Re: 'Read for pointers

["Pat Rogers" <progers@NOclasswideSPAM.com>]

"Ted Dennison" <dennison@telepath.com> wrote in message
news:8lpeog$gvc$1@nnrp1.deja.com...
> In article <lZIf5.190$wE4.35361@nnrp3.sbc.net>,
>   "Pat Rogers" <progers@NOclasswideSPAM.com> wrote:
>
> > "Ted Dennison" <dennison@telepath.com> wrote in message
> > news:8lndgv$1om$1@nnrp1.deja.com...
> > > The problem is that Item is an *out* parameter. That means I
won't
> > > have acces to the pointer's old value inside Read. There's no
way I
>
> > Further to my previous post, to the effect that one can indeed
read
> > mode out parameters: the access value of the actual is copied into
the
> > formal, so you get a meaningful value coming in even though the
mode
> > is out. See RM 6.4.1{12,13}
>
> Wow. That's one I would not have guessed. So there's effectively no
> difference between "out" and "in out" for access types, composite
types
> with discriminants, or record types with default field values? %-}

As long as the latter two happen to be passed by copy (access types
always are).

--
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