main3.cpp: In member function ‘FooB& FooB::operator=(const FooC&)’: main3.cpp:46:44: error: expected ‘(’ before ‘other’ main3.cpp:46:49: error: no matching function for call to ‘Foo<C>::Foo(const FooC&)’ main3.cpp:46:49: note: candidates are: main3.cpp:19:2: note: Foo<T>::Foo() [with T = C] main3.cpp:19:2: note: candidate expects 0 arguments, 1 provided main3.cpp:16:25: note: Foo<C>::Foo(const Foo<C>&) main3.cpp:16:25: note: no known conversion for argument 1 from ‘const FooC’ to ‘const Foo<C>&’
I designed a class template to create unique arrays. I was able to successfully input data to and output data from my array objects, irrespective of the datatype. However, I can't for the life of me fathom why my overloaded assignment operator worked perfectly well only for integer datatype and not for double/string datatypes.
Here is the class definition:
template <class dataType> class myArray { public: void setArrayData();
[code]....
And here is the definition of the overloaded assignment operator:
And here is my main function that tests the operations on objects of the class:
int main(){ //object declarations myArray<double> list(5); //a single-parameter object declaration of class myArray myArray<double> myList(2,13); //a two-parameter object declaration of class myArray
[code]....
The problem I'm having starts from where the assignment operator is being tested: for double and string datatypes, the upper input/output section works fine, but the assignment section freezes the display until the program execution is manually terminated!
I can't provide a generic implementation of the << operator, it depends on the specific types of T. So how do I specialize the operator for a specific type T ?
I'm trying to implement a simple template array class, but when i came into the operator< i actually have to use a template :
my code is something like :
template<typename _Type, std::size_t _Size> class array { public :
[Code] ......
but i am having an error of shadows template param 'class _Type' is it w/ the name conflict between the array template parameter and the function template parameter ?
Error1error C2955: 'DoubleLinkedListInterface' : use of class template requires template argument listdoublelinkedlist.h10 Error2error C2244: 'DoubleLinkedList<T>::DoubleLinkedList' : unable to match function definition to an existing declaration doublelinkedlist.cpp7
Error3 .cpperror C2244: 'DoubleLinkedList<T>::~DoubleLinkedList' : unable to match function definition to an existing declaration 12
.h
#pragma once #include "DoubleLinkedListInterface.h" #include "Node.h" #include <iostream>
I what to implement to my Template operator * . There is <Template> Array which purpose is container like vector for classes. There is class Point, each object of contain two coordinate x and y.
So, 1. I wanna fill Array with objects from Point class 2. Multiply each objects from this vector to a factor 3. And print all this bunch of objects ()...
And pop -up helper tell that : Error: no suitable user defined conversion from "Point " to Array<Point> exist
Code: //array.h #ifndef Array_H #define Array_H template <class Type> //Remove the "=double" default parameter. class Array { protected: int m_size; Type* m_data; //m_data should be a pointer, since you want to allocate data to it
I have a generic template class with another template in one of its types. Now I want to specialize one of its methods for a particular (template) class, which leads to a compile error, however.
GCC ends with: :35:27: error: type/value mismatch at argument 2 in template parameter list for ‘template<class Type, template<class> class O> class Foo’ :35:27: error: expected a class template, got ‘Obj2<Type>’
What is wrong with the specialization? Can it even be achieved and how (if so)?
how I want the code to look. Only problem is it doesn't work (Line 11). I have some experience with templates but I'm not a pro.
Basically I want the "Channels<3>" to be a type that I can use to specify a Cable with similar to vector<float/int> it would be Cable<Channels<2 or 3>>.
What have I messed up with the syntax?
#include <iostream> #include <vector> using namespace std;
/** This class build the singleton design pattern. Here you have full control over construction and deconstruction of the object. */ template<class T> class Singleton
[Code]....
I am getting error at the assertion points when i call to the class as follows:
I am trying to pass a class as a type to a template class. This class's constructor needs an argument but I cannot find the correct syntax. Is it possible?
