how do I work around this? For reference I am using gcc 4.4.6.

    Read the article

  • Immutability of big objects

    - by Malax
    Hi StackOverflow! I have some big (more than 3 fields) Objects which can and should be immutable. Every time I run into that case i tend to create constructor abominations with long parameter lists. It doesn't feel right, is hard to use and readability suffers. It is even worse if the fields are some sort of collection type like lists. A simple addSibling(S s) would ease the object creation so much but renders the object mutable. What do you guys use in such cases? I'm on Scala and Java, but i think the problem is language agnostic as long as the language is object oriented. Solutions I can think of: "Constructor abominations with long parameter lists" The Builder Pattern Thanks for your input!

    Read the article

  • Java: Non-static nested classes and instance.super()

    - by Kiv
    I'm having a hard time wrapping my head around non-static nested classes in Java. Consider the following example, which prints "Inner" and then "Child". class Outer { class Inner { Inner() { System.out.println("Inner"); } } } public class Child extends Outer.Inner { Child(Outer o) { o.super(); System.out.println("Child"); } public static void main(String args[]) { new Child(new Outer()); } } I understand that instances of Inner always have to be associated with an Outer instance, and that that applies to Child too since it extends Inner. My question is what the o.super() syntax means - why does it call the Inner constructor? I've only seen a plain super(args) used to call the superclass constructor and super.method() to call the superclass version of an overridden method, but never something of the form instance.super().

    Read the article

  • static array in c++ forgets its size

    - by Karel Bílek
    In this small example, c++ forgets size of an array, passed to a constructor. I guess it is something simple, but I cannot see it. In classes.h, there is this code: #ifndef CLASSES_INC #define CLASSES_INC #include <iostream> class static_class { public: static_class(int array[]) { std::cout<<sizeof(array)/sizeof(int)<<"\n"; } }; class my_class{ public: static static_class s; static int array[4]; }; #endif In classes.cpp, there is this code: #include "classes.h" int my_class::array[4]={1, 2, 3, 4}; static_class my_class::s = static_class(my_class::array); In main.cpp, there is only simple #include "classes.h" int main () { return 0; } Now, the desired output (from the constructor of static_class) is 4. But what I get is 1. Why is that?

    Read the article

  • ThreadPool.QueueUserWorkItem new Form CreateHandle Deadlock

    - by bogdanbrudiu
    I have a thread that needs to create a popup Window. I start the thread using ThreadPool.QueueUserWorkItem(new WaitCallback(CreatePopupinThread)) Thew thread creats a new form. The application freases in the new Form constructor at CreateHandle. The Worker Thread is locked... How can I fix this? this is how I create the form var form = new ConfirmationForm { Text = entry.Caption, Label = entry.Text, }; In the constructor the thread enters a deadlock public ConfirmationForm() { InitializeComponent(); }

    Read the article

  • WordPress front page (homepage) fails to redirect when static front page is set.

    - by Keyslinger
    I have configured WordPress to display a static front page as described here: http://codex.wordpress.org/Settings_Reading_SubPanel#Reading_Settings When save changes and try to visit my front page, my browser displays the following error: "The page isn't redirecting properly. Firefox has detected that the server is redirecting the request for this address in a way that will never complete." Disabling cookies does not remedy the situation. I'm using the theme, Constructor (http://wordpress.org/extend/themes/constructor), which I suspect may be contributing to the problem. How can I make WordPress properly display my front page?

    Read the article

  • Initialization of components with interdependencies - possible antipattern?

