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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 22:10:08 +0100
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On 1/15/21 6:22 PM, Stephen Davies wrote:
> On Friday, 15 January 2021 at 15:12:39 UTC, Jeffrey R. Carter wrote:
>> subtype S1 is String with Dynamic_Predicate => S1'First = 1;
> Like I said before, I want Sliding, not bounds checking. I guess
> most Usenet discussion eventually end up going around in circles.

Then you would probably prefer the record version. Neither is perfect, but both, 
with appropriate conversion functions, give you the effect you want with current 
Ada.

-- 
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