Question

I have created a function template for loading my settings from a binary file.

template<class T> T LoadSettings(const std::string &fileName)
{
    // Load settings
    T settings;

    std::string filePath(LOCAL_FILE_DIR);
    filePath.append(fileName);

    std::ifstream file(filePath, std::ios::in | std::ios::binary);

    if (file.is_open())
    {
        if (!settings.ParseFromIstream(&file)) 
        {
            throw ExceptionMessage("Failed to parse TextureAtlasSettings");
        }
    }
    else
    {
        throw ExceptionMessage("Failed to open file");
    }

    return settings;
};

I would like to be able to invoke the function and return the appropriate settings class.

Coming from C# I would do the following.

MySettingsClass settings = LoadSettings<MySettingsClass>("FileName.bin");

How can I do the same thing in C++?

EDIT:

I should be more generic!

throw std::runtime_error("Failed to parse " + typeid(T).name());

Answer 1

Then use this syntax in C++

MySettingsClass settings = LoadSettings<MySettingsClass>(std::string("FileName.bin"));