We're trying to overload the delete[] operator with specific arguments. Which is the right way to call it? We use the GNU compiler and obtain compiler errors with all of these samples:
#include<iostream>
using namespace std;
typedef unsigned int P;
[Code]....
I'm doing a refresher for C++ and have gotten to operator overloading. I'm trying to perform an operator overload with the insertion (<<) operator, but I have encountered a problem.
Here's my class [In a header file "Shinigami.h"]
#include<string>
namespace K{
class Quincy;
class Shinigami{
friend std::ostream& operator<<(std::ostream&, const Shinigami&);
[Code] .....
If the operator function is a friend of the 'Shinigami' class, why doesn't it recognize any of it's private members? I need it to be in this file because I'm doing a bit of association with the 'Quincy' class.
I thought it was the namespace, but I included that.
Here's my question. I'm coding a basic Linked List class (for the purpose of understanding and having fun, I know about STL), LList.
I have overloaded the [] operator so it returns the data of the index-th node in the list, for example, if I code
LList x;
....
cout<<x[5];
it prints the data of the 5th node in the list (for fun I decided to index from 1 to infinity).
My question: Now I want to be able to assign the value to the index-th node data, using [] and =, for example, I want to be able to write:
LList x;
.....
x[5] = 121;
How can I do that?
How would i be able to overload a multiplication operator that if, in the main example(0, 5, 0) * example (0, 5, 0) is given, it gives me 25?
View 1 Replies View RelatedSay I have a class that requires dynamic allocation to implement a few of the operators. Take "+" for example; I need to create a new object to hold the sum of the two parameters whose size is not known at compile time.
I'm pretty sure the standard way to indicate a failure inside the overloading function would be to throw an exception. However I am currently involved in an embedded(ish) project where the spec. says no exceptions are to be used.
I think I have 2 options:
1. Return an "invalid" object (with a flag indicating an error has occurred) and check for this after each operation.
a = b + c
if (a.err)
// handle error
or
2. To forsake operator overloading entirely and think up a new way of doing things where all functions that involve dynamic allocation can return error codes. but this seems rather terrible too as I may end up with something like:
objA a
if (add(&a, b, c) == -1) // assuming b and c are initialized before this snippet starts
// handle error
Is there a number 3 that I haven't thought of? It seems that not allowing exceptions is fairly common even in the non-embedded world [URL] so how is this normally done? or is operator overloading usually avoided when exceptions are not allowed?
I'm trying to come up with the union of two Vector ADT bags, so I have to overload the '+' operator, but I'm getting a bunch of error messages saying:
VectorBag.cpp: In instantiation of ‘VectorBag<ItemType> VectorBag<ItemType>::operator+(VectorBag<ItemType>) [with ItemType = int]’:
proj2.cpp:161:42: required from here
VectorBag.cpp:81:24: error: no match for ‘operator[]’ (operand types are ‘VectorBag<int>’ and ‘int’)
newBag.add(anotherBag[i]);
^
Here is the function to overload the operator:
template<class ItemType>
VectorBag<ItemType>
VectorBag<ItemType>::operator+(VectorBag<ItemType> anotherBag) {
VectorBag<ItemType> newBag;
for (int i = 0; i < anotherBag.getCurrentSize(); i++)
newBag.add(anotherBag[i]);
}
The add() function is pre-defined by me somewhere else in the code. It basically does push_back().
I want to overload prefix and postfix increment(++) operators with friend function. I also have to use the constructors for this. How can I do this? in C++
View 4 Replies View Relatedi am doing some practice problems and i can't seem to figure out how to do this. basically we have a students number of test scores, then the name followed by the scores they have in a text file. Then we have to make a class with a constructor, copy constructor, destructor, and overload the = operator and the input and output operator. Are we suppose to call the text file in the input overload operator?
Here is what i have so far.
This is my header file.
#ifndef STUDENTTESTSCORES_H
#define STUDENTTESTSCORES_H
#include <string>
#include <iostream>
using namespace std;
class StudentTestScores{
private:
string studentName;
[Code]...
i am 100% sure the overloading the input is wrong
here is the implementation of the constructor copy constructor and desctructor
#include <iostream>
#include "StudentTestScores.h"
using namespace std;
StudentTestScores::StudentTestScores(string name = "", int numScores = 0)
{
studentName = name;
numTestScores = numScores;
if (numScores <= 0)
testScores = NULL;
else
[Code]...
and here is the notepad file
3
Justin Bieber491.469.184.681.081.5
Miley Cyrus380.080.090.083.3
Kim K490.575.661.481.677.2
The program is suppose to use all the information and read from the notepad and output the exact things as the notepad file
struct Node {
int entry;
Node *next;
Node(); //1
Node(int item, Node *link = NULL); //2
[Code] .....
Implement: 1 2 3 4 5
and overload operator <<, >>, =
/*using GENERIC_COMMAND* A; as volatile generates error. but here i have to use union object as volatile i.e. volatile GENERIC_COMMAND* A; */
#include <iostream>
using namespace std;
typedef unsigned int uint32_t;
typedef unsigned long long uint64_t;
union GENERIC_COMMAND {
[Code] .....
Consider the class specification below. Write the prototype (i.e. header) of a member function to overload the insertion operator (i.e. <<). The << operator is to output the data members of an instance of class StudentTestScores into an output stream. Your definition should allow for chaining of output operations (e.g. cout << x << y; where x and y are of type StduentTestScires).
