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From: "J-P. Rosen" <rosen@adalog.fr>
Newsgroups: comp.lang.ada
Subject: Re: Possible to recover default value of scalar type?
Date: Tue, 15 Dec 2020 10:07:02 +0100
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Le 15/12/2020 à 08:23, Dmitry A. Kazakov a écrit :
>> Not applicable if your variable is used in a loop:
>>
>>     V : Integer;
>> begin
>>     loop
>>        Get (V);
>>        exit when V =0;
>>        -- do something with V
>>     end loop;
>>
>> Clearly, initializing V makes no sense.
> 
>    loop
>       declare
>          V : constant Integer := Get;
>       begin
>          exit when V = 0;
>          -- do something with V
>       end;
>    end loop;
> 
Well, you can push anything in a function, but it's not always
clear/readable/simpler...

> It is related to another long standing issue with returning values
> (multiple values) from functions and functions with in out parameters
> (resolved recently).
> 
> Returning to Simon's argument about detecting uninitialized variables.
> It would not apply to your example.
> 
>    V : Integer := <>;  -- Invented syntax for explicit lack of
>                        -- initialization
> begin
>    loop
>       Get (V);
>       exit when V = 0;
>       -- do something with V
>    end loop;
That would make more sense: make initialization required, and say so if
you don't care.

-- 
J-P. Rosen
Adalog
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