File Causing Thousands of Errors (C++) [closed] - c++

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This class below is causing a horrendous amount of errors. It appears to be fine though. Any C++ Gurus around who know why VC++ hates me?
Entity.h
#pragma once
#include "World.h"
#include "Renderer.h"
class Entity {
public:
Entity(World* world, Coordinate coord);
~Entity();
void render(Renderer renderer) const;
World* world;
Coordinate coord;
};
Entity.cpp
#include "Entity.h"
Entity::Entity(World* world, Coordinate coord) : world(world), coord(coord) {
world->entities.insert(this);
}
Entity::~Entity() {
world->entities.erase(this);
}
The errors themselves don't make a whole lot of sense as they aren't even related to this file. Some of the common errors are unexpected end of file, missing ';' before '{' and "Entity is not a class or namespace name". Those errors do not occur when I do not include Entity in my project. The last of those errors appear in the declaration code of Entity.
The errors (With all duplicates removed): http://pastebin.com/TEMEhVZV
World.h
#pragma once
#include <map>
#include <vector>
#include <unordered_set>
#include "Chunk.h"
#include "Coordinate.h"
#include "Renderer.h"
class World {
public:
~World();
void generateChunk(Coordinate coord);
void loadChunk(Coordinate coord);
void renderWorld(Renderer* renderer);
std::unordered_set<Entity*> entities;
inline Chunk* getChunk(Coordinate coord) const {
return loadedChunks.at(coord);
}
private:
std::map<Coordinate, Chunk*> loadedChunks;
};
Renderer.h
#pragma once
#include <SFML/Window.hpp>
#include <SFML/OpenGL.hpp>
#include "World.h"
class Renderer {
public:
sf::Window *window;
void bind(sf::Window* newWindow);
void initializeOpenGL();
void renderChunk(Chunk* chunk);
inline void drawPoint(Coordinate coord) {
glBegin(GL_POINTS);
glVertex3d(coord.x, coord.y, coord.z);
glEnd();
}
private:
template <class T>
inline static void pushVector3(std::vector<T>* vertices, T x, T y, T z);
};

Answer 1

To me, it looks like a circular header dependency, meaning something can't be defined.
If your Renderer.h file has a method acting upon an Entity object, and contains this header file as a dependency, Entity will have to be declared before Renderer can be compiled. (The compiler needs to know how big an Entity object will be so it can hard-code the stack offset.)
But similarly, Renderer needs Entity. So it can't be compiled, either!
This may not have shown up in your project before, because the header files are loaded in a different order than now, when the 'Entity' header triggers them.
So, what you should do is modify the headers so there are no circular dependencies, and then reference only pointers in the header, since they have fixed, known sizes. Here are some tricks:
Include low-level classes instead of higher ones.
#include "World.h"
-->
#include "Coordinate.h"
class World;
Use pointers.
#include "Renderer.h"
void render(Renderer renderer) const;
-->
class Renderer;
void render(Renderer* renderer) const;
Doing these, the header files can be moved to your .cpp file:
#include "Entity.h"
#include "World.h"
#include "Renderer.h"

Answer 2

Try going to the very first error its spits out, and fixing that one. In VC++ double-clicking there should take you to the line in question. Often times after the first error or two the compiler is so hopelessly confused that nothing else in its output is worth looking at.
My suspicion would be that it will take you to a line in one of those header files you are not displaying.

Answer 3

It's hard to give too much help without more context. In my experience, errors like this almost always relate to a missing semicolon. Are you given a file and line number with those errors? I would check in Renderer.h, and make sure it is not missing a semicolon.
The reason I suggest this is because, when you #include a file, the compiler actually copies it in to this file. That means that typos in previous files can manifest themselves in these files. If you can post more information, or even copy and paste the errors themselves, I'll try to be more helpful.
EDIT:
Since you've posted your errors, this makes much more sense. If you look, the first error in the list is actually number 148. You have to scroll down for error number 1:
"Error 1 error C2065: 'Entity' : undeclared identifier world.h"
To me, this looks like you're trying to use the class Entity in the file world.h, and it doesn't exist yet. So this looks like a circular include problem.