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Newsgroups: comp.lang.ada
Subject: Re: Bitmanipulation in Ada
From: Bernd.Specht@gmx.com (Bernd Specht)
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Date: 19 Aug 2004 17:44:05 GMT
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Jeffrey Carter <spam@spam.com> wrote in news:wSSUc.27249$9Y6.977
@newsread1.news.pas.earthlink.net:

> Bernd Specht wrote:
> That may be what you want. What a software engineer wants is the 
> clearest software that meets the requirements. Unchecked_Conversion will 
> almost always provide this.

Sure.

 
> In many cases, Unchecked_Conversion will generate no code, and need not 
> involve an assignment. In well designed software, the part(s) of the 
> software that deals with values as an integer and those that deal with 
> them as bit arrays will be kept separate. So you do something like:

Always? What do you think about bitscrambling software which has to treat 
data alternating as bitvector and as integer value in a loop like this (not 
exeactly this for securitity reasons):

...
loop
  declare
    x : boolean;
  begin
     x := b(k);
     b(k) := b(32 - k);
     b (32 - k) := x;
     I := I * prime1 mod prime2;
  end;
end loop;


Can you find an equivalent algorithm where you can separate the bit-ops and 
the integer-ops?