Newsgroups: comp.lang.postscript
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!clarkson!grape.ecs.clarkson.edu!nelson
From: nelson@sun.soe.clarkson.edu (Russ Nelson)
Subject: Re: It *can* be done (was Re: Diatribe)
Reply-To: nelson@clutx.clarkson.edu (aka NELSON@CLUTX.BITNET)
Organization: Clarkson University, Potsdam NY
Date: 10 May 91 13:33:20
Message-ID: <NELSON.91May10133320@sun.clarkson.edu>
In-Reply-To: glenn@heaven.woodside.ca.us's message of 10 May 91 02:39:32 GMT
References: <NELSON.91May5214234@sun.clarkson.edu> <497@heaven.woodside.ca.us>
Sender: usenet@grape.ecs.clarkson.edu

In article <497@heaven.woodside.ca.us> glenn@heaven.woodside.ca.us (Glenn Reid) writes:

   Russ Nelson writes
   > In article <489@heaven.woodside.ca.us> glenn@heaven.woodside.ca.us (Glenn  
   Reid) writes:
   >    Imagine two carpenters building a door.  One builds the frame,
   >    the other builds the door.  Neither one is on-site, and
   >    neither has met the other.  They are both working from the
   >    "spec", or the blueprint.  How likely do you think it is that
   >    the door fits in the frame, that the latch lands squarely in
   >    the hole in the door frame, and that the hinges are set
   >    properly?  I wouldn't give it 1 chance in 100,000, even with
   >    experienced carpenters.
   > 
   > I'm afraid that you're revealing your ignorance here, Glenn (don't
   > worry, I've done it *lots* of times myself).  Not only *can* it be
   > done, it *has* been done.

   Sure it's been done.  But on the whole, it doesn't work that way
   very often.  Also, it's actually much easier to get timber framing
   right than it is to hang a door correctly.  I was, of course,
   exaggerating beyond trying to make a point in suggesting the odds
   to be so distant as 100,000 to 1, but the underlying point, that I
   think is still good, was that it's difficult for two companies to
   write software against a spec and then expect it to work the first
   time.

I agree, it is difficult.  But I also added that we might be able to do it
after we've had several centuries of experience doing it.

   Someone else (I think Tom) made a much more valid point
   than suggesting my ignorance (ignorance of what, by the
   way?).

Ignorant of a counterfoil to your argument.  Yes, timber framing is
less exact than hanging a door.  On the other hand, 300+ carpenters
made timbers from the same spec that mostly all fit together.  I think
that's an achievement of equal difficulty to the one you proposed.

   That point was that the software industry is often *compelled* to
   do simultaneous work from a specification, and doesn't usually have
   the luxury of interconnected testing.

The question is whether it's a luxury or whether it's necessary.  I think
we both agree that it's necessary.

--
--russ <nelson@clutx.clarkson.edu> I'm proud to be a humble Quaker.
Clear cutting is criminal, spiking trees is criminal, and using hyperbole of
this magnitude in a serious discussion is criminal.  -- Irv Chidsey
