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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,f25e853f410d55da
X-Google-Attributes: gid103376,public
From: dennison@telepath.com
Subject: Re: Time to join the fold?
Date: 1999/01/25
Message-ID: <78iq2m$br9$1@nnrp1.dejanews.com>#1/1
X-Deja-AN: 436784047
References: <78abg4$cnc$1@its.hooked.net>
 <F5zFII.GrI.0.-s@inmet.camb.inmet.com> <78i8s4$hth$1@its.hooked.net>
X-Http-Proxy: 1.0 x8.dejanews.com:80 (Squid/1.1.22) for client 204.48.27.130
Organization: Deja News - The Leader in Internet Discussion
X-Article-Creation-Date: Mon Jan 25 22:09:33 1999 GMT
Newsgroups: comp.lang.ada
X-Http-User-Agent: Mozilla/4.5 [en] (WinNT; I)
Date: 1999-01-25T00:00:00+00:00
List-Id: <comp.lang.ada>

In article <78i8s4$hth$1@its.hooked.net>,
  "Mike Silva" <mjsilva@jps.net> wrote:

> Now for another question.  Some people have mentioned getting into the Ada
> "mind-set".  What are the main components of this mind-set?  What, IOW,
> should I pay special attention to in order to avoid simply writing "C in
> Ada" (whatever that might mean).  Thanks again for the help.

For the most part, that's just something you'll have to work out. (Is there a
support group for recovering C coders?)

One good example that does spring to mind is string handling. C coders want
to be able to assign a length 5 string into a length 12 string because strcpy
would do that for them. So their first try tends to be:  Str : String(1..12);
begin  Str := "hiho!";

Which won't work in Ada because the two arrays aren't the same size. Then
they will try using a loop or slice to assign the 5 characters only. Then
they try to print the twelve character string. This won't do what they want,
because Ada strings aren't null terminated. Then they discover that they have
to instantiate a generic routine to ouput a number as a string, and they are
liable to get insanely frustrated.

The problem is that the approach is all wrong. Ada developers tend to handle
strings as literals or constants whenever possible. The '&' operator on
strings makes this much easier to deal with. Scalar numbers can be converted
to strings inline w/ "'image". In a severe jam a declare block can be used to
get a localized constant string, or one of the ada.strings packages can be
used.

This is just one example of many. I guess the main point is that you have to
think in terms of the tools at your disposal, not in terms of the tools you
*don't* have.

T.E.D.

-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/       Search, Read, Discuss, or Start Your Own