From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,aa7f494bf30adbc7
X-Google-Attributes: gid103376,public
Path: g2news1.google.com!postnews2.google.com!not-for-mail
From: mheaney@on2.com (Matthew Heaney)
Newsgroups: comp.lang.ada
Subject: Re: [newbie] simple(?) data structures
Date: 23 Jun 2004 17:09:40 -0700
Organization: http://groups.google.com
Message-ID: <1ec946d1.0406231609.11a051cb@posting.google.com>
References: <2j1e30Fsrg8vU1@uni-berlin.de>
NNTP-Posting-Host: 66.162.65.162
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
X-Trace: posting.google.com 1088035781 31425 127.0.0.1 (24 Jun 2004 00:09:41
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Thu, 24 Jun 2004 00:09:41 +0000 (UTC)
Xref: g2news1.google.com comp.lang.ada:1840
Date: 2004-06-23T17:09:40-07:00
List-Id: <comp.lang.ada>

Roland Illig <roland.illig@gmx.de> wrote in message news:<2j1e30Fsrg8vU1@uni-berlin.de>...
> Hi,
> 
> I'm doing my first steps with Ada. I tried to model a Go board and 
> failed. In Java/C++, I would do it like this:
> 
> enum Stone { Empty, Black, White };
> 
> class Go_Board {
>      private Stone[][] data;
> 
>      public Go_Board(int size) {
>          data = new Stone[size][size];
>      }
>      public int getWidth() {
>          return data[0].length;
>      }
>      public int getHeight() {
>          return data.length;
>      }
>      public Stone getStone(int x, int y) {
>          return data[y][x];
>      }
> }
> /* EOF */
> 
> How can I do this in Ada? I already tried something with packages and 
> generics, but that did not look nice. But I want it to look nice and Adaish.

You didn't need generics for the Java program, so therefore you don't
need them for the Ada program, either:

package Go_Boards is

   type Board_Type (Size : Positive) is private;

   type Stone_Type is (Empty, Black, White);

   function Stone (Board : Board_Type) return Stone_Type;

   --function Width (B : BT) return Positive;  --same as B.Size?

private

   type Data_Type is 
     array (Positive range <>, Positive range <>) of Stone_Type;

   type Board_Type (Size : Positive) is record
      Data : Data_Type (1 .. Size, 1 .. Size);
   end record;

end Go_Boards;


I haven't tried compiling this, but I think it should work.