This code works:

alias void delegate(int) t_func;

class Foo
{
  t_func func1;

  void dothis()
  {
    if (func1) func1(4); else
      printf("func1 not assigned\n");
  }

  void func(int num) { printf("num = %d\n", num); }
}

int main(char[][] args)
{
  Foo a = new Foo;
  a.dothis();
  a.func1 = &a.func;
  a.dothis();
  return 0;
}

Result:  func1 not assigned
         num = 4

However, if I move the func declaration to outside of the class, the line "a.func1 = &func" produces the error message:  toelem: cannot cast from void(*)(int num) to void delegate(int).
If I then change the t_func declaration from alias to typedef then I get:  cannot implicitly convert void(*)(int num) to t_func.
If I go back to the original working code and change alias to typedef then I get:  Internal error: e21r.c 78

What are the reasons for these error messages?  It seems to me that all of these senarios should work.

Thanks,

Paul

Delegates are a combination of function pointer with a 'this' pointer. Hence, a function outside of a class can't be a delegate. I'll check into the internal error. Thanks, -Walter

"Paul Runde" <prunde@mcleodusa.net> wrote in message news:3DB37363.30709@mcleodusa.net...
> This code works:
>
> alias void delegate(int) t_func;
>
> class Foo
> {
>    t_func func1;
>
>    void dothis()
>    {
>      if (func1) func1(4); else
>        printf("func1 not assigned\n");
>    }
>
>    void func(int num) { printf("num = %d\n", num); }
> }
>
> int main(char[][] args)
> {
>    Foo a = new Foo;
>    a.dothis();
>    a.func1 = &a.func;
>    a.dothis();
>    return 0;
> }
>
> Result:  func1 not assigned
>           num = 4
>
> However, if I move the func declaration to outside of the class, the
> line "a.func1 = &func" produces the error message:  toelem: cannot cast
> from void(*)(int num) to void delegate(int).
> If I then change the t_func declaration from alias to typedef then I
> get:  cannot implicitly convert void(*)(int num) to t_func.
> If I go back to the original working code and change alias to typedef
> then I get:  Internal error: e21r.c 78
>
> What are the reasons for these error messages?  It seems to me that all of these senarios should work.
>
> Thanks,
>
> Paul
>