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From: info-modula-2@ucbvax.UUCP
Newsgroups: net.lang.mod2
Subject: Re: exceptions in Modula-2
Message-ID: <8602032056.AA26124@calmasd.CALMA.UUCP>
Date: Mon, 3-Feb-86 15:56:20 EST
Article-I.D.: calmasd.8602032056.AA26124
Posted: Mon Feb  3 15:56:20 1986
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I was not happy with the Computer Language article since it gave only
weak justification for its proposed extensions.  More constructive
would have been a list of functionality that is missing or inconvenient
according to the current language definition, and an analysis of the
least damaging solution.

I've heard complaints from language designers that users and compiler
writers really shouldn't be in the business of changing a language.
Taken too literally, of course, this is silly, but there is a tendency
to add a quick and dirty feature rather than think hard about how to
use the existing language definition to accomplish the goal.  I heard
Wirth speak last February and he admitted that Modula-2 was not
perfect, but he wholeheartedly disapproves of random extensions.

As for exceptions, my impression is that the exception-handler of Ada
is similar to the user-specified error procedures in the Volition
libraries.  Both schemes have the demerit of losing context -- you
cannot patch up the problem and restart the offending block of code.

--Bob Hofkin