Static Types

[djwilliams 0]

Hi

I am trying to implement a pattern known as the singleton which only allows 1 version of a class to be initailised here is the code (Note this is a Visual C++ implementation that I want to convert to BoostC++):

 

//Singelton .h

class device{

public:

device(void){deviceIndex=0; cout<< "creating Device "<<endl;};

~device(void){cout<<"device object is being destroyed: "<<endl;};

};

 

class Timer: public device

{

public:

Timer(void){cout<< "creating timer "<<endl;}

~Timer(void){cout<<"Timer object is being destroyed: "<<endl;}

};

 

class Timer3: public Timer

{

static Timer3 *pT3Instance; //SHOULD THIS BE static class Timer3* pT3Instance ?

Timer3(void){cout<< "creating timer3 "<<endl; }

public:

 

static Timer3* createTimer3(void);

 

~Timer3(void){}//{delete T3Overflow; cout<<"Timer3 object is being destroyed: "<<endl;}

 

};

 

 

//Singleton.cpp file

#include "singleton.h"

 

Timer3* Timer3::pT3Instance;

 

Timer3* Timer3::createTimer3(void)

{

if(pT3Instance==0)

{

pT3Instance= new Timer3();

cout<<"creating timer3 "<<pT3Instance<<endl;

}else{ cout<<"Timer3 already allocated exiting "<<pT3Instance<<endl;}

return pT3Instance;

}

 

//Test.cpp

#include "singleton.h"

 

Timer3* T3;

Timer3* T4;

int main(int argc, char* argv[])

{

T3=Timer3::createTimer3(); //THIS IS ONE AREA THAT I AM UNSURE HOW TO CODE WITH BoostC++

 

cout<< " Device Index= "<<T3->getDeviceIndex()<<endl;

T4=Timer3::createTimer3();

 

return 0;

}

 

Sorry about the cout statements this is a Visual C++ version that I am trying to convert to BoostC++ which has been unhappy with the C++ syntax shown here. Does anyone know how to convert this to BoostC++ so it compiles.

Many thanks

Dave

[Pavel 0]

This code won't work. BoostC++ does not support static members yet (It's on our work list).

 

Regards,

Pavel

[Pavel 0]

Both static variable members and static function members are now implemented in BoostC++. This feature will be available in the next release.

 

Regards,

Pavel