Thread: Headache error message

okay, I keep getting this compiler error message:

Undefined. . . . . . . . . . . . . . . . . first referenced
symbol. . . .. . . . . . . . . . . . . . . . . . . in file
rob::Book::~Book() . . . . . . . . . . . /var/tmp//ccZWEnnc.o
rob::Book::Book() . . . . . . . . . . . . /var/tmp//ccZWEnnc.o
ld: fatal: Symbol referencing errors. No output written to a.out
collect 2: ld returned 1 exit status

rob::Book::~Book() <===this is the destructor for class Book in namespace rob that I created, the other one is the default constructor. I've tried everything I can think of and more. I need some serious help, I still have a lot left to work on for this project lol

Code:

//class header file
#include <string>
#include <cstdlib>

using namespace std;

namespace rob
{
  class Book
  {
    public:
      ~Book();
      Book (const Book& b1);
      void operator =(const Book& b1);
      Book();
      void print (ostream& outs);
      void fill (istream& ins);
    private:
      string* title;
      string* author;
      int copies, dollars, cents;
  };
}

//implementation file. I'll only put the destructor and default
//constructor because those are the problem ones

#include <iostream>
#include <cstdlib>
#include <string>
#include <fstream>
#include <cctype>
#include "book.h" //header file

using namespace std;
using namespace rob;

namespace rob
{
  Book::~Book()
  {
    delete title;
    delete author;
   }
   Book::Book()
   {
     title = new string;
     author = new string;
     copies = 0;
     dollars = 0;
     cents = 0;
    }
    //etc etc etc, the rest works fine
}

//main program, just testing to see if it compiles (which it doesn't)

#include "book.h"

using namespace std;
using namespace rob;

int main()
{
  Book b1;
  return 0;
}

if you see anything that could be wrong please help. I had it working fine as one file, but when I split it up it stopped working

I believe your problem is that you declared you were using a namespace before you defined it.

I don't think the problem is with the namespace. I defined namespace rob in the header file. I'm just adding the implementation to it in the other one. I don't get an error message with the other functions in my class, just with the default constructor and the destructor

Originally Posted by Strait

okay, I keep getting this compiler error message:

Undefined. . . . . . . . . . . . . . . . . first referenced
symbol. . . .. . . . . . . . . . . . . . . . . . . in file
rob::Book::~Book() . . . . . . . . . . . /var/tmp//ccZWEnnc.o
rob::Book::Book() . . . . . . . . . . . . /var/tmp//ccZWEnnc.o
ld: fatal: Symbol referencing errors. No output written to a.out
collect 2: ld returned 1 exit status

rob::Book::~Book() <===this is the destructor for class Book in namespace rob that I created, the other one is the default constructor. I've tried everything I can think of and more. I need some serious help, I still have a lot left to work on for this project lol


if you see anything that could be wrong please help. I had it working fine as one file, but when I split it up it stopped working

How did you comple the program?

I put your header stuff in "book.h", the implementation stuff in "rob.cpp" and the main stuff in "main.cpp".

Then:

g++ rob.cpp main.cpp -Wall -pedantic

No compiler messages.

g++ main.cpp
...Temp/ccMICfav.o(.text+0x25):main.cpp: undefined reference to `rob::Book::Book[in-charge]()'
...Temp/ccMICfav.o(.text+0x30):main.cpp: undefined reference to `rob::Book::~Book [in-charge]()'
collect2: ld returned 1 exit status

Regards,

Dave

HA! success. I just got rid of the pointers and the big 3. I misread the directions my professor gave me. I'm not supposed to use dynamic memory until the second part of this program lol.