Compiler cannot find member in an enum, the enum is declared in a separate header file, and defined in a source file

Question

I am very new to programming, and am using C++.

in my header file : Globals.h, I have declared both my enum, "Colour" and a function meant to test it.

In my source file, Globals.cpp, I have defined both the enum and the test function.

In main I call the function but am given this message:

Error C2027: Use of undefined type 'Colour'

and

Error C2065: 'COLOUR_BLACK': Undeclared identifier.

My code is below:

Globals.h

#ifndef GlOBALS_H
#define GLOBALS_H

enum class Colour;
void print_Colour(Colour whatColour);

#endif

and:

Globals.cpp

#include <iostream>
#include "Globals.h"


enum class Colour
{
    COLOUR_BLACK,
    COLOUR_BROWN,
    COLOUR_BLUE,
    COLOUR_GREEN,
    COLOUR_RED,
    COLOUR_YELLOW
};

void print_Colour(Colour whatColour)
{
    switch (whatColour)
    {
    case Colour::COLOUR_BLACK:
        std::cout << "Black" << "\n";
        break;
    case Colour::COLOUR_BROWN:
        std::cout << "Brown" << "\n";
        break;
    case Colour::COLOUR_BLUE:
        std::cout << "Blue" << "\n";
        break;
    case Colour::COLOUR_GREEN:
        std::cout << "Green" << "\n";
        break;
    case Colour::COLOUR_RED:
        std::cout << "Red" << "\n";
        break;
    case Colour::COLOUR_YELLOW:
        std::cout << "Yellow" << "\n";
        break;
    default:
        std::cout << "Who knows!" << "\n";
    }
}

and:

Source.cpp

#include <iostream>
#include "Globals.h"

using namespace std;

int main()
{
    Colour paint = Colour::COLOUR_BLACK; 
    print_Colour(paint);
    std::cin.get();
    std::cin.get();
    return 0;
};

Any help would be greatly appreciated!

score 4 · Answer 1 · answered Jul 01 '15 at 09:22

4

Source.cpp is only seeing the forward declaration. You should move the actual enum into the header file.

answered Jul 01 '15 at 09:22

Jonathan Potter

36,172
4
64
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score 1 · Accepted Answer · answered Jul 01 '15 at 09:21

1

enum class Colour must be defined in the header file Globals.h which you are including in Source.cpp. Otherwise, the definition of this enum is invisible within Source.cpp.

answered Jul 01 '15 at 09:21

m.s.

16,063
7
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Thanks! A question, you say it is invisible, but the function: print_Colour is not. Is this just how enums are? they cannot be defined in a source file unless they are being used in that same source file? – Peter Turner Jul 01 '15 at 09:41
Why is the function definition not invisible to source.cpp? – Peter Turner Jul 01 '15 at 09:41
@PeterTurner while you [can forward declare functions](http://stackoverflow.com/questions/4757565/c-forward-declaration), you [cannot forward declare enums](http://stackoverflow.com/questions/71416/forward-declaring-an-enum-in-c). – m.s. Jul 01 '15 at 10:41

Compiler cannot find member in an enum, the enum is declared in a separate header file, and defined in a source file

2 Answers2