Namespace declared in Header file is not being recognized in Source File

Question

What am i doing wrong here?

APP.h

#pragma once

namespace App{

    enum class AppStatus{
    Exit,
    Menu,
    Run
    };

    void frameLoop();

    AppStatus state;

}

App.cpp

#include "App.h"
#include "stdafx.h"
#include <Graphic\Graphic.h>


void App::frameLoop()
{
    while (state != AppStatus::Exit) {

        Graphic::renderingSequence();
    }
}

Errors

Error   C2653   'App': is not a class or namespace name App 
Error   C2065   'state': undeclared identifier  App 
Error   C2653   'AppStatus': is not a class or namespace name   App 
Error   C2065   'Exit': undeclared identifier   App

Note that my namespace Graphic (declared in \Graphic\Graphic.h) is being recognized by the compiler, even though i declared it just the same way.

`#include "stdafx.h"` Must always be the first non comment line. All lines above that are ignored by the compiler. — drescherjm, Dec 16 '16 at 21:06
Thanks! will have to learn more about what exactly is special about `#include ` — stimulate, Dec 16 '16 at 21:08
@drescherjm I did not find anything that helped me, because i did not expect that #include can have variable functionality — stimulate, Dec 16 '16 at 21:11
http://stackoverflow.com/questions/16040689/why-stdfax-h-should-be-the-first-include-on-mfc-applications — drescherjm, Dec 16 '16 at 21:15
@stimulate If you are clear now, please click on the big green check mark below. — Jive Dadson, Dec 16 '16 at 23:14

score 2 · Accepted Answer · edited May 23 '17 at 12:08

2

stdafx.h (Microsoft precompiled header) must be at the top. This applies to any Visual C++ project with the precompiled headers option turned on, and stdafx.h the standard pch. Those are the default settings for a new project.

Purpose of stdafx.h

The simplest and least error-prone way to define the function within the namespace App is just to put it there.

APP.CPP

#include "stdafx.h" // Nothing goes above this
#include "App.h"
#include <Graphic\Graphic.h>

namespace App {
    void frameLoop()
    {
        while (state != AppStatus::Exit) {
            Graphic::renderingSequence();
        }
    }
}

edited May 23 '17 at 12:08

Community

1
1

answered Dec 16 '16 at 22:36

Jive Dadson

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I agree with Jive you should put the function in the namespace rather than saying App::frameLoop(). It might be confusing for people and they might think App is a class. – Lasse Jacobs Dec 16 '16 at 22:55
More importantly, the code in the cpp file will automatically resolve names the same as the .h file does. E.g. AppStatus::Exit. – Jive Dadson Dec 16 '16 at 22:58

Namespace declared in Header file is not being recognized in Source File

1 Answers1