/*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] .....
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.
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.
I made a simple binary tree then decide to try out threads too. I got the following error:
call of an object of a class type without appropriate operator or conversion
Code:
#include "Tree.h"
#include <iostream>
#include <thread>
void main(void){
[Code] ....
I am having a hard time figuring out why the error exists. I tried adding the new operator but that did not work.
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?
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 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 <<, >>, =
I have code here that uses assignment operators that doesn't return by reference and it still works. So why does my book say you need to return by reference?
Here is a quote from my book:
The return type of operator= is a reference to the invoking object, so as to allow chained
assignments a=b=c.
The code below is from my book. I simply removed '&', in the original code that has assignment operators return by reference, from IntCell & operator=. This way the assignment operator no longer returns a reference, and it still works.
#include <iostream>
using namespace std;
class IntCell {
public:
explicit IntCell( int initialValue = 0 )
{ storedValue = new int{ initialValue }; }
[Code] .....
I am wondering why return type for an assignment operator cant be a void or int? Cant I write assignment operator for student class like this as we do nothing with returned value?
Student {
char name[20];
int marks;
public:
student(char*name,int marks)
[code].....
The task is to use the assignment operator of a class, but change all the data except certain ones. For example, below we are to assign all Person data of 'other' except for 'name' and 'ID':
#include <iostream>
#include <string>
struct Person {
std::string name;
int ID, age, height, weight;
[Code] .....
Name = Bob
ID = 2047
Age = 38
Height = 183
Weight = 170
Name = Frank
ID = 5025
Age = 25
Height = 190
Weight = 205
Bob pretends to be Frank, but keeps his name and ID.
Name = Bob
ID = 2047
Age = 25
Height = 190
Weight = 205
But I think the way I did it is pretty lousy (note the wasted steps changing the name and ID only to revert them back? So the ideal solution should require no wasted steps, unlike the method above, and changes to what the exclusions should be should be in only one place (not two like above). Of course, we assume that Person shall have many, many data members (and constantly increasing), so that simply defining Person::operator= (const Person& other) to handle all data except for 'name' and 'ID' is out of the question.
How do i write main test program to test the copy constructor and assignment operator in this program...how do i know if its working as its suppose to?i just want to know about copy and assignment operator..i have figured out the test program for other things..Here my program :
ListType.h
#ifndef LISTTYPE_H
#define LISTTYPE_H
#include<iostream>
class ListType{
public:
ListType(size_t=10);
ListType(const ListType&);
[Code] ......
I've been working on some project and I got to wondering when you know you need to use a copy constructor and an assignment operator. Is there a rule of thumb? I know there is the Rule of Three, but is there something that tells you when you need those three?
View 4 Replies View RelatedBelow is exception proof approach of assignment operator shared by scott meyer. Is it safe to delete the raw pointer.
int *orig =m_p;
m_p=new int (*obj.m_p);
delete orig;
Class A
{..........}
Class B:
{....
private U& u;}
I need to write the copy constructor and assignment operator for Class B above. Copy would look something like this:
B::B(conts B& bo): u(bo.u){}
is this correct ... and how will the assignment operation look like??
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]....
Go to this link : [URL] .....
Actually I am not getting one thing in this code that why they only provide the declaration of Copy constructor and Assignment operator...??
how the operator overloaded methods called in C++?
Class String {
int len;
char *str;
public:
String(const char *str1="") {
len=strlen(str1);
str=new char[len+1];
strncpy(str,str1,len+1);
[code]....
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:
template<class dataType>
const myArray<dataType>& myArray<dataType>::operator=(const myArray<dataType>& rightArray) {
int i;
if(this != &rightArray) {
delete [] arrayPtr;
[Code] ....
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 am trying to create the assignment operator for a class that uses a pointer for it's private variable. The error is saying expected constructor, deconstructor, or type conversion before "operator. (which is the assignment operator. I have tried everything i could think of or find online and nothing has worked. below is the code for the assignment operator in the .h file and the .cpp file.
//Assignment constructor
indexList &operator=(const indexList <T> &rhs);
template <class T>
indexList<T>::indexList operator=(const indexList <T> &rhs) {
if(this != &rhs) {
numberOfElements = rhs.numberOfElements;
[Code]...
I am working on a double linked list and inside of my function to insert a node, I am getting an error of "Incompatible types in assignment". Here is my function code. Line 55 is where I am receiving the error.
Code:
45 struct lnode *ins_llist(char data[], struct llist *ll){
46 struct lnode *p, *q;
47
48 q = malloc(sizeof(struct lnode));
49 if ( q == NULL )
[Code]....
I am getting this error when compiling my program with quincy:
Error: I value required as left operand of assignment
The program is meant to calculate how much parking costs based on the amount of hours in a park and what type of vehicle it is. the error is coming from my function definitions which i have just started to add in.
Code:
float calcCarCost (char vehicletype, int time, float car)
{
if ((time > MINTIME) && (time <= 3))
calcCarCost =( CAR * time );
}
The error is on line 72 which is:
calcCarCost =( Car * time);
I should probably point out CAR is already defined as a constant with a numerical value given and time is previously asked to be input in when the program runs.
