flipcode - Simple RTTI For C++

Simple RTTI For C++
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This is some very simple RTTI (run time type information) code that you can use for C++. Similar to Java's instanceof operator, it allows you to take a base pointer from some object and see if it is an instance of a derived class.

It consists of some simple defines:

#define setClassname0(name) \
 virtual char *getClassname(){return name;} \
 virtual bool isInstanceOf(const char *classname)
 {return (strcmp(classname,name)==0 ? true : false);}

#define setClassname1(name,parent) \
 virtual char *getClassname(){return name;} \
 virtual bool isInstanceOf(const char *classname)
 {return (strcmp(classname,name)==0 ? true : parent::isInstanceOf(classname));}

#define setClassname2(name,parent1,parent2) \
 virtual char *getClassname(){return name;} \
 virtual bool isInstanceOf(const char *classname)
 {return (strcmp(classname,name)==0 ? true : (parent1::isInstanceOf(classname) || parent2::isInstanceOf(classname)));}

And say you have the following code:

class Furniture{
public:
    setClassname0("Furniture");
    ...
};

class Chair:public Furniture{
public:
    setClassname1("Chair",Furniture);
    ...
};

class Table:public Furniture{
public:
    setClassname1("Table",Furniture);
    void doTableStuff();
    ...
};

And if you have a pointer to a Furniture, you could check to see if it is really an instance of a Table or not, before you actually make the cast:

Furniture *pFurniture=getSomeFurniture();

if(pFurniture-isInstanceOf("Table"){
    ((Table*)pFurniture)-doTableStuff();
}

So in this case, pFurniture->isInstanceOf("Table") would return true, pFurniture->isInstanceOf("Furniture") would also return true, but pFurniture->isInstanceOf("Chair") would return false.

The setClassname2 could be used if you wanted to do multiple inheritance.

Hope this might be useful to someone. And anyone can use this code for whatever.