    - by Rosarch
    I'm writing a game that has many components. Many of these are dependent upon one another. When creating them, I often get into catch-22 situations like "WorldState's constructor requires a PathPlanner, but PathPlanner's constructor requires WorldState." Originally, this was less of a problem, because references to everything needed were kept around in GameEngine, and GameEngine was passed around to everything. But I didn't like the feel of that, because it felt like we were giving too much access to different components, making it harder to enforce boundaries. Here is the problematic code: /// <summary> /// Constructor to create a new instance of our game. /// </summary> public GameEngine() { graphics = new GraphicsDeviceManager(this); Components.Add(new GamerServicesComponent(this)); //Sets dimensions of the game window graphics.PreferredBackBufferWidth = 800; graphics.PreferredBackBufferHeight = 600; graphics.ApplyChanges(); IsMouseVisible = true; screenManager = new ScreenManager(this); //Adds ScreenManager as a component, making all of its calls done automatically Components.Add(screenManager); // Tell the program to load all files relative to the "Content" directory. Assets = new CachedContentLoader(this, "Content"); inputReader = new UserInputReader(Constants.DEFAULT_KEY_MAPPING); collisionRecorder = new CollisionRecorder(); WorldState = new WorldState(new ReadWriteXML(), Constants.CONFIG_URI, this, contactReporter); worldQueryUtils = new WorldQueryUtils(worldQuery, WorldState.PhysicsWorld); ContactReporter contactReporter = new ContactReporter(collisionRecorder, worldQuery, worldQueryUtils); gameObjectManager = new GameObjectManager(WorldState, assets, inputReader, pathPlanner); worldQuery = new DefaultWorldQueryEngine(collisionRecorder, gameObjectManager.Controllers); gameObjectManager.WorldQueryEngine = worldQuery; pathPlanner = new PathPlanner(this, worldQueryUtils, WorldQuery); gameObjectManager.PathPlanner = pathPlanner; combatEngine = new CombatEngine(worldQuery, new Random()); } Here is an excerpt of the above that's problematic: gameObjectManager = new GameObjectManager(WorldState, assets, inputReader, pathPlanner); worldQuery = new DefaultWorldQueryEngine(collisionRecorder, gameObjectManager.Controllers); gameObjectManager.WorldQueryEngine = worldQuery; I hope that no one ever forgets that setting of gameObjectManager.WorldQueryEngine, or else it will fail. Here is the problem: gameObjectManager needs a WorldQuery, and WorldQuery needs a property of gameObjectManager. What can I do about this? Have I found an anti-pattern?

    Read the article

  • Asp .Net MVC Viewmodel should be class or struct?

    - by Jonas Everest
    Hey guys, I have just been thinking about the concept of view model object we create in asp.net MVC. Our purpose is to instantiate it and pass it from controller to view and view read it and display the data. Those view model are usually instantiated through constructor. We won't need to initialize the members, we may not need to redefine/override parameterless constructor and we don't need inheritance feature there. So, why don't we use struct type for our view model instead of class. It will enhance the performance.

    Read the article

  • How to make some functions of a class as private for third level of inheritance.

    - by Shantanu Gupta
    I have created a class say A which has some functions defined as protected. Now Class B inherits A and class C inherits B. Class A has private default constructor and protected parameterized constructor. I want Class B to be able to access all the protected functions defined in Class A but class C can have access on some of the functions only not all the functions and class C is inheriting class B. How can I restrict access to some of the functions of Class A from Class C ? Class A { private A(){} protected A(int ){} protected calc(){} protected allow(){} } Class B : A {} // calc() and allow() should be accessible here CLass C:B { // calc() should not be accessible here but allow() should be accessible here. }

    Read the article

  • Workaround for abstract attributes in Java

    - by deamon
    In Scala I would write an abstract class with an abstract attribute path: abstract class Base { val path: String } class Sub extends Base { override val path = "/demo/" } Java doesn't know abstract attributes and I wonder what would be the best way to work around this limitation. My ideas: a) constructor parameter abstract class Base { protected String path; protected Base(String path) { this.path = path; } } class Sub extends Base { public Sub() { super("/demo/"); } } b) abstract method abstract class Base { // could be an interface too abstract String getPath(); } class Sub extends Base { public String getPath() { return "/demo/"; } } Which one do you like better? Other ideas? I tend to use the constructor since the path value should not be computed at runtime.

    Read the article

  • Can FileOutputStream() take a relative path as an argument

    - by Ankur
    I am creating a FileOutputStream object. It takes a file or String as an argument in its constructor. My question is, can I give it a relative URL as an argument for the location of a file, it doesn't seem to work, but I am trying to work out if this is possible at all (if not I will stop trying). If it is not possible, how can I (from a servlet) get the absolute path (on the filesystem, not the logical URL) to the current location in such a way that I can pass that to the constructor. Part of my problem is that my dev box is Windows but I will publish this to a Unix box, so the paths cannot be the same i.e. on Windows C:/.... and on unix /usr/...

