question

i am getting one error when i try and compile this code, its in the last line when i try to output the date in the top node. anyone know why this is an error?

#include <iostream.h>
#include <fstream.h>
#include <string>

using namespace std;

struct StackFrame
{
string data;
StackFrame *link;

};

typedef StackFrame* StackFramePtr;



void main()
{
char array[1][5];
array[0][0] = 'h';
array[0][1] = 'e';
array[0][2] = 'l';
array[0][3] = 'l';
array[0][4] = 'o';
StackFramePtr top;
top = new StackFrame;
top->data = array[0];
top->link = NULL;
cout << top->data;
}

What's the error?

Kuphryn

something about the cout << top->data
here it is......

--------------------Configuration: cpp2d - Win32 Debug--------------------
Compiling...
cpp2d.cpp
C:\Documents and Settings\owner\cpp2d.cpp(30) : error C2679: binary '<<' : no operator defined which takes a right-hand operand of type 'class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >' (or there is no accepta
ble conversion)
Error executing cl.exe.

cpp2d.obj - 1 error(s), 0 warning(s)

Weird. Consider c_str().

data.c_str()

Kuphryn

Dont know, but ditch the .h's on those header files, u used namespace.

ok getting rid of the .h worked. it outputs hello like it should but theres also some junk being output after it. any sugestions on how to get rid of this junk?

never mind......i figured it out. i was just wondering, how come you cant use that using namespace with .h on the header files. what if i wanted to use both. i dont really understand what using namespace does

To my understanding it pulls everything into the standard namespace. Using .h is the old way of declaring, no reason to do it.

>how come you cant use that using namespace with .h on the header files.
The old headers are typically defined like this:

Code:

// iostream.h
#ifndef __IOSTREAM_H
#define __IOSTREAM_H

#include <istream.h>
#include <ostream.h>

// ...

#endif

The new ones are slightly different:

Code:

// iostream
#ifndef __IOSTREAM
#define __IOSTREAM

#include <istream>
#include <ostream>

namespace std {
  // ...
}

#endif

With the old headers you don't have to tell the compiler to look anywhere except the header itself. The new headers require you to look in the header and then in the std namespace to find what you want. The directive:

Code:

using namespace std;

tells the compiler that if the name is in the std namespace, it should be accessable without resolving the namespace manually. In other words, you can say this:

Code:

cout<<"cout from namespace std"<<endl;

instead of the manual namespace resolution:

Code:

std::cout<<"cout from namespace std"<<std::endl;

-Prelude