Got it!!
It's a really good exercise to understand pointers and recursivity!
Thanks.

procedure Insert_iteratif(E : in Element; L : in out Liste) is

Aux : Liste := L;

Z : Liste;

begin

                if (L = null) then

            L := new Maillon'(E,null);

                else

                                while (Aux /= null) loop

                                            if (Aux.all.valeur > E) then

                      z.all.suivant := new Maillon'(E,Aux);

                                                            exit;

                                             elsif (Aux.all.suivant = null)
then

                       z.all.suivant := new Maillon'(E,null);

                                                              exit;

                                             end if;


           z := Aux ;

                              Aux := Aux.all.suivant;


                            end loop;

                end if;


end Insert_iteratif;

"Simon Wright" <simon@pushface.org> a �crit dans le message de
news:x7vfzngg39y.fsf@smaug.pushface.org...
> "Zeg" <zeg.nospam@9online.fr> writes:
>
> > procedure Insert_iteratif(E : in Element; L : in out Liste) is
> > Aux : Liste := L;
> > Z : Liste := null;
>
> You don't need to initialize access variables, they are automatically
> set to null for you
>
> > begin
> >       if (Aux = null) then
> >          Aux := new Maillon'(E,null);
>
> L was empty, so what is it pointing to now? Should you have altered it?
>
> >       else
> >          while  (Aux /= null) loop
> >               if (Aux.all.valeur > E) then
> >                   L := new Maillon'(E,Aux);
>
> What has happened to all the previous elements in the list? (that L
> used to be pointing to)
>
> >                   exit;
> >             elsif (Aux.all.suivant = null) then
> >                   L:= new Maillon'(E,null);
>
> What has happened to all the previous elements in the list?
>
> >                   exit;
> >             end if;
> >             z := Aux ;
>
> What is Z for? You don't read it anywhere
>
> >             Aux := Aux.all.suivant;
> >          end loop;
> >      end if;
> >
> > end Insert_iteratif;
>
> It might help you to draw a picture of Maillons linked into a Liste,
> and how you want a new Maillon to be linked in.