    Read the article

  • Custom Memory Allocator for STL map

    - by Prasoon Tiwari
    This question is about construction of instances of custom allocator during insertion into a std::map. Here is a custom allocator for std::map<int,int> along with a small program that uses it: #include <stddef.h> #include <stdio.h> #include <map> #include <typeinfo> class MyPool { public: void * GetNext() { return malloc(24); } void Free(void *ptr) { free(ptr); } }; template<typename T> class MyPoolAlloc { public: static MyPool *pMyPool; typedef size_t size_type; typedef ptrdiff_t difference_type; typedef T* pointer; typedef const T* const_pointer; typedef T& reference; typedef const T& const_reference; typedef T value_type; template<typename X> struct rebind { typedef MyPoolAlloc<X> other; }; MyPoolAlloc() throw() { printf("-------Alloc--CONSTRUCTOR--------%08x %32s\n", this, typeid(T).name()); } MyPoolAlloc(const MyPoolAlloc&) throw() { printf(" Copy Constructor ---------------%08x %32s\n", this, typeid(T).name()); } template<typename X> MyPoolAlloc(const MyPoolAlloc<X>&) throw() { printf(" Construct T Alloc from X Alloc--%08x %32s %32s\n", this, typeid(T).name(), typeid(X).name()); } ~MyPoolAlloc() throw() { printf(" Destructor ---------------------%08x %32s\n", this, typeid(T).name()); }; pointer address(reference __x) const { return &__x; } const_pointer address(const_reference __x) const { return &__x; } pointer allocate(size_type __n, const void * hint = 0) { if (__n != 1) perror("MyPoolAlloc::allocate: __n is not 1.\n"); if (NULL == pMyPool) { pMyPool = new MyPool(); printf("======>Creating a new pool object.\n"); } return reinterpret_cast<T*>(pMyPool->GetNext()); } //__p is not permitted to be a null pointer void deallocate(pointer __p, size_type __n) { pMyPool->Free(reinterpret_cast<void *>(__p)); } size_type max_size() const throw() { return size_t(-1) / sizeof(T); } void construct(pointer __p, const T& __val) { printf("+++++++ %08x %s.\n", __p, typeid(T).name()); ::new(__p) T(__val); } void destroy(pointer __p) { printf("-+-+-+- %08x.\n", __p); __p->~T(); } }; template<typename T> inline bool operator==(const MyPoolAlloc<T>&, const MyPoolAlloc<T>&) { return true; } template<typename T> inline bool operator!=(const MyPoolAlloc<T>&, const MyPoolAlloc<T>&) { return false; } template<typename T> MyPool* MyPoolAlloc<T>::pMyPool = NULL; int main(int argc, char *argv[]) { std::map<int, int, std::less<int>, MyPoolAlloc<std::pair<const int,int> > > m; //random insertions in the map m.insert(std::pair<int,int>(1,2)); m[5] = 7; m[8] = 11; printf("======>End of map insertions.\n"); return 0; } Here is the output of this program: -------Alloc--CONSTRUCTOR--------bffcdaa6 St4pairIKiiE Construct T Alloc from X Alloc--bffcda77 St13_Rb_tree_nodeISt4pairIKiiEE St4pairIKiiE Copy Constructor ---------------bffcdad8 St13_Rb_tree_nodeISt4pairIKiiEE Destructor ---------------------bffcda77 St13_Rb_tree_nodeISt4pairIKiiEE Destructor ---------------------bffcdaa6 St4pairIKiiE ======Creating a new pool object. Construct T Alloc from X Alloc--bffcd9df St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE +++++++ 0985d028 St4pairIKiiE. Destructor ---------------------bffcd9df St4pairIKiiE Construct T Alloc from X Alloc--bffcd95f St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE +++++++ 0985d048 St4pairIKiiE. Destructor ---------------------bffcd95f St4pairIKiiE Construct T Alloc from X Alloc--bffcd95f St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE +++++++ 0985d068 St4pairIKiiE. Destructor ---------------------bffcd95f St4pairIKiiE ======End of map insertions. Construct T Alloc from X Alloc--bffcda23 St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE -+-+-+- 0985d068. Destructor ---------------------bffcda23 St4pairIKiiE Construct T Alloc from X Alloc--bffcda43 St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE -+-+-+- 0985d048. Destructor ---------------------bffcda43 St4pairIKiiE Construct T Alloc from X Alloc--bffcda43 St4pairIKiiE St13_Rb_tree_nodeISt4pairIKiiEE -+-+-+- 0985d028. Destructor ---------------------bffcda43 St4pairIKiiE Destructor ---------------------bffcdad8 St13_Rb_tree_nodeISt4pairIKiiEE Last two columns of the output show that an allocator for std::pair<const int, int> is constructed everytime there is a insertion into the map. Why is this necessary? Is there a way to suppress this? Thanks! Edit: This code tested on x86 machine with g++ version 4.1.2. If you wish to run it on a 64-bit machine, you'll have to change at least the line return malloc(24). Changing to return malloc(48) should work.

    Read the article

  • "Temporary object" warning - is it me or the compiler?

