Access in parameters

Access in parameters

[Sandro Binetti]

 Why is this correct?

  type T_XXX is access all integer;

  procedure PP(x:in t_xxx) is
  begin
    x.all:=10; -- ????
  end pp;

Can an in-access-parameter be modified inside a procedure?

Thank you everybody.

--
Ciao, Sandro


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Re: Access in parameters

[lafortg]

You're not modifying the x in parameter, your're modifying the integer
accessed via
x.

Sandro Binetti wrote:

>  Why is this correct?
>
>   type T_XXX is access all integer;
>
>   procedure PP(x:in t_xxx) is
>   begin
>     x.all:=10; -- ????
>   end pp;
>
> Can an in-access-parameter be modified inside a procedure?
>
> Thank you everybody.
>
> --
> Ciao, Sandro
>
> Sent via Deja.com
> http://www.deja.com/

--

George Lafortune
Raytheon Electronic Systems
Sudbury, Ma
e-mail: george_n_lafortune@res.raytheon.com
phone : 978-440-1423

Re: Access in parameters

[n_brunot]

The access parameter is not modified.
x keep the same value.
Only the pointed value x.all is changed.

In article <934cbk$9ta$1@nnrp1.deja.com>,
  Sandro Binetti <sandrobinetti@my-deja.com> wrote:
>  Why is this correct?
>
>   type T_XXX is access all integer;
>
>   procedure PP(x:in t_xxx) is
>   begin
>     x.all:=10; -- ????
>   end pp;
>
> Can an in-access-parameter be modified inside a procedure?
>
> Thank you everybody.
>
> --
> Ciao, Sandro
>
> Sent via Deja.com
> http://www.deja.com/
>


Sent via Deja.com
http://www.deja.com/

Re: Access in parameters

[Florian Weimer]

Sandro Binetti <sandrobinetti@my-deja.com> writes:

>   type T_XXX is access all integer;
> 
>   procedure PP(x:in t_xxx) is
>   begin
>     x.all:=10; -- ????
>   end pp;
> 
> Can an in-access-parameter be modified inside a procedure?

In this case, you don't modify the parameter x, but the object given
x.all.

Re: Access in parameters

[Ehud Lamm]

Compare to the definition here:

package You_cant_change_it is

   type Int_P is access constant Integer;

   X:constant Int_P;

   procedure p;

private
   Y:aliased integer:=10;
   X:constant Int_P:=Y'access;

end;

(The body however  can offer surprises:
package body You_cant_change_it is

   -------
   -- p --
   -------

   procedure p is
   begin
      Y:=Y+1;
   end p;

end You_cant_change_it;
)


--
Ehud Lamm   mslamm@mscc.huji.ac.il