Re: beginner ada generic fonction

[Simon Wright <simon@pushface.org>]

ametayer98@hotmail.com (annabelle) writes:

> The thing is, I was given the following spec and I cant change it.
> I've GOT to use it as it is.
> 
> I can make the "LaCle" function to work but now I have trouble with
> the "<" function...
> 
> I would love to have an example of how I call this "<" in my ADB file
> and how do  I define this function in my ADA project...
> 
> I know I am a pain in the neck !!! I have great difficulty with the
> concept but I know I CAN understand eventually !!!
> 
> GENERIC
>   TYPE Type_Element IS Private;                               -- Type
> de l'enregistrement a gerer
>   TYPE Type_Cle IS Private;                                   -- Type
> de la cle de l'enregistrement
>   WITH Function LaCle (mon_item : Type_Element) Return Type_Cle;  --
> Fonction qui retourne la valeur de la cle
>   WITH Function "<"  (Gauche,Droite : Type_Cle) Return Boolean;  --
> Importation de l'operateur < pour comparer des cles

Removing the comments so that it fits on a line,

GENERIC
  TYPE Type_Element IS Private;
  TYPE Type_Cle IS Private;
  WITH Function LaCle (mon_item : Type_Element) Return Type_Cle;
  WITH Function "<"  (Gauche,Droite : Type_Cle) Return Boolean;

there is something missing, namely what it is that is is to be generic.

The next line must start with PACKAGE, PROCEDURE or FUNCTION.

The idea is that *you* supply a function LaCle and a function "<"
which work as indicated with a Type_Cle (whatever that is), and then
the *instantiation of the generic* calls the functions to do what it
needs to do ...