Singleton pattern

Singleton pattern... People love it or hate it. There are also group of people who don't mind them.

I'm still try figure out which I'm :] I'm for sure not the one who love them. I'm also cannot say that I rally hate them because I still use them in code (It is like with my Facebook account. After I created one I try not complain about fb. ). So probably I'm best fit to don't mind group.

But my past experience showing me that I have bigger tendency to removing them from code than adding new one. And probably some colleagues from work will be happy about this because we spend a lot of time discussing about problem.

I remove them because I put even more effort in good design of systems. In a lot of cases thanks to changes I just don't need global objects. Which is good. It allow me to better utilize multithreading thanks to encapsulation.

Today sadly I had problem where I still don't know cleaner solution than global state:

//////////////////////////////////////////////////////////////////////////
template<> bool write<CResHandle>( ISerializerWriter& a_writer, const CResHandle& a_value )
{
    return a_writer.serialize(a_value.isValid() ? a_value->getId() : wrResourceID());
}

//////////////////////////////////////////////////////////////////////////
template<> bool read<CResHandle>( ISerializerReader& a_reader, CResHandle& a_value )
{
    wrResourceID id;

    if (!a_reader.deserialize(id)) return false;

    if (CResource::isValid(id))
    {
        a_value = getResMgr()->createResource(id);
    }
    else
    {
        a_value = nullptr;
    }

    return true;
}

Function getResMgr() return global resource manager. I don't want to pass it around inside arguments because this is ugly and I would need to do the same with each manager I want to use. This would increase my arguments list and each new manager would recommend changes in all write/read functions.

I thought maybe about storing inside ISerializerReader/ISerializerWriter function like setData()/data() in some Qt classes. This way it will be really easily to extend list of available data even by game (which may add some new write/read functions). 

I'm still not sure about this solution and how nice it is. I will spend some time thinking about it but for now I will leave getResMgr() use with nice macro call right before it : 

WR_TODO("gwojciechowski", "Think about way to not use global getResMgr().");

If you have any idea, thoughts or you just want to comment this. I'm open on opinion how to make this nice and clean :]

Greg