error C2995: 'foo<l+r> operator *(const foo<s> &,const foo<r> &)' : function template has already been defined
see declaration of 'operator *'
see reference to class template instantiation 'foo<s>' being compiled
with
[
s=4
]
If I change the operator to return a foo<s> it does compile (but that's not the behaviour I need).
if I move the operator to outside the class (removing the 'friend') it does compile and behaves how I need, but I can't access non-public members so I can't write the implementation correctly.
I am doing C++ data structures exercises, and I am still learning some of the more basic concepts. I have a parent class:
template<class T> class linkedListType { public: protected: int count; nodeType<T> *first; nodeType<T> *last; private: };
Derived class:
#include "linkedListType.h" template<class T> class orderedLinkedList: public linkedListType<T> { public: void mergeList(orderedLinkedList<T> &list1, orderedLinkedList<t> &list2) { first = list1.first; ... } private: };
There is more code in my mergeList() function, but I included the line that is giving me problems. The error that my CodeBlocks compiler is giving me is that 'first' was not declared in this scope.
Strangely enough, if I change it to this->first, the error disappears.
1. Why does it not recognise 'first'? 2. Why would this->first work at all? Is the 'this' object a smart pointer?
I have a little problem with template classes and their specialization. Here is a short example:
template <typename T> struct A{ // some typedefs
[Code]....
The above example is not compiling, because of the assignment of the const static double. Double needs a constructor, but that doesn't work (or seems not to work) with static.
I'm not sure, if it works at all in C++ that way. All I want is a template struct with some typedefs and a constant which is different for different specializations. Don't think it has to be static, but that would be better style, wouldn't it?
A static function can be called in relation to a particular object by a statement such as the following:
aBox.Afunction(10);
The function has no access to the non-static members of aBox. The same function could also be called without reference to an object. In this case, the statement would be:
CBox::Afunction(10);
where CBox is the class name. Using the class name and the scope resolution operator tells the compiler to which class Afunction() belongs."
I've been writing my own implementation of quicksort in a .h file. I've gotten to the point where I think I'm done with the algorithm, so now I'm trying to make it so that if someone includes "quicksort.h", they will only have access to certain functions in the file. Kind of like public and private functions in a class, but without the "class" part of it. How do you do that?
I have read the book over and over and I thought I understand "CLASS". But when I applied it and write the code the compiler tells me that there is a compiling error.
1. I have this method addProduct(Product* pProduct) in a Class called ProductRack, the code is in ProductRack.cpp file. The declaration of the Class methods and private variables are in ProductRack.h header file.
2. But when I call a method in the DeliveryCHute Class from the ProductRack Class I get a compiler errors which are these:
A.IntelliSense: a nonstatic member reference must be relative to a specific object B.error C2352: 'Project1::DeliveryChute::insertProduct' : illegal call of non-static member function
And this is causing the error:
if (Project1::DeliveryChute::insertProduct(pProduct) == false)
//THIS IS JUST ONE METHOD INSIDE ProductRack.cpp bool Project1::ProductRack::addProduct(Product* pProduct) { // Todo : Implementing if (Project1::DeliveryChute::insertProduct(pProduct) == false) return true;
I need to run a public domain code in Molecular Dynamics. I have a Knoppix 7.2 system with Geany and gcc 4.7.2-5 and g++ 4:4.7.2-1 .
I need to compile this code and create a binary but can't.
The output:
gcc -o md md.c /tmp/ccODg4eA.o: In function `compute': md.c:(.text+0x718): undefined reference to `sin' md.c:(.text+0x72a): undefined reference to `pow' md.c:(.text+0x794): undefined reference to `sin' /tmp/ccODg4eA.o: In function `dist': md.c:(.text+0x8f9): undefined reference to `sqrt' collect2: error: ld returned 1 exit status
note that since this is a Public Domain code, I have not altered it. The main code:
#include <stdlib.h> #include <stdio.h> #include <time.h> #include <math.h> #include <string.h> int main ( int argc, char *argv[] ); void compute ( int np, int nd, double pos[], double vel[], double mass, double f[], double *pot, double *kin );
I've finally managed to do something with the combo box but knock down one wall it's like there's another one five inches behind it. What I mean is I've figured out how to add items to the combo box and have them show images in my picture box. Only problem is when I went to debug my combo box kept looping it's options over and over and over.
Private Sub xpmaleskincolorselect.Items.Add("Tone1"); malesprite.Image = My.Resources.Resources.XP_Female_clear; xpmaleskincolorselect.Items.Add("Tone2"); malesprite.Image = My.Resources.Resources.XP_Male_tan; xpmaleskincolorselect.Items.Add("Tone3"); malesprite.Image = My.Resources.Resources.XP_Male_dark; End Sub
The subs, I know they aren't right but its just to show I know where they go. Anyway using Private Sub and End sub doesn't seem to work. I'll type them in then at the error box at the bottom it'll say that it doesn't exist in the namespace. Same thing happened when I tried to add public class beforehand to see if that would work same thing about the name space.
I'm trying to create a public and static field in a class called ResourceManager. But when trying to access the field even from inside the class it wont work. I'm getting this error message:
Error 1 error LNK2001: unresolved external symbol "public: static int ResourceManager::num" (?num@ResourceManager@@2HA)
Here's my code: ResourceManager.h
Code:
class ResourceManager { public: static int num; static void loadContent();
if we don't provide the acces modifiers for base class and we need to manipulate the private data of base class in derived class. Is there anyway to acces the private data members? Here's a coding example
class A { private : int a; }; class B : public class A { public : void displayA() { cout<<a<<endl; } };
how i can acces the a of base class A in derived class B without acces modifiers.
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 am just trying to get a code going for a mock test and to get use to the getline and IF operations, but it seems I have ran into an issue[URL] is a link to the code I have written, and I can use getline to give a value to my variable, but it seems like it gets lost once I try to use the IF function. Am I not using the right variable type?
class DataBase { // Change the connection path here to your own version of the database public SqlConnection con = new SqlConnection(@"Data Source=(LocalDB)v11.0;AttachDbFilename=|DataDirectory|UberDatabase.mdf;Integrated Security=True;"); public DataBase() { } }
And in the same namespace as this class I have a form that calls it like so:
DataBase dBase = new DataBase(); SqlCommand trythis = new SqlCommand("Register", dBase.con);
However, I'm getting the field initializer error on dBase.con. I'm not sure why, but when I call the database from another file (program.cs) it works fine this way.
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;
where 'g()' returns an object of the element type. However, the compiler is claiming, no matter how I write a call to the overload, the original template is selected and/or the overload is invalid, depending on the various ways I attempt to write said overload.
I need to run some operation if a key from keyboard is pressed. so I go with
Code: c=getchar();
to get it read. yet the user could press a key anytime; so I'd need some if-loop. no plans on how it'd look like though...I suppose something like this below wouldn't work right?
