• "dt" <tinkham ucalgary.ca> May 09 2005
• "dt" <tinkham ucalgary.ca> May 27 2005

DMC Compiler version 8.42n
Win2K
IDDE
-WD

I have a class that I am exporting during compilation for building a dll.

I am getting the "cannot find constructor" error during compilation, in
AbstractContainer::init(). Here is the error exracted from source listing
file:

void AbstractContainer::init()
{

 controlHandler_ = new ControlEvHandler<AbstractContainer>( this,
                                  &AbstractContainer::containerResized);
                                                                       ^
AbstractContainer.cpp(26) : Error: cannot find constructor for class
matching ControlEvHandler<AbstractContainer
::ControlEvHandler<AbstractContainer >(AbstractContainer*,void (



                                  &AbstractContainer::containerResized);

}



I believe the problem is with "AbstractContainer::*__export member func" in
output error above, which is expecting a pointer to an exported member
function.  If I do not export the member function, the error disappears.

Here is some of the code that hopefully can illustrate the problem.




//================ from EventHandler.h ============================

class __declspec(dllimport) EventHandler {  //yes, importing this one
public:

 EventHandler(){}

 ~EventHandler(){}

      // code removed

};


//  Note the fct. pointer typedef below. This will be the fct. pointer to
AbstractContainer::containerResized

template <class SOURCE, class EVENT>
class EvHandInst : public EventHandler {
public:
 typedef void(SOURCE::*OnEvHandMethod)( EVENT* e );


 EvHandInst( SOURCE* source, OnEvHandMethod handlerMethod) {
  source_ = source;
  handlerMethod_ = handlerMethod;
 }

 virtual ~EvHandInst(){
 }

protected:
 SOURCE* source_;
 OnEvHandMethod handlerMethod_;

};





//=============  from AbstractContainer.h ===================


class __declspec(dllexport) ControlEvent {
public:
    ControlEvent( );

    ~ControlEvent();
    //code removed

};



template <class SOURCE_TYPE>
class ControlEvHandler : public EvHandInst<SOURCE_TYPE,

ControlEvent> {
public:

    ControlEvHandler( SOURCE_TYPE* source,
       EvHandInst<SOURCE_TYPE, ControlEvent>::OnEvHandMethod handlerMethod)
:
       EvHandInst<SOURCE_TYPE, ControlEvent>( source, handlerMethod)
    {
    }

};


class __declspec(dllexport)  AbstractContainer  : public Container  {
public:

 AbstractContainer();

 virtual ~AbstractContainer();

 void init();

protected:

 EventHandler* controlHandler_;

 void containerResized( ControlEvent* event );

private:
    int dumb_;

};


member init() creates an ControlEvHandler (has base class EventHandler), and
note I am passing the address of (exported) member
AbstractContainer::containerResized. The error occurs in this fct., because
it can't find a constructor taking an exported member fct. address?


void AbstractContainer::init()
{

    controlHandler_ = new ControlEvHandler<AbstractContainer>( this,
                               &AbstractContainer::containerResized);

}


I am thinking the problem is the syntax of the typedef of fct. pointer in
class EvHandInst:

typedef void(SOURCE::*OnEvHandMethod)( EVENT* e );


but I am not sure of this.

Is there a special way to note a fct. pointer is to an exported member fct?
Or, am I doing something else wrong here?  I ask here, because I don't get
this error with some other compilers, and am thinking I just need slightly
different (correct) syntax for DMC compiler.

Thanks for any help.

"dt" <tinkham ucalgary.ca> wrote in message
news:d5pfrr$dov$1 digitaldaemon.com...
 I am thinking the problem is the syntax of the typedef of fct. pointer in
 class EvHandInst:

 typedef void(SOURCE::*OnEvHandMethod)( EVENT* e );


 but I am not sure of this.

 Is there a special way to note a fct. pointer is to an exported member fct?
 Or, am I doing something else wrong here?  I ask here, because I don't get
 this error with some other compilers, and am thinking I just need slightly
 different (correct) syntax for DMC compiler.

 Thanks for any help.


Well, I guess DMC wants exactly what it is asking for. If I change

  typedef void(SOURCE::*OnEvHandMethod)( EVENT* e );

to

  typedef void(SOURCE::*__export OnEvHandMethod)( EVENT* e );

Then this particular error message is removed. However, we have classes (with
member funcs) that are not exported, and when they use the above code with
__export added, we get the corresponding error message for the case where the
'constructor' without __export cannot be found.

It seems odd that all the VC, borland, CW, and MinGW gcc3.3.1 can handle all
this transparently. Is this a compiler bug, or no?

Doug