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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
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Subject: Re: Lower bounds of Strings
Date: Fri, 15 Jan 2021 16:12:37 +0100
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On 1/15/21 2:56 PM, Stephen Davies wrote:
> On Friday, 15 January 2021 at 11:48:27 UTC, Jeffrey R. Carter wrote:
>> type String_Base is array (Positive range <>) of Character;
>> subtype String is String_Base (Positive range 1 .. <>);
> 
> I wish it had been this way since the beginning. That way, in those
> rare instances where code is really using the variable lower-bound,
> the use of String_Base would the intention clear. Alas, making that
> change now would break that code.

We have that now, with the substitutions

String_Base => String
String      => type S1 (Length : Natural is record
                   Value : String (1 .. Length);
                end record;
             or
                subtype S1 is String with Dynamic_Predicate => S1'First = 1;

-- 
Jeff Carter
"[I]t is more important to make the purpose
of the code unmistakable than to display
virtuosity. Even storage requirements and
execution time are unimportant by
comparison ..."
Elements of Programming Style
184