How to override function?

[Zarathustra]

grauzone Wrote:

> Zarathustra wrote:
> > I would like to know, how to override function if subclass and super class are located in the same package and different modules.
> > 
> > For instance when they are in the same module:
> > //___________________________________
> > module main;
> > class Foo{
> > 
> >   this(){
> >     proc();
> >   }
> >   
> >   void proc(){
> >     writefln("Foo");
> >   }
> > }
> > 
> > class Bar : Foo{
> >   override void proc(){
> >     writefln("Bar");
> >   }
> > }
> > 
> > void main(){
> >   new Bar;
> > }
> > //___________________________________
> > the result is "Bar" so it's great, but:
> > 
> > //___________________________________
> > module pack.foo;
> > 
> > class Foo{
> > 
> >   this(){
> >     proc();
> >   }
> >   
> >   package void proc(){ // without 'package' it works well
> >     writefln("Foo");
> >   }
> > }
> > 
> > //___________________________________
> > module pack.bar;
> > 
> > class Bar : Foo{
> >   package override void proc(){ // without 'package' it works well
> >     writefln("Bar");
> >   }
> > }
> > //___________________________________
> > module main;
> > void main(){
> >   new Bar;
> > }
> > //___________________________________
> > the result is "Foo" so it's unexpected to me.
> 
> It's a bug. package functions are never virtual, and the "override" 
> attribute is just ignored. Same with private. Welcome to D.

In my opinion 'private' shouldn't be virtual if sub- and sup- classes are located in different modules. Also if I have a global private function in the first module and the global function at the same name in the second module there shouldn't be conflict.

In C++ everything which is in 'source file', but not in 'header' it is nothing less than 'private'. I D it is impossible to 'hide' global function inside module (in my opinion it is bug).

I resolved 'package' function overriding problem as follow:

class Foo{
  package void delegate() proc;
  private void _proc(){ ... }
  this(){
    proc = &_proc;
  }
  package this(void delegete() o_proc){
    proc = o_proc;
  }
}

class Bar : Foo{
  private void _proc(){ ... }
  this(){
    super(&_proc);
  }
}