Question

I am working on this project just trying to keep up my c++ knowledge. Anyways, I am getting many, many errors when i try to implement an operator overload. Not sure why.

#include "students.h"
#include <iostream>
#include "Quack.h"

using namespace std;

void main()
{


quack* classmates = new quack;

classmates->pushFront(students("corey", "9081923456", 4.0));

cout << "\noriginal data set -- " << *students;

and this is where i am getting the errors with the operator. Oddly enough if i comment out the overloaded operator and leave it in students.cpp it compiles find.

#ifndef STUDENTS_H
#define STUDENTS_H
#include <iostream>

class students
{
      // causing errors
friend ostream& operator << (ostream& out,const students& student);

public:
students();
students(char * name, char* oitId, float gpa);
students(const students& student); // copy constructor;
 ~students();
const students& operator=(const students& student);

void getName(char* name) const;
void getoitId(char* oitId) const;
float getGpa(void) const;

void setName(char* name);
void setoitId(char* oitId);
void setGpa(float gpa);


private:
char*    name;
char*    oitId;
float    gpa;

};

#endif

}

and, causes errors alo. But not by itself..

#include "students.h"
#include <iostream>
#include <iomanip>

using namespace std;
#pragma warning(disable:4996)       

private:
char* name;
char* oitId;
float gpa;

students::students(): name(NULL), oitId(NULL), gpa(0)
{
}


students::students(char *name, char *oitId, float gpa): name(NULL), oitId(NULL), gpa(0)
{
setName(name);
setoitId(oitId);

}

students::~students()
{

if(name)
delete[] name;
if(oitId)
delete[] oitId;

}




const students& students::operator=(const students& student)
{

//if it is a self copy, don't do anything
if(this == &student)
    return *this;
//make current object *this a copy of the passed in student
else
{
    setName(student.name);
    setoitId(student.oitId);
    //setGpa(student.gpa);
    return *this;
}

}


void students::setName(char *name)
{

//release the exisisting memory if there is any
if(this->name)
delete [] this->name;

//set new name
this->name = new char[strlen(name)+1];
strcpy(this->name, name);

}

void students::setoitId(char *oitId)
{

if(this->oitId)
delete [] this->oitId;

//set new Id
this->oitId = new char[strlen(oitId)+1];
strcpy(this->oitId, oitId);

}

ostream& operator<< (ostream& out, const students& student)
{

//out << setw(20) << student.name
    //<< setw(15) << student.pccId
    //<< setw(8) << fixed << setprecision(2) << student.gpa;
return out;
}

here is the errors i get

syntax error : missing ‘;’ before ‘&’
: error C2433: ‘ostream’ : ‘friend’ not permitted on data declarations
error C4430: missing type specifier – int assumed. Note: C++ does not support default-int
error C2061: syntax error : identifier ‘ostream’
error C4430: missing type specifier – int assumed. Note: C++ does not support default-int
error C2805: binary ‘operator <<‘ has too few parameters
1>Generating Code…
1>Compiling…
1>students.cpp

my eyes are burning and i cant figure out why its unhappy with the overloaded operator..

Answer 1

You are using ostream without qualifying it with namespace std::

The compiler errors/warnings are vaguely telling you that it has encountered a type that has not been declared yet.

friend std::ostream& operator << (std::ostream& out,const students& student);