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From: aek@vib.usr.pu.ru (Alexander Kopilovitch)
Newsgroups: comp.lang.ada
Subject: Re: += in ada
Date: 7 Oct 2003 11:28:54 -0700
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Date: 2003-10-07T11:28:54-07:00
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Lutz Donnerhacke wrote:
>  declare
>     a : Typ renames X(b(i).all + 7);
>  begin
>     a := a + 2/a;
>  end;
>
>  is legal Ada and a common idiom.
>
>  ...
>
>  So I have to conlude, that the whole "idem" Idiom is useless at all.

But "idem" require neither identifier nor declare-begin-end, and it is purely
local. Sometimes it is better to use renaming, but far from always - there are
enough cases where "idem" is better... and more natural. Use of renaming here
is just a middle of the spectre of solutions, where one edge is a function
returning access (which is generally more burdensome in Ada than in C) and
another edge is "idem".



Alexander Kopilovitch                      aek@vib.usr.pu.ru
Saint-Petersburg
Russia