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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: strange length check error
Date: Thu, 18 Jan 2018 11:12:30 +0000
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Date: 2018-01-18T11:12:30+00:00
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"Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org> writes:

> On 01/17/2018 02:41 PM, Simon Wright wrote:
>>
>>     return
>>       (LENGTH(LEFT) + 1,
>>        LEFT.DATA(1..LENGTH(LEFT))
>>          & RIGHT
>>          & LEFT.DATA((LENGTH(LEFT) + 1)..MAX_LENGTH));
>
> I think the last part should be Left.Data (Left.Length + 1
> .. Max_Length - 1) or (Left.Length + 2 .. Max_Length). I guess it
> doesn't matter what you put in those unused positions; you could also
> have (Left.Length + 2 .. Max_Length => <>).

Should have been (Left.Length + 2 .. Max_Length). That'll teach me not
to post code without testing it ..

> I'd probably have written
>
>    Result : Bounded_String;
> begin -- "&"
>    Result.Length := Left.Length + 1;
>    Result.Data (1 .. Result.Length) := Left (1 .. Left.Length) & Right;
>
>    return Result;

There was a check in the original that the input wasn't already at its
max length. That aside, agreed.