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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: strange length check error
Date: Wed, 17 Jan 2018 13:41:58 +0000
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Date: 2018-01-17T13:41:58+00:00
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AdaMagica <christ-usch.grein@t-online.de> writes:

> Am Mittwoch, 17. Januar 2018 13:13:49 UTC+1 schrieb Mehdi Saada:
>> I get it, it's ugly, inefficient, wrong, I KNOW, but it's not mine,
>> and I can't affor rewriting *every* piece of code that come along
>> the exercices.
>> Well, I could replace the actual
>> type BOUNDED_STRING is record
>>     LENGTH: NATURAL := 0;
>>     DATA: STRING (1 .. 80); <---- I guess *you* forgot this or else
>> it's illegal
>> end record;
>
> Then of course this will raise an exception:
> return (LENGTH(LEFT) + 1, LEFT.DATA(1..LENGTH(LEFT)) & RIGHT);
> since
> LEFT.DATA(1..LENGTH(LEFT)) & RIGHT is shorter than 80.
>
> Who is the *teacher*?

I'm guessing that this is a generic, with parameter MAX_LENGTH, so maybe

   type BOUNDED_STRING is record
      LENGTH: NATURAL := 0;
      DATA: STRING (1 .. MAX_LENGTH);
   end record;

& then this should be OK

   return
     (LENGTH(LEFT) + 1,
      LEFT.DATA(1..LENGTH(LEFT))
        & RIGHT
        & LEFT.DATA((LENGTH(LEFT) + 1)..MAX_LENGTH));