dynamic create

#include 

#include 

#include 

#include 

#define DECL_CLS(name)  static CRuntimeClass gCClass ## name; CRuntimeClass* type(){return &gCClass ## name;}

#define IMPL_CLS(name, base) CRuntimeClass name::gCClass##name(#name, &gCClass##base);

#define IMPL_CLS0(name) CRuntimeClass name::gCClass##name(#name, 0);

class CObjectBase;

class CRuntimeClass

{

    const char *clsname;

    CRuntimeClass *baseclass;

    static std::map<std::string, CRuntimeClass*> classmap;

 public:

    CRuntimeClass(const char *name, CRuntimeClass *base) :clsname(name), baseclass(base){

        classmap[name] = this;

    }

    static CRuntimeClass* get_by_name(const char *n){

        auto it = classmap.find(n);

        return it==classmap.end()?0:it->second;

    }

    bool is_base_of(CRuntimeClass *p)

    {

        for(;p;p=p->baseclass)

        {

            if(p==this)

            return true;

        }

        return false;

    }

    //static CObjectBase* create();

};

std::map<std::string, CRuntimeClass*> CRuntimeClass::classmap;

class CObjectBase{

public:

    virtual ~CObjectBase(){}

    DECL_CLS(CObjectBase)

};

IMPL_CLS0(CObjectBase)

//CObjectBase* CRuntimeClass::create(){return new ;}

class classA:public CObjectBase

{

public:

    DECL_CLS(classA)

};

IMPL_CLS(classA, CObjectBase)

using namespace std;

int main()

{

    classA a;

    CObjectBase o;

    assert(o.type()->is_base_of(a.type()));

    //CObjectBase *pa=CRuntimeClass::get_by_name("classA")->

    cout << "Hello World!" << endl;

    return 0;

}