Thread: 'cout' undeclared indentifier?

in one of my .cpp classes the prog doesn't realize that i have include iostream and VC++ gives me errors. Here is what I have:

Code:

//===================MAIN.CPP
#include <iostream>
#include <cstdlib>
#include "gridworld.h"
using namespace std;

int main()
{

	CGridworld test1(5, 5);
//...AND SO ON

//=====================gridworld.h
// File:  gridworld.h

#ifndef _GRIDWORLD_H
#define _GRIDWORLD_H

#include "DLList.h"
#include "personarray.h"

class CGridworld
{
  

  public:

    CGridworld(int nrows=5, int ncols=5);//constructor with gridsize
    //~CGridworld();

	void printMe(int r=5);

    void move(int pid, int new_row, int new_col); //move person pid to 
						  //  (new_row,new_col)
    void printMembers(int i, int j);	//print the people in district (i, j)

  private:

    int **Grid;	//two-dimentional array
    int nrows;			//number of rows in this grid world
    int ncols;			//number of columns in this grid world
    //CPersonArray P;		//stores person info
};


#endif

#include "gridworld.cpp"


//====================gridworld.cpp
CGridworld::CGridworld( int nrows, int ncols)
{
	Grid = new int*[nrows];

	for( int i = 0; i < nrows; i++)
	{
		Grid[i] = new int[ncols];
	}

}

void CGridworld::printMe(int r)
{
	for(int j=0; j<r; j++){
		cout << Grid[j] << endl;//the problem is here
	}
}

so the problem lies in either gridworld.h or .cpp. I'm not sure how to do it exactly. In GCC it seems to work fine?!

axon

try making it std::cout<<...

Originally posted by JaWiB
try making it std::cout<<...

I did try it and this is the error i am getting:

Code:

\CS201F03\prog1\gridworld.cpp(19) : error C2653: 'std' : is not a class or namespace name
\CS201F03\prog1\gridworld.cpp(19) : error C2065: 'cout' : undeclared identifier
CS201F03\prog1\gridworld.cpp(19) : error C2297: '<<' : illegal, right operand has type 'int *'
\CS201F03\prog1\gridworld.cpp(19) : error C2653: 'std' : is not a class or namespace name
\CS201F03\prog1\gridworld.cpp(19) : error C2065: 'endl' : undeclared identifier

axon

Perhaps VC wants every .h specified in the file that use it, I mean... try to put <iostream> in gridworld.h

I think you need to include your .h file in your .cpp file.

i've tried most everything i could think of, and nothing since to work.

>>Perhaps VC wants every .h specified in the file that use it, I mean... try to put <iostream> in gridworld.h

I know it could be done, but isn't this bad coding?

axon

everything works fine if I include iostream in gridworld.cpp as but why?!?

could this be a VC++ quirk?

axon

Originally posted by axon
everything works fine if I include iostream in gridworld.cpp as but why?!?

could this be a VC++ quirk?

axon

No, each .cpp file is compiled independantly of all others. Main.cpp is compiled without ever looking at girdworld.cpp. Gridworld.cpp is compiled without ever looking at main.cpp. Ever .cpp needs to #include anything it needs to use.

>>No, each .cpp file is compiled independantly of all others.
>>Main.cpp is compiled without ever looking at girdworld.cpp.

than why does the original code work on GCC?

axon

Exactly what lyx said; if you compile ONLY main.cpp, it would work.

BTW, a .cpp file should #include .h files, but a .h file should NEVER #include a .cpp, ever. That is terrible, terrible, terrible form. It IS good that you broke it up into pieces, but you are connecting the pieces wrong.

I think it's best to simply define the inline functions in the .h directly, and I think most people use this convention as well.

That makes sense with how it is compiled, too -- if you included a .cpp, that .cpp itself should not be compiled; this is counterintuitive.