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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: [Newbie] doubly constrained array, dumb question
Date: Mon, 26 Feb 2018 22:52:08 +0200
Organization: Tidorum Ltd
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Date: 2018-02-26T22:52:08+02:00
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On 18-02-26 18:26 , Mehdi Saada wrote:
> Hello.
>
> I would like an constrained String subtype with narrower bounds that Positive'Range.
> How can I do something like:
> subtype Possible_Length is NATURAL range 1..80;
> subtype T_Line is String (Possible_Length range <>);
> ? I know "range <>" isn't included in the definition of "range_constraint". How can I express the same thing.
> So that I can get after, a dynamic string with:
> A: access T_LINE := new T_LINE'("BLABLABLA"); while checking for its range.

I think the closest you can come is to define your own string type such 
that it can be type-converted to/from String, for example like this:

    subtype Small_Positive is Positive range 1 .. 20;

    type Short_String is array (Small_Positive range <>) of Character;

    SS : constant Short_String := "abc";

    S : constant String := String (SS);

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
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