#include <string>
using namespace std;
class StudentTestScores{
private:
string studentName;
float *testScores; // used to point to an array of test scores
int numTestScores; // number of test scores
[code]....
I have a basic vector/point class where I've overloaded a bunch of arithmetical operators:
Code:
#pragma once
class point {
public:
point() {
}
point(float p_x, float p_y, float p_z) : x(p_x), y(p_y), z(p_z)
[Code] ...
I can use it fine like
Code:
point p(50,50,50);
point q(50,50,50);
point t = p * q + q;
However when I put this point type into a struct and try to access the members after passing it through by const reference:
Code:
struct sextic {
point a,b,c,d,e,f,g;
};
inline static sextic sexticDifference(const sextic &p_sextic1, c
[Code] ....
This gives me an "operator not defined" error for compilation.
Some codes to delete a text in a specific line in a text file.
Example:
This is line 1
This is line 2
this is line 3
Removing line 2,
This is line 1
This is line 3
//////////////////
We can't use the std::vector, std::map and std::lists implementations.
std::realloc doesn't call the destructor automatically.
If it is theoretically possible, we'll consider it and write lines similar to it, which should remain commented until something similar is possible.
int main(){
#define START 1000000000
#define END 10
unsigned int * array=new unsigned int[START];
delete[START-END]array;//Our suggestion to shrink the array
delete[]array;//Delete the array
return 0;
}
Suppose I have the following structure
struct b
{
char fullname[100];
char title[100];
bopname
};
and i declare a pointer to the struct as follows
b* bp;
and at runtime,
bp = new b[5];
In the end, is the statement delete[ ] bp enough to release the dynamically allocated memory. Or do i need to separately delete bp[0],bp[1]...
Does delete[ ] bp indicate that the array[ ] pointed by bp has to be deleted?? [I am confused as to how this happens, since the pointer only points at the 1st struct address]
I am not getting the real concept of delete operator. If it deallocates the memory, then why i am getting such output..!!
int main() {
int *a , b=5;
a = & b;
cout << *a << endl;
delete a;
cout << *a;
getch();
return 0;
}
Output:
5
5
int main() {
int vnum = 0;
VEHICLE *vehiptr;
VEHICLE *dptr;
cout<<"Please enter the number of vehicle: ";
cin>>vnum;
vehiptr = new VEHICLE[vnum];
[Code] .....
How can I declare global 'delete' operation multiple times? Like, I've an implementation of global 'delete' operation in a file 'x' but I want a different behavior in file 'y'. However, if I override it again in file 'y' I get multiple definition error.
View 3 Replies View RelatedHow do I make a specific character show up a specific amount of times?
Like I am generating a random number then I need to make "|" show up that many times on the screen.
I have to manage a Clinic. I need to delete a booking (for example, if John said he's coming on March 22nd at 15:30 but then he say he's not going to come, I have to delete that booking so another person can use it).
idSearched: the id of the person that is not going to come. I have a lot of specialties and each one has a list. So I ask for the speciality to delete the node (the node contains John's booking). If I don't find it, I return (-1). searchSpecByID return a pointer to the list where the speciality is. So head will point to the first node of the list. In nodeToDelete I have the node I want to delete.
The program detects OK when is the first in the list and when not, but it doesn't delete the node.
Code:
typedef struct bookingList{
tSpecialty specialty;
struct nodo* intro;
} tList;
[Code].....
I am a beginner, got confused about:
template<typename T> int compare(T &a,T &b);
int compare(const char *a,const char *b);
char ch_arr1[6]="world",ch_arr2[6]="hello";
compare(ch_arr1,ch_arr2);
After running the code above,we got to know the non-template function is called. What I know is that the array arguments ch_arr1,ch_arr2 will not be converted to char * because the parameters are references in the template functions.
ch_arr1,ch_arr2 need to be converted to const char * if compare(const char *a,const char *b) were called.
I just wanna know what exactly happened behind that? and why?
Is it possible to overload a variable in a derived class? Example:
struct Circle
{
int radius() const { return r; }
private:
int r;
}
struct Smiley : Circle
{
// inherits the function int radius() const, but doesn't return Smiley::r
private:
int r;
}
I'm still pretty new to classes so what am i doing in this code that is wrong.
#include <iostream>
#include <stdlib.h>
#include <time.h>
#include <string>
using namespace std;
class BunnyInfo{
[Code]...
I want to be able to do
someFunction(MyObject)
rather than
someFunction(MyObject.getWhatIWant())
I know I can do &MyObject, MyObject() and MyObject[0] by overloading operators but is it possible with just plain old MyObject?
this is assuming that I have no access to someFunction(), i.e, it cannot be modified.
Firstly, is it legal to overload a template function in a class? This is what I did
class FILE_txt
{
public:
FILE_txt(const char* );
[Code]....
I want to overload pure virtual function from 3rd party SDK class to put my debug messages like that:
errorStatus aXsaction(){printf(_T("
abort transaction"));transactionManager->abortTransaction();}
#define transactionManager->abortTransaction() aXsaction()
But compiler complains on the minus sign:
error C2008: '-' : unexpected in macro definition
Is it possible to trick the compiler?