[fpc-pascal]Linked List/ pointers/ casting/ OOP Question

[Ron Weidner]

> At first glance, this should read 
>   PwidgetSomething(PCurWidget^.widget)^.meta =
> 'ENTITY'
> because widget is an untyped pointer ?
> 
> And the same for the other line ?
> 
> Michael.

Thanks Michael.  Actually widget is a typed pointer
but the problem I was trying to solve is that widget
could be one of two different types.  I think I solved
my problem with the following code, but I will need
write a test program to be sure.  It compiles so I
must be getting close.  :)

procedure TWidgetContainer.RenderWidgets();
var 
entity:PWidgetEntity;
container:PWidgetContainer;
base:PWidget;
begin
	MoveFirstWidget();
	while (PCurWidget^.next <> nil) do
	begin
		base:=PCurWidget^.widget; // cast the pointer to a
widget pointer
		if (base^.meta = 'ENTITY') then
		begin
			PCurWidget^.widget:=PCurWidget^.widget;
			entity:=PCurWidget^.widget;
			entity^.Render();
		end
		else
		begin
			container:=PCurWidget^.widget;
			container^.Render();
		end;
		PCurWidget:=PCurWidget^.next;
		dispose(PHeadWidget);
		PHeadWidget:=PCurWidget;		
	end;
end;


Ron_W


		
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