From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00
	autolearn=unavailable autolearn_force=no version=3.4.4
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail
From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Generic formal type with 'Image
Date: Wed, 6 Jun 2018 17:34:58 +0200
Organization: Also freenews.netfront.net; news.tornevall.net;
 news.eternal-september.org
Message-ID: <pf8uv3$tr4$1@dont-email.me>
References: <pf8m2r$vj$1@dont-email.me>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Wed, 6 Jun 2018 15:34:59 -0000 (UTC)
Injection-Info: reader02.eternal-september.org;
 posting-host="23e84d1c0628dd789a0f101917042218";
	logging-data="30564"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX193+2b1piUDsZ4lju1pmz6HSvgSyuBlxUk="
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.8.0
Cancel-Lock: sha1:AD5imR1DbX6Gd0jJatnye6kPPnI=
In-Reply-To: <pf8m2r$vj$1@dont-email.me>
Content-Language: en-US
Xref: reader02.eternal-september.org comp.lang.ada:52958
Date: 2018-06-06T17:34:58+02:00
List-Id: <comp.lang.ada>

On 06/06/2018 03:03 PM, Alejandro R. Mosteo wrote:
> I'm pretty sure the answer is "no", but just in case:

You're right; as things are now, you can't do it. You have to do

generic -- Name
     type Printable is private;
     with function Image (P : Printable) return String is <>;
package Name is
    procedure Proc (P : in Printable);
    function Func (P : Printable) return Boolean;
end Name;

You can then, if you like, do things like

generic -- Name_Discrete
    type Discrete is (<>);
package Name_Discrete is
    procedure Proc (P : in Discrete);
    function Func (P : Discrete) return Boolean;
end Name_Discrete;

with Name;
package body Name_Discrete is
    package Internal is new Name
       (Printable => Discrete, Image => Discrete'Image);

    procedure Proc (P : in Discrete) renames Internal.Proc;
    function Func (P : Discrete) return Boolean renames Internal.Func;
end Name_Discrete;

-- 
Jeff Carter
"You me on the head hitted."
Never Give a Sucker an Even Break
108