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,FREEMAIL_FROM
	autolearn=ham autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,912597791e813f68
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2003-01-08 01:01:08 PST
Path: archiver1.google.com!postnews1.google.com!not-for-mail
From: gautier_niouzes@hotmail.com (Gautier)
Newsgroups: comp.lang.ada
Subject: Re: advantages or disadvantages of ADA over pascal or modula
Date: 8 Jan 2003 01:01:08 -0800
Organization: http://groups.google.com/
Message-ID: <17cd177c.0301080101.3f826bab@posting.google.com>
References: <av4c0m$8a4$06$1@news.t-online.com>
 <b1ire-081.ln1@martinkl.dialup.fu-berlin.de>
NNTP-Posting-Host: 213.173.163.2
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit
X-Trace: posting.google.com 1042016468 18522 127.0.0.1 (8 Jan 2003 09:01:08
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: 8 Jan 2003 09:01:08 GMT
Xref: archiver1.google.com comp.lang.ada:32734
Date: 2003-01-08T09:01:08+00:00
List-Id: <comp.lang.ada>

Martin Klaiber:

> I'm only an Ada-beginner, but I'd say that Ada is so much more powerful
> than Pascal that they hardly can be compared at all. But I also found
> three things which I miss in Ada compared to Borland Pascal.
> 
> First, it would be nice, if an object in Ada would know it's own
> variables without naming them explicitly.
...
> It's not a big thing, but sometimes it leads to a lot of writing. Yes,
> I know I can rename variables, but I still wonder why an object in Ada
> doesn't know it's own variables.

In fact, you are missing BP's prefixed OO notation (object.Method).
You will certainly find fierce debates in c.l.a archives about it.
I survive by using always "o" as the object parameter.
The explicit has maybe the merit of readability over concision
(analogous to Pascal's "with" and its absence in Ada).

> Second, it would be nice, if Ada would allow to change internal
> variables of an object also in functions. So, the following is not
> valid code but it would be nice if it was, IMHO.

>   function IncMonth (Calendar : in out type_Calendar) return boolean;
>   function IncYear (Calendar : in out type_Calendar) return boolean;

> Of course the same thing can be done with procedures and a boolean
> parameter. But IMHO it's less elegant and less intuitive. [...]

Also subject to debates... you say it's intuitive because you are
accustomed to it. But look at your example. Normally, the basic role
of a function is to give a value in function of other (the parameters).
In your case the main information is what you do to "Calendar" and
the result has a minor role - quite strange... It would be more
elegant and intuitive (and also efficient) to write

  procedure IncMonth (Calendar : in out type_Calendar) is
  begin
    if Calendar.Month = 12 then
      IncYear (Calendar);
      Calendar.Month := 1;
    else
      Calendar.Month := Calendar.Month + 1;
    end if;
  end IncMonth;

  procedure function IncYear (Calendar : in out type_Calendar) is
  begin
    if Calendar.Year < 3000 then
      Calendar.Year := Calendar.Year + 1;
    else
      raise Year_out_of_range;
    end if;
  end IncYear;

Don't forget, you have the exceptions... it saves a lot of transporting
error codes and acrobatic expressions...
________________________________________________________
Gautier  --  http://www.mysunrise.ch/users/gdm/gsoft.htm

NB: For a direct answer, e-mail address on the Web site!