Re: Hiding the value of Constants

["Hibou57 (Yannick Duchêne)" <yannick_duchene@yahoo.fr>]

On 7 juil, 11:41, Georg Bauhaus <rm.dash-bauh...@futureapps.de> wrote:
> I'm assuming you do not want the value to be
> visible neither in the private part nor in the
> public part of the package specification?
>
> Use a function then, and make the package pure,
> if possible:
>
> package P is
>
>   pragma pure;
>
>   type Thing is ...;
>
>   function My_Constant return Thing;
>
>   pragma Inline(My_constant);
>
> end P;
>
> Chances are that the compiler might be able to
> act as if My_Constant was a simple constant.

As some one are talking about Funny_Types, here is a funny thing
(thinking about it when I saw this solution) : Ada defines enumeration
contants as parameterless functions (just like you propose for these
constants).

RM 2005 3.5.1 says:
> 6 {enumeration literal} Each enumeration_literal_specification is the
> explicit declaration of the corresponding enumeration literal: it
> declares a parameterless function, whose defining name is the
> defining_identifier or defining_character_literal, and whose result
> type is the enumeration type.

But this is with some restrictions (ex. one may not get the adress of
such a function)

This has some conscequences on the name resolution of an enumeration
literal reference vs of a constant reference. Sometimes I wish both
will be one day handled the same (enumeration literals and constants)