From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on
	ip-172-31-74-118.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=-0.9 required=3.0 tests=BAYES_00,MSGID_SHORT,
	TO_NO_BRKTS_PCNT autolearn=no autolearn_force=no version=3.4.5-pre1
Date: 21 Apr 92 16:35:13 GMT
From: sampson@cod.nosc.mil  (Charles H. Sampson)
Subject: Re: Open comment to Ted Holden
Message-ID: <3785@cod.NOSC.MIL>
List-Id: <comp.lang.ada>

In article <2733@fedfil.UUCP> Ted Holden writes:

>Let me tell you about portability in Ada.  There are so many things you
>can't do in Ada, that any real-world application which is forced to use
>Ada to any extent ends up being a mixed-language application, and there's
>NOTHING less portable than that.  ...

     Whoops, there we go again.  Since Mr. Holden hadn't enlightened me
on this point my team and I have implemented a "pure" Ada application that
is 99.99% portable, running on VAXes (DEC Ada), IBM PCs (Alsys Ada) and
the Navy's UYK-43 (Ada/L).  I quibble about calling it pure Ada because
it has to call some non-standard packages.  The 0.01% of non-portability
comes from inherent operating system differences which we chose to honor
rather than ignore: The way you pick up command line parameters in VAXes
and PCs and the fact that there are none for the UYK-43.  We could have
handled all parameter input using Text_IO with prompts, of course, but
we chose to make the VAX version look like a VAX program, the PC version
look like a PC program, and the UYK-43 version look like a poor man's
Macintosh.   The impurities arose for the same reason.

     Just think, if I had known this was impossible, we might have been
forced to use a real software engineering language like C!

				Charlie