Re: Ada Singleton Pattern

[Luca Stasio <stasio2000@tin.it>]

Dmitry A. Kazakov ha scritto:

> On Mon, 13 Sep 2004 15:04:27 GMT, Luca Stasio wrote:
> 
> 
>>Hi, there is a way to implement the Singleton Pattern in Ada?
>>There are some examples out there?
>>Thanx.
> 
> 
> package Foo is
>    type Singleton (<>) is limited private;
>    ... -- Public interface subroutines
> 
>    The_Only_One : constant Singleton; -- The value
> private
>    type Singleton is new Integer; -- Any implementation you want
>    The_Only_One : constant Singleton := 5;
> 
> The public view of Singleton is unconstrained and limited, which prevents
> it from either being copied or declaring new objects of this type.
> 
thanx a lot ;o)