Hi, to achieve what is hinted in the title would save me a lot of code duplication. So here's the problem:

All of my externals contain at least these ingredients

In my case there's one class/file containing the functions (which need the key to work)

and there are "sub"files which import the header of that topfile.

Now I would like to use the same methods of that topfile for different max_structs

which depend on that key, knowing that all structs will have that key.

in the topfile because I thought it might work having the same structure but didn't.

Hi, to achieve what is hinted in the title would save me a lot of code duplication. So here's the problem: 

typedef struct
{
    t_object standart_header;
    int key;
}t_specific_struct;

In my case there's one class/file containing the functions (which need the key to work)
and there are  "sub"files which import the header of that topfile.

Now I would like to use the same methods of that topfile for different max_structs
which depend on that key, knowing that all structs will have that key. 

typedef struct
{
    t_object standart_header;
    int key;
}t_generic_struct;

in the topfile because I thought it might work having the same structure but didn't.


different-max_structs-using-the-same-method-polymorphism

-----------pseudo-code--------------------

class_addmethod(c, (method)test_method, "test", 0);

// I'd like to avoid this and use "test_method_super" directly

---------------------------------------------------

//generic part - the test_super.c file - how I want it to work

void test_method_super(t_generic_struct * x)

do s.th with the key of x; //not possible at the moment

--------------------------------------------------

If a method interface allows different types as parameters, isn't that (parametric )polym.?

-----------pseudo-code--------------------
//specific part

#import "test_super.h"
int main (int argc, const char * argv[])
{
...
           class_addmethod(c, (method)test_method, "test", 0);
}

// I'd like to avoid this and use "test_method_super" directly
void test_method(t_specific_struct *x)
{
          test_method_super(x->key);
}

---------------------------------------------------
//generic part - the test_super.c file - how I want it to work 

void  test_method_super(t_generic_struct * x)
{
        do s.th with the key of x; //not possible at the moment
}
--------------------------------------------------
If a method interface allows different types as parameters, isn't that (parametric )polym.?


this is one of the reasons why I develop my externals in C++ instead of C. Just search the net for 'object oriented programming'. If in C++, you should check the part where they talk about 'virtual functions'.

I got it working with something like Nicolas proposed. Thanks a lot!

I made a struct that contains t_object and the key

Using t_ob as the generic type directly didn't work. All values received were 0.

and then using this type in the super method works!

Every object that contains the t_things_in_common struct in first place can use functions

which have t_generic as a parameter type.

Again thanks for helping out, also for the advice having a look at c++.

Hi,
I got it working with something like Nicolas proposed. Thanks a lot!

typedef struct _ob {
    t_object o;
    int key;
} t_things_in_common;

typedef struct
{
	t_things_in_common ob;
}t_generic;

void test_method_super(t_generic * x)
{
do s.th with the key of x; //works now
}

Every object that contains the t_things_in_common struct in first place can use functions
which have t_generic as a parameter type.

typedef struct
{
    t_things_in_common
    ...more ingredients;
}t_specific;

Again thanks for helping out, also for the advice having a look at c++.
Greetings, Alex


different max_structs - using the same method - polymorphism