interesting but not useful

the following came from http://home.earthlink.net/~huston2/dp/AdapterDemosCpp
but its limited can only work on a void function.

// Purpose. Adapter design pattern (External Polymorphism demo)

// 1. Specify the new desired interface
// 2. Design a "wrapper" class that can "impedance match" the old to the new
// 3. The client uses (is coupled to) the new interface
// 4. The adapter/wrapper "maps" to the legacy implementation

#include

class ExecuteInterface { public: // 1. Specify the new i/f
virtual ~ExecuteInterface() { }
virtual void execute() = 0;
};

template // 2. Design a "wrapper" or
class ExecuteAdapter : public ExecuteInterface { // "adapter" class
public:
ExecuteAdapter( TYPE* o, void (TYPE::*m)() ) { object = o; method =m; }
~ExecuteAdapter() { delete object; }
// 4. The adapter/wrapper "maps" the new to the legacy implementation
void execute() /* the new */ { (object->*method)(); }
private:
TYPE* object; // ptr-to-object attribute
void (TYPE::*method)(); /* the old */ // ptr-to-member-function
}; // attribute

// The old: three totally incompatible classes // no common base class,
class Fea { public: // no hope of polymorphism
~Fea() { cout << "Fea::dtor" << endl; }
void doThis() { cout << "Fea::doThis()" << endl; }
};

class Feye { public:
~Feye() { cout << "Feye::dtor" << endl; }
void doThat() { cout << "Feye::doThat()" << endl; }
};

class Pheau { public:
~Pheau() { cout << "Pheau::dtor" << endl; }
void doTheOther() { cout << "Pheau::doTheOther()" << endl; }
};

/* the new is returned */ ExecuteInterface** initialize() {
ExecuteInterface** array = new ExecuteInterface*[3]; /* the old is below */
array[0] = new ExecuteAdapter( new Fea(), &Fea::doThis );
array[1] = new ExecuteAdapter( new Feye(), &Feye::doThat );
array[2] = new ExecuteAdapter( new Pheau(), &Pheau::doTheOther );
return array;
}

void main( void ) {
ExecuteInterface** objects = initialize();

for (int i=0; i < 3; i++) objects[i]->execute(); // 3. Client uses the new
// (polymporphism)
for (i=0; i < 3; i++) delete objects[i];
delete objects;
}

// Fea::doThis()
// Feye::doThat()
// Pheau::doTheOther()
// Fea::dtor
// Feye::dtor
// Pheau::dtor