Re: troubles learning OOP: expected type "Parent.Some_Child", found type Parent'Class

[Mehdi Saada <00120260a@gmail.com>]

the components are all enumeration types of one character, except for T_TOKEN_OPERANDE.OPERANDE who's an INTEGER.
Ahhh... The trick is to encapsulate the components of different types into tagged types, so that they can be grouped together into a class, and so GET_ELEM can be dispatched. That's awfully artifical. Unfortunately, I must keep with the current design,
with things like
type T_TOKEN is abstract tagged null record;
type T_TOKEN_OPERANDE is new T_TOKEN with record
    OPERANDE: INTEGER;
end record;
Besides, I still would need to access the actual inner component of Something, not only OPERANDE_SOMETHING. Even I'm wrong I can't apply that anyway.

I can't believe T_TOKEN'class is as useless... well, in a sense, since the program doesn't know the actual type of TOKEN but only that it's a child of T_TOKEN, no wonder there's some limitations. But I'm surprised there's no mechanism in the language, to tell the program: HEY there ! I'm sure it's T_TOKEN_OPERANDE, so now consider TOKEN as such and let me reach it's OPERANDE component.