class inheritance and compilation problem. Linux RH6.2. g++

[Maciej Kwapulinski]

Halo
I have a problem with the following program:

#include <stdlib.h>

struct Base {
int a;
Base() {
a=0;
}
Base(int a): a(a) {};
};

class InherInher;

struct Inher: public Base {
Inher(int a): Base(a) {};


// this is the problem
struct Base* getObj() {
Base *ptr = new InherInher( a );
return ptr;
}
};

struct InherInher: public Inher {
InherInher(int a): Inher( a ) {};
};

main() {
}

Have You got any ideas how to make it work

Greetings
Maciej

 

[Victor Bazarov]

I have a problem with the following program:

#include <stdlib.h>

I don't think you use anything from this header here.

struct Base {
int a;
Base() {
a=0;
}
Base(int a): a(a) {};

Lose the trailing semicolon.

};

class InherInher;

struct Inher: public Base {
Inher(int a): Base(a) {};

Lose the trailing semicolon.

// this is the problem
struct Base* getObj() {
Base *ptr = new InherInher( a );
return ptr;
}

Move it down after the 'InherInher' definition and declare it
inline. Leave only a declaration here:

Base* getObj();

};

struct InherInher: public Inher {
InherInher(int a): Inher( a ) {};

Lose the trailing semicolon.

};

Here is where you move the member definition:

inline Base* Inher::getObj() {
Base *ptr = new InherInher( a );
return ptr;
}

main() {

int main() {

}

Have You got any ideas how to make it work

See above

Victor

 

[Karl Heinz Buchegger]

[snip]

Have You got any ideas how to make it work

There is no other way then to move the definition
of function Inher::getObj() past the declaration
of InherInher

....

struct Inher: public Base {
Inher(int a): Base(a) {};
struct Base* getObj();
};

struct InherInher: public Inher {
InherInher(int a): Inher( a ) {};
};

struct Base* Inher::getObj()
{
Base *ptr = new InherInher( a );
return ptr;
}

int main()
{
}

 

[Maciej Kwapulinski]

That's it !!
Great thanks

I don't think you use anything from this header here.



Lose the trailing semicolon.



Lose the trailing semicolon.


Move it down after the 'InherInher' definition and declare it
inline. Leave only a declaration here:

Base* getObj();


Lose the trailing semicolon.


Here is where you move the member definition:

inline Base* Inher::getObj() {
Base *ptr = new InherInher( a );
return ptr;
}


int main() {


See above

Victor