Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!linus!decvax!harpo!floyd!clyde!ihnp4!inuxc!pur-ee!uiucdcs!uicsl!preece
From: preece@uicsl.UUCP
Newsgroups: net.cog-eng
Subject: Re: Re: expert-friendly: are long names - (nf)
Message-ID: <4208@uiucdcs.UUCP>
Date: Tue, 29-Nov-83 22:42:37 EST
Article-I.D.: uiucdcs.4208
Posted: Tue Nov 29 22:42:37 1983
Date-Received: Thu, 1-Dec-83 22:31:58 EST
Lines: 23

#R:watmath:-619600:uicsl:21500004:000:1103
uicsl!preece    Nov 29 09:38:00 1983

	If you are designing a command language that is supposed to have a
	precise meaning and work first time and every time, you can't use
	heuristics that change the meaning of commands.  Every command must
	have a unique interpretation, regardless of the current environment
	in which it is invoked.  You can't have "chmod 0666 0777" change
	meaning depending on whether the current directory contains a file
	named "0666" or "0777".
----------
One of the reasons for having heuristics is to allow the command interpreter
to make exactly that kind of change.  This should be perfectly reasonable
even to naive users.  I don't expect the command '!c' to do the same thing
every time -- I know it depends on the context.  I know that if I walk into
our secretary's office and say 'Call Linda' a call will be made to a
different person than if I walk into one of my colleague's office and
say the same thing.  One of the things naive users don't like about
computers is exactly that inability to interpret commands sensibly,
in the context in which they are offered.

scott preece
ihnp4!uiucdcs!uicsl!preece