Here is an example of what I described above. I did not compiled it, it is for illustrative purpose only. And of course argument val of the myData constructor would be doing something more useful than simply initializing an int....
template <class T> class templateClass { templateClass() {};
[Code]....
My real code would only compile is I add the myData constructor:
myData () {};
and gdb confirmed that it is this constructor that get called, even with dummy(4).
Is it usual to rely completly on the new operator in constructors/copy constructors. What if new trows an exception? The application ends and that's it? The new operator can be placed where it can't be catch like in constructor initialization list. What kind of practice I should adopt when using "new" in those cases?
The sample code below is taken from here... [URL] ....
class MemoryBlock { public:
// Simple constructor that initializes the resource. explicit MemoryBlock(size_t length) : _length(length) , _data(new int[length])
So i am having troubles with operator overloading in inherited class. Basically, it doesnt work. Consider this:
Code:
class A { public: A() { x=0; z= new int;
[Code] ....
Some how the copy constructor of a is improperly executed - the pointer is copied over, not re-created. As a result, the destructors crashes due to double-free.
*/ B bb = b; //doesnt work B bbb(b); //doesnt work B bbbb(b, 0); //works }
Above code shows the problem well. The "official" copy-constructor wont work - it copies over the pointer directly, and doesnt create a new one as it should. However, if i provide my own pseudo-copy-constructor that works. But ofcourse it's just a cheap work around - and wont actually work in real code (STL).
I have an abstract class called Mbase and from it derived two classes: Sparse and Dense. Now I have an array in which its elements can be either Sparse or Dense. So, I delcared the array to have pointers to Mbase class. For example:
PHP Code: Mbase** A; Sparse* A1 = new Sparse; Dense* A2 = new Dense; A[1] = dynamic_cast<Mbase*>(A1); A[2] = dynamic_cast<Mbase*>(A2);
Now, I have operator + defined in Sparse and Dense. but when I do
PHP Code:
A[1]+A[2]
I get that operator + is not defined for Mbase class. So, I tried to define it in the Mbase class
However, the last code does not compile complaining that it cannot declare a class of type abstract in Mbase operator +(Mbase A). I think this is because I am returning Mbase instance.
std::cout << "Hello C++ programmers!" << std::endl;
I am trying to create a LinkedList (and then, an ADT stack; // yes, I cannot use the STL stack because the teacher won't let me), and I am getting some weird error when I create a ListNode and declare LinkedList (which has the ListNodes!) a friend of it.
I have tried forward-declaring LinkedList in the ListNode.h file, but I get this error:
error: 'ListNode' does not name a type
Are there any other possible solutions to this problem; // without having to resort to crazy stuff like having a .h file #include a .cpp file, or even declaring and defining ALL OF MY CODE in the .h files???
Below is simplified code consists of two classes, namely Parent and Child.
Child is inherited from Parent.
All member functions of class Parent are declared virtual, and they have been overridden in the class Child.
Code 1:
#include <cstdlib> #include <iostream> using namespace std; #define QUANTITY 5 class Parent {
[Code] ....
The output of the code:
Child::showID() -- ID is 1804289383 Child::showID() -- ID is 846930886 Child::showID() -- ID is 1681692777 Child::showID() -- ID is 1714636915 Child::showID() -- ID is 1957747793
Parent::operator=() invoked.
Child::showID() -- ID is 1804289383 Child::showID() -- ID is 846930886 Child::showID() -- ID is 1714636915 Child::showID() -- ID is 1714636915 Child::showID() -- ID is 1957747793
Question:
Why is Parent::operator= invoked instead of Child::operator= ..?
Isn't it already declared virtual and hence would be overridden..?
I need to invoke Child::operator= instead. How to achieve this?
I have this class templates And This UML.I have to write this function +operator=(source: Array<ElemType, SIZE>): Array<ElemType, SIZE> but I do not know how to start the declaration / or start the function. I have to return a template but I do not know how to do it,