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Newsgroups: comp.lang.ada
Date: Thu, 31 Oct 2019 02:30:29 -0700 (PDT)
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Subject: Re: gnat.string_split , howto manipulate slice numbers
From: joakimds@kth.se
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Xref: reader01.eternal-september.org comp.lang.ada:57396
Date: 2019-10-31T02:30:29-07:00
List-Id: <comp.lang.ada>

> >
> > Another reason is to distinguish index/key from position. When both
> > are subtypes of integer some bugs may slip through, e.g.
> >
> >    A (A'Length - 1)
> >
> > This is broken code, but the compiler cannot detect it.
> 
> How is it broken?
> 

The index should be an index from A'First to A'Last and using A'Length does not guarantee A'Length - 1 being a valid index. Hmm... how to fix it in the best possible way? Or just accept it being an edge case Ada does not detect at compile-time?

Best regards,
Joakim