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From: "Pat Rogers" <progers@NOclasswideSPAM.com>
Subject: Re: Why parameter passing by copy?
Date: 2000/05/27
Date: 2000-05-27T00:00:00+00:00	[thread overview]
Message-ID: <IKUX4.1974$Rn4.185168@nnrp3.sbc.net> (raw)
In-Reply-To: dale-277623.23001027052000@news.rmit.edu.au

"Dale Stanbrough" <dale@cs.rmit.edu.au> wrote in message
news:dale-277623.23001027052000@news.rmit.edu.au...
> Ada requires that scalars be passed by copy. I was under the
impression
> that this was chosen because it was faster, but i've never seen a
> rational argument for this from the Ada83 perspective of computer
> hardware, nor whether such arguments still hold true for modern
> processors.
>
> Can anyone shed any light on this?

Passing things by copy precludes aliasing, which can lead to nasty
surprises.  For scalars there is no speed penalty so the language
mandates it for the safety aspect.


--
Pat Rogers                            Consulting and Training in:
http://www.classwide.com      Deadline Schedulability Analysis
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  parent reply	other threads:[~2000-05-27  0:00 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2000-05-27  0:00 Why parameter passing by copy? Dale Stanbrough
2000-05-27  0:00 ` Thierry Lelegard
2000-05-27  0:00 ` Pat Rogers [this message]
2000-05-28  0:00   ` Robert Dewar
2000-05-27  0:00 ` Robert Dewar
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