Question

Goal: To inherit from a class with 2 template parameters.

Error

Error error C2143: syntax error : missing ‘,’ before ‘<‘

The Code

template< typename Type >
class AssetManager : public IsDerivedFromBase< Type, Asset* >
{
    // Class specific code here
};

Things you need to know: Asset is a class that just wraps a char* with a getter/setter and IsDerivedFromBase will be used to basically test wether or not Type is a derivative of Asset. These sets of classes are isolated in there own small scale visual Studio 2012 project and will be integrated into the main project once all the functionality has been tested thoroughly.

Some Edits based on Comments

Thank you for the help so far, I really appreciate it. Here are some more specifics:

IsDerivedFromBase.h

#ifndef ISDERIVEDFROMBASE_H
#define ISDERIVEDFROMBASE_H

#include< iostream > // For access to NULL

namespace Fenrir
{
    template< typename Type, typename Base >
    class IsDerivedFromBase
    {
    private:
        static void Constraints( Type* _inheritedType )
        {
            Base* temp = NULL;

            // Should throw compiler error if
            // this assignment is not possible.
            temp = _inheritedType;
        }

    protected:
        IsDerivedFromBase( ) { void( *test )( Type* ) = Constraints; }
    };
}

#endif

Note: This class was based off of a class I read about in an article. I have since found a better way to achieve the desired result; however, I wish to understand where this error is stemming from.

AssetManager.h”

#ifndef ASSETMANAGER_H
#define ASSETMANAGER_H

#include "IsDerivedFromBase.h"

namespace Fenrir
{
    template< typename Type >
    class AssetManager : public IsDerivedFromBase< Type, Asset* >
    {
        // Class specific code
    };
}

#endif

Keeping class specific code to a minimum to keep this post as neat as possible, if more info is needed just let me know and I can add it in :).

Answer 1

Solved my issue which was interestingly silly. So due to a comment (from Jesse Good) I took a quick look at my includes. Since this was a small “whip it up quick” kind of project I didn’t really pay much attention to them. I don’t know exactly where the error was occuring, but I found out that AssetManager did not know about IsDerivedFromBase so I set up the following code block to just solve that issue without having to write a bunch of
#include statements everywhere!

// Contact point houses all of the include files
// for this project to keep everything in one place.

#ifndef CONTACTPOINT_H
#define CONTACTPOINT_H

#include "Asset.h"
#include "Sprite.h" 
#include "IsDerivedFromBase.h"
#include "GenericManager.h"
#include "AssetManager.h"   

#endif

Now I just include this in every header and all is well. I’ve been programming C++ for a little over a year now and never ran into this, a good lesson to learn for anyone new programming.

Thanks for your help everyone : )