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From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: Array Help?
Date: Fri, 9 Mar 2012 15:10:39 -0600
Date: 2012-03-09T15:10:39-06:00	[thread overview]
Message-ID: <jjdrkl$q8l$1@munin.nbi.dk> (raw)
In-Reply-To: Pine.LNX.4.64.1203090923440.19986@medsec1.medien.uni-weimar.de

<stefan-lucks@see-the.signature> wrote in message 
news:Pine.LNX.4.64.1203090923440.19986@medsec1.medien.uni-weimar.de...
> On Thu, 8 Mar 2012, Randy Brukardt wrote:
...
> Sorry for using anonymous arrays. I hardly ever do this in real
> code. Please change the above code to
>
>  generic
>     type Element_Type is (<>);
>     type Collection_Type is array(generic Positive range <>) of 
> Element_Type;
>     with function "<"(Left, Right : Element_Type) return Boolean is <>;
>  function Sort(Items : Collection_Type) return Collection_Type;
>
> The issue is the same:
>
>> > Sort(X) should be callable if the index type of X is any discrete type,
>> > except when the index type is too large (i.e., X has more than
>> > Positive'Last elements).

Which as I said doesn't make sense: Positive is numeric; if you want any 
discrete type for the index you have to say so:

 generic
     type Element_Type is (<>); -- Really ought to be "is private".
     type Index_Type is (<>);
     type Collection_Type is array(Index_Type range <>) of Element_Type;
     with function "<"(Left, Right : Element_Type) return Boolean is <>;
 function Sort(Items : Collection_Type) return Collection_Type;

This works now (and has since Ada 83!), so I fail to see exactly what your 
proposal gains (other than a bit less typing, and Ada have never been about 
saving typing).

                                 Randy.





  reply	other threads:[~2012-03-09 21:10 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-28 20:15 Array Help? Will
2012-02-28 20:47 ` Ludovic Brenta
2012-02-28 22:11   ` Simon Wright
2012-02-28 23:09     ` Will
2012-02-29  0:24   ` Adam Beneschan
2012-02-28 20:50 ` Gautier write-only
2012-02-28 21:33 ` Simon Wright
2012-02-29  0:27   ` Adam Beneschan
2012-02-29  8:00     ` Simon Wright
2012-02-29  8:48       ` Simon Wright
2012-02-29  0:22 ` Adam Beneschan
2012-02-29 16:09   ` Robert A Duff
2012-02-29 16:50     ` Ludovic Brenta
2012-02-29 18:24       ` Robert A Duff
2012-02-29 19:45         ` stefan-lucks
2012-02-29 20:45           ` Jeffrey Carter
2012-02-29 21:27             ` stefan-lucks
2012-02-29 23:06           ` Robert A Duff
2012-03-02 13:45             ` stefan-lucks
2012-03-07 23:58             ` Randy Brukardt
2012-03-08 11:20               ` stefan-lucks
2012-03-09  2:02                 ` Randy Brukardt
2012-03-09  8:48                   ` stefan-lucks
2012-03-09 21:10                     ` Randy Brukardt [this message]
2012-03-15  2:55                     ` BrianG
2012-03-15  7:46                       ` stefan-lucks
2012-02-29 20:07         ` Dmitry A. Kazakov
2012-02-29 23:15           ` Robert A Duff
2012-03-01  8:54             ` Dmitry A. Kazakov
2012-03-01 14:06               ` Robert A Duff
2012-02-29 20:47         ` Simon Wright
2012-02-29 22:23           ` Robert A Duff
2012-02-29 23:27             ` Robert A Duff
2012-03-01  0:53               ` Adam Beneschan
2012-03-01  7:16               ` Ludovic Brenta
2012-03-01 14:03                 ` Robert A Duff
2012-03-08  0:11                   ` Randy Brukardt
2012-03-08  0:08               ` Randy Brukardt
2012-02-29 23:30             ` Simon Wright
2012-02-29 18:35     ` Jeffrey Carter
2012-02-29 22:59       ` Robert A Duff
2012-02-29 23:51         ` Jeffrey Carter
2012-03-01  3:03           ` Robert A Duff
2012-02-29 20:40     ` Adam Beneschan
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