    - by Roddy
    The following snippet gives the warning: [C++ Warning] foo.cpp(70): W8030 Temporary used for parameter '_Val' in call to 'std::vector<Base *,std::allocator<Base *> >::push_back(Base * const &)' .. on the indicated line. class Base { }; class Derived: public Base { public: Derived() // << warning disappears if constructor is removed! { }; }; std::vector<Base*> list1; list1.push_back(new Base); list1.push_back(new Derived); // << Warning on this line! Compiler is Codegear C++Builder 2007. Oddly, if the constructor for Derived is deleted, the warning goes away... Is it me or the compiler?

    Read the article

  • A follow up on type coercion in C++, as it may be construed by type conversion

    - by David
    This is a follow up to my previous question. Consider that I write a function with the following prototype: int a_function(Foo val); Where foo is believed to be a type defined unsigned int. This is unfortunately not verifiable for lack of documentation. So, someone comes along and uses a_function, but calls it with an unsigned int as an argument. Here the story takes a turn. Foo turns out to actually be a class, which can take an unsigned int as a single argument of unsigned int in an explicit constructor. Is it a standard and reliable behavior for the compiler to render the function call by doing a type conversion on the argument. I.e. is the compiler supposed to recognize the mismatch and insert the constructor? Or should I get a compile time error reporting the type mismatch.

    Read the article

  • CDI SessionScoped Bean results in two instances in same session

    - by Ryan
    I've got two instances of a SessionScoped CDI bean for the same session. I was under the impression that there would be one instance generated for me by CDI, but it generated two. Am I misunderstanding how CDI works, or did I find a bug? Here is the bean code: package org.mycompany.myproject.session; import java.io.Serializable; import javax.enterprise.context.SessionScoped; import javax.faces.context.FacesContext; import javax.inject.Named; import javax.servlet.http.HttpSession; @Named @SessionScoped public class MyBean implements Serializable { private String myField = null; public MyBean() { System.out.println("MyBean constructor called"); FacesContext fc = FacesContext.getCurrentInstance(); HttpSession session = (HttpSession)fc.getExternalContext().getSession(false); String sessionId = session.getId(); System.out.println("Session ID: " + sessionId); } public String getMyField() { return myField; } public void setMyField(String myField) { this.myField = myField; } } Here is the Facelet code: <?xml version='1.0' encoding='UTF-8' ?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xmlns:h="http://java.sun.com/jsf/html" xmlns:f="http://java.sun.com/jsf/core"> <f:view contentType="text/html" encoding="UTF-8"> <h:head> <title>Test</title> </h:head> <h:body> <h:form id="form"> <h:inputText value="#{myBean.myField}"/> <h:commandButton value="Submit"/> </h:form> </h:body> </f:view> </html> Here is the output from deployment and navigating to page: INFO: Loading application org.mycompany_myproject_war_1.0-SNAPSHOT at /myproject INFO: org.mycompany_myproject_war_1.0-SNAPSHOT was successfully deployed in 8,237 milliseconds. INFO: MyBean constructor called INFO: Session ID: 175355b0e10fe1d0778238bf4634 INFO: MyBean constructor called INFO: Session ID: 175355b0e10fe1d0778238bf4634 Using GlassFish 3.0.1

    Read the article

  • Android Frame by Frame Animation problem on elements in a CursorAdapter

    - by Pandalover
    I am having trouble applying an animation to a View. I am trying to load the animation from inside the constructor of a CursorAdapter, so I can set it later assign it to certain children in the list. In the constructor I have : shineAnimation = AnimationUtils.loadAnimation(ctx, R.anim.news_list_item_shine); the animation is in my res/anim dir <?xml version="1.0" encoding="utf-8"?> <animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="true"> <item android:drawable="@drawable/shine1" android:duration="200" /> <item android:drawable="@drawable/shine2" android:duration="200" /> <item android:drawable="@drawable/shine3" android:duration="200" /> <item android:drawable="@drawable/shine4" android:duration="200" /> <item android:drawable="@drawable/shine5" android:duration="200" /> </animation-list> I'm getting an exception : Unknown animation name: animation-list Help would be much appreciated Thanks S

    Read the article

  • Passing Reference types by value in C#

    - by Ajit
    I want to pass a reference type by value to a method in C#. Is there a way to do it. In C++, I could always rely on the copy constructor to come into play if I wanted to pass by Value. Is there any way in C# except: 1. Explicitly creating a new object 2. Implementing IClonable and then calling Clone method. Here's a small example: Let's take a class A in C++ which implements a copy constructor. A method func1(Class a), I can call it by saying func1(objA) (Automatically creates a copy) Does anything similar exist in C#. By the way, I'm using Visual Studio 2005.

