Sharing Header files (Visual Studio 2017)

[hassanAman]

Hello, the problem is, I'm not able to share the files I need, the compiler gives a disgusting and very annoying errors.

My first header file "Game.h" : (i'm only going to show you what it includes)

#include "SDL.h"
#include "Handler.h"
#include "Player.h"

My second header file "GameObject.h" :

#include "SDL.h"
#include "SDL_image.h"
#include <vector>

My third header file "Handler.h"

#include <vector>
#include "GameObject.h"
#include "Block.h"
#include <algorithm>
#include "GearDoor.h"

My fourth header file "Player.h"

#include "GameObject.h"
#include "Handler.h"

My fifth header file "Block.h"

#include "GameObject.h"
#include "Handler.h"

My sixth header file "GearDoor.h"

#include "GameObject.h"
//right here I want to include the file called "Handler.h"
//It does not give me an error, but as soon as I make a pointer to
//Handler, it starts giving me some huge errors.
//please someone help me, so I can finish making my game.

[Ganado]

Circular dependency.
You want GearDoor.h to depend on Handler.h, but Handler.h depends on GearDoor.h

There's some messy logic happening. You should probably think about on paper to figure what actually needs to include what.

Note that pointers can be declared after the class is declared, but before the implementation is. This is because the size of the pointer does not depend on the size of the class.

class A;

class B { A* a; };

class A {
    void foo() {}
};

If you're still having troubles, post the actual error messages (at least the first few), and relevant code lines.

[hassanAman]

Sir, the errors are always the same, here :
Some lines Keep repeating

1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2143: syntax error: missing ';' before '*'
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2238: unexpected token(s) preceding ';'
1>Generating Code...
1>Compiling...
1>Game.cpp
1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2143: syntax error: missing ';' before '*'
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2238: unexpected token(s) preceding ';'
1>Generating Code...
1>Compiling...
1>GearDoor.cpp
1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>Generating Code...
1>Compiling...
1>main.cpp
1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2143: syntax error: missing ';' before '*'
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2238: unexpected token(s) preceding ';'
1>Player.cpp
1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2143: syntax error: missing ';' before '*'
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2238: unexpected token(s) preceding ';'
1>Handler.cpp
1>c:\users\hassa\source\repos\game\game\geardoor.h(3): warning C4067: unexpected tokens following preprocessor directive - expected a newline
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2143: syntax error: missing ';' before '*'
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\hassa\source\repos\game\game\geardoor.h(22): error C2238: unexpected token(s) preceding ';'
1>Generating Code...
1>Skipping... (no relevant changes detected)
1>GameObject.cpp
1>Done building project "Game.vcxproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

[coder777]

The reason is that "Handler.h" includes already "GearDoor.h". So you have a circular include which causes the error. This hints at some design problems.

I suggest that you do not include "GameObject.h" and "GearDoor.h" in the central header "Handler.h". Instead use Forward declaration. like so:

https://en.wikipedia.org/wiki/Forward_declaration

class GameObject; // forward declaration

instead of

#include "GameObject.h"

Note that in your implementation file (*.cpp) you can actually include everything. Only in the header itself it is problematic.

[hassanAman]

So you are saying that, instead of having all the include files in the .h, i have it in the .cpp?

[Repeater]

Any file, header or source, should ONLY include a header if it's needed in that file. Needed.

[hassanAman]

kk