Re: Q: discrete_subtype_definition: static only cases?

["Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>]

On 6/7/20 2:13 PM, gautier_niouzes@hotmail.com wrote:
>> No. The basic principle is that types are static (they determine the
>> underlying representation) and subtypes are dynamic.
> 
> Well, there are obviously exceptions to that basic principle:
> 
> procedure SD2 is
> begin
>    for I in 1 .. 3 loop
>      declare
>        type T is array (1 .. I) of Integer;  --  I is a variable
>        B: T;
>      begin
>        null;
>      end;
>    end loop;
> end;

Conceptually, this declaration is equivalent to

type /anon/ is array (Integer range <>) of Integer;
subtype T is /anon/ (1 .. I);

So the (anonymous) type is static, but the (first-named) subtype is not.

-- 
Jeff Carter
"How'd you like to hide the egg and gurgitate
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