    Read the article

  • Twitter's Bootstrap 2.x popover callback can't focus on element

    - by mozgras
    I've modified bootstrap's popover function to include a callback which works great. But in the callback I cannot programmatically focus on the first form field. Strange, because I can manipulate other elements in the callback function as well as focus on the element at other points. Here's the code to add a callback which I got from another SO question (http://stackoverflow.com/a/14727204/1596547): var tmp = $.fn.popover.Constructor.prototype.show; $.fn.popover.Constructor.prototype.show = function () { tmp.call(this); if (this.options.callback) { this.options.callback(); } } Here's the popover code: $('#a-editor-btn').popover({ html: true, placement: 'bottom', callback: function(){ $('#a-form-point').focus(); //nothing happens console.log('hello'); // works . . }, content: $('#a-form').html() }).parent().delegate('button#insert-point-btn', 'click', function() { insertPoint(); }).delegate('.a-form','keypress', function(e) { if ( e.which == 13 ) { insertPoint(); } });

    Read the article

  • JavaScript: How to create a new instance of a class without using the new keyword?

    - by Alessandro Vernet
    I think the following code will make the question clear. // My class var Class = function() { console.log("Constructor"); }; Class.prototype = { method: function() { console.log("Method");} } // Creating an instance with new var object1 = new Class(); object1.method(); console.log("New returned", object1); // How to write a factory which can't use the new keyword? function factory(clazz) { // Assume this function can't see "Class", but only sees its parameter "clazz". return clazz.call(); // Calls the constructor, but no new object is created return clazz.new(); // Doesn't work because there is new() method }; var object2 = factory(Class); object2.method(); console.log("Factory returned", object2);

    Read the article

  • C++ addition overload ambiguity

    - by Nate
    I am coming up against a vexing conundrum in my code base. I can't quite tell why my code generates this error, but (for example) std::string does not. class String { public: String(const char*str); friend String operator+ ( const String& lval, const char *rval ); friend String operator+ ( const char *lval, const String& rval ); String operator+ ( const String& rval ); }; The implementation of these is easy enough to imagine on your own. My driver program contains the following: String result, lval("left side "), rval("of string"); char lv[] = "right side ", rv[] = "of string"; result = lv + rval; printf(result); result = (lval + rv); printf(result); Which generates the following error in gcc 4.1.2: driver.cpp:25: error: ISO C++ says that these are ambiguous, even though the worst conversion for the first is better than the worst conversion for the second: String.h:22: note: candidate 1: String operator+(const String&, const char*) String.h:24: note: candidate 2: String String::operator+(const String&) So far so good, right? Sadly, my String(const char *str) constructor is so handy to have as an implicit constructor, that using the explicit keyword to solve this would just cause a different pile of problems. Moreover... std::string doesn't have to resort to this, and I can't figure out why. For example, in basic_string.h, they are declared as follows: template<typename _CharT, typename _Traits, typename _Alloc> basic_string<_CharT, _Traits, _Alloc> operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs) template<typename _CharT, typename _Traits, typename _Alloc> basic_string<_CharT,_Traits,_Alloc> operator+(const _CharT* __lhs, const basic_string<_CharT,_Traits,_Alloc>& __rhs); and so on. The basic_string constructor is not declared explicit. How does this not cause the same error I'm getting, and how can I achieve the same behavior??

    Read the article

  • C++ cast syntax styles

    - by palm3D
    A question related to Regular cast vs. static_cast vs. dynamic_cast: What cast syntax style do you prefer in C++? C-style cast syntax: (int)foo C++-style cast syntax: static_cast<int>(foo) constructor syntax: int(foo) They may not translate to exactly the same instructions (do they?) but their effect should be the same (right?). If you're just casting between the built-in numeric types, I find C++-style cast syntax too verbose. As a former Java coder I tend to use C-style cast syntax instead, but my local C++ guru insists on using constructor syntax. What do you think?

    Read the article

  • Can PHP Perform Magic Instantiation?

    - by Aiden Bell
    Despite PHP being a pretty poor language and ad-hoc set of libraries ... of which the mix of functions and objects, random argument orders and generally ill-thought out semantics mean constant WTF moments.... ... I will admit, it is quite fun to program in and is fairly ubiquitous. (waiting for Server-side JavaScript to flesh out though) question: Given a class class RandomName extends CommonAppBase {} is there any way to automatically create an instance of any class extending CommonAppBase without explicitly using new? As a rule there will only be one class definition per PHP file. And appending new RandomName() to the end of all files is something I would like to eliminate. The extending class has no constructor; only CommonAppBase's constructor is called. Strange question, but would be nice if anyone knows a solution. Thanks in advance, Aiden (btw, my PHP version is 5.3.2) Please state version restrictions with any answer.

    Read the article

< Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >