Path: utzoo!attcan!uunet!mcsun!ukc!edcastle!cs.ed.ac.uk!cs.edinburgh.ac.uk!nick
From: nick@cs.edinburgh.ac.uk (Nick Rothwell)
Newsgroups: comp.lang.misc
Subject: Re: Need reference for "firewall" modularization
Keywords: Error handling, damage control, software engineering
Message-ID: <961@skye.cs.ed.ac.uk>
Date: 26 Oct 90 11:17:41 GMT
References: <Oct.24.22.04.05.1990.393@cadenza.rutgers.edu> <1990Oct25.193935.375@arnor.uucp>
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Reply-To: nick@lfcs.ed.ac.uk
Organization: Wavetables 'R' Us
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In article <1990Oct25.193935.375@arnor.uucp>, strom@arnor.uucp writes:
> Conventional type-checking is inadequate, since
> many program bugs are the result of issuing otherwise correct operations
> *in the wrong order* --- e.g. storing into a buffer before it has been
> allocated.

Just a minor point here - that's a fault with conventional procedural
languages with assignable variables, and nothing to do with typechecking.
Functional and logic languages don't have this problem at all.

> In our experience, the potential for
> error detection, the gain in efficiency of cross-application communication,
> and the security/reliability/debugging advantages of firewalls are
> benefits which are well worth the costs.


-- 
Nick Rothwell,	Laboratory for Foundations of Computer Science, Edinburgh.
		nick@lfcs.ed.ac.uk    <Atlantic Ocean>!mcsun!ukc!lfcs!nick
~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~
 "Now remember - and this is most important - you must think in Russian."