Two classes problem

[venomxxl]

I'm writing a small game engine and I have a little problem. The code below shows the exact situation:

Header1.h

#ifndef _HEADER1
#define _HEADER1

#include "Header2.h"

namespace HNamespace
{
	class HClass1
	{
		public:
			HClass1()
			{
				
			}
			
			~HClass1()
			{
				
			}
			
		HClass2 * A;
		
	};
}

#endif

Header2.h

#ifndef _HEADER2
#define _HEADER2

#include "Header1.h"

namespace HNamespace
{
	class HClass2
	{
		public:
			HClass2()
			{
				
			}
			
			~HClass2()
			{
				
			}
			
		HClass1 * A;
		
	};
}

#endif

Main.cpp

#include "Header1.h"
#include "Header2.h"

int main(int argc, char ** argv){
	
	return 0;
}

Output:
header2.h(21) : error C2143: syntax error : missing ';' before '*'
header2.h(21) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
header2.h(21) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

First error obviously says that HClass1 is not recognised in HClass2. Others are not that important, because they are caused by the first error.

I get that when I use HNamespace::HClass1 instead of just HClass1:
header2.h(21) : error C2039: 'HClass1' : is not a member of 'HNamespace'
(... and the first ones)

Interestingly I don't get any errors on the line where I declare

friend class HClass1;

in HClass2.

I know I can just use "void *" instead of "HClass1 *" and the errors will disappear, but I'd like to see the class names instead of "void".

My questions are: What is happening? What is the solution to that problem?

(I have a feeling the solution is obvious...)

Thanks
Marek

[Ketsuekiame]

Ok what you need to do is at the beginning of the header file for one of the classes. You need to declare that there "will be a class of this type". You then drop the include for that class from the file.

So take HClass1:

#ifndef _HEADER1
#define _HEADER1


namespace HNamespace
{
        class HClass2;

	class HClass1
	{
		public:
			HClass1()
			{
				
			}
			
			~HClass1()
			{
				
			}
			
		HClass2 * A;
		
	};
}

#endif

You can then leave your HClass2 file as it is.

Edit: You need to make sure your HClass2 file is included somewhere else in the program

[venomxxl]

Wow, it worked! Thank you :).

Well I didn't think of that way to do it. I will try it with my game engine after I finish my dinner.

This problem is solved.

Thank you again
Marek