From: "Nick Roberts" <Nick.Roberts@dial.pipex.com>
Subject: Re: [Q] Returning Strings From A Function
Date: 1997/04/08
Date: 1997-04-08T00:00:00+00:00 [thread overview]
Message-ID: <01bc43b8$a4c441a0$09f682c1@xhv46.dial.pipex.com> (raw)
In-Reply-To: E89sJq.62y@world.std.com
Robert A Duff <bobduff@world.std.com> wrote in article
<E89sJq.62y@world.std.com>...
> In article <01bc42af$e32e3ea0$90f482c1@xhv46.dial.pipex.com>,
> Nick Roberts <Nick.Roberts@dial.pipex.com> wrote:
> > FS: Filename_String := ""; -- unconstrained type, so must be
initialised
>
> FS is forever constrained to length zero.
>
> > FS := Text_IO.Name(F); -- constraint error raised if longer than 12
>
> No, this will raise C_E, unless the name is of length zero.
>
> Ada's built-in arrays cannot change size.
Argh! The embarrassment! Sudden brainstorm, Bob (my excuse being that I am
using a lot of different languages at the moment (pretty feeble, eh?)).
Anyway, what I _should_ have written was this...
declare
F: Text_IO.File_Type;
...
type Filename_String is array (1..12 range <>) of Character;
type Filename_Ref is access Filename_String;
...
S: Filename_Ref;
...
begin
...
S := new Filename_String'(Text_IO.Name(F)); -- constraint error raised
if name longer than 12 chars
...
Text_IO.Put("Name of file is: "+String(S.all)); -- note the need to
dereference and convert
...
end;
John: I hope I did not end up confusing you. Many apologies. The above will
actually work, and will hopefully be a relatively simple solution to your
problem.
Nick.
next prev parent reply other threads:[~1997-04-08 0:00 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
1997-04-04 0:00 [Q] Returning Strings From A Function John McCabe
1997-04-04 0:00 ` Joakim Olsson
1997-04-05 0:00 ` John McCabe
1997-04-05 0:00 ` Robert Dewar
1997-04-06 0:00 ` John McCabe
1997-04-06 0:00 ` Robert Dewar
1997-04-06 0:00 ` Nick Roberts
1997-04-07 0:00 ` Robert A Duff
1997-04-08 0:00 ` Nick Roberts [this message]
1997-04-07 0:00 ` Matthew Heaney
1997-04-06 0:00 ` Matthew Heaney
1997-04-05 0:00 ` Robert A Duff
1997-04-05 0:00 ` johnherro
1997-04-05 0:00 ` Mark & Zurima McKinney
1997-04-07 0:00 ` Jon S Anthony
1997-04-07 0:00 ` johnherro
1997-04-07 0:00 ` johnherro
1997-04-07 0:00 ` Robert Dewar
1997-04-08 0:00 ` Jeff Carter
1997-04-09 0:00 ` Looking for an Ada SCIENTIFIC UNITS checking package Ron House
1997-04-05 0:00 ` [Q] Returning Strings From A Function Robert Dewar
1997-04-06 0:00 ` John McCabe
1997-04-06 0:00 ` Robert Dewar
1997-04-06 0:00 ` John McCabe
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