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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Bounded String question
Date: Wed, 11 Nov 2015 10:36:06 -0700
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Date: 2015-11-11T10:36:06-07:00
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On 11/11/2015 08:34 AM, Bob Duff wrote:
> "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org> writes:
> 
>> On 11/10/2015 05:48 PM, Bob Duff wrote:
>>>
>>> I suggest rolling your own.  No need for generics.
>>>
>>>    type Bounded_String (Max_Length : Natural := ...) is limited record
>>>       Length : Natural := 0;
>>>       Chars  : String (1 .. Max_Length);
>>>    end record;
>>
>> Except that using Natural for Max_Length results in GNAT allocating Integer'Last
>> characters for Chars, which is unlikely to fit on the stack.
> 
> No, the type is limited, so GNAT will allocate space for Max_Length
> characters, not Natural'Last characters.

I missed the "limited" and concentrated on the default for the discriminant. It
does mean that assignment becomes a bit messy, though.

-- 
Jeff Carter
"When Roman engineers built a bridge, they had to stand under it
while the first legion marched across. If programmers today
worked under similar ground rules, they might well find
themselves getting much more interested in Ada!"
Robert Dewar
62