Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83 (MC840302); site mcvax.UUCP
Path: utzoo!watmath!clyde!floyd!cmcl2!philabs!mcvax!guido
From: guido@mcvax.UUCP (Guido van Rossum)
Newsgroups: net.cog-eng
Subject: Re: name=value or -n value
Message-ID: <5769@mcvax.UUCP>
Date: Thu, 29-Mar-84 16:03:44 EST
Article-I.D.: mcvax.5769
Posted: Thu Mar 29 16:03:44 1984
Date-Received: Fri, 30-Mar-84 07:01:51 EST
References: <2853@fortune.UUCP> <1094@sdchema.UUCP> <3608@utcsrgv.UUCP>
Organization: "Stamp Out Basic" Committee, CWI, Amsterdam
Lines: 47

This discussion seems to run away a bit.  'T is nice to know that the
DEC-10/20 users are still listening to us, but I think that we should
separate the design of a standard for option parsing (which we can do
right now, with small steps in the desired direction) from a scheme
where at any moment one can ask for a list of possibilities, etc.

(I know the latter from Emacs, and like it very much; but it should
be part of a *visual* interface, and there will be lots of problems
before we have a universally accepted standard along the Unix lines.
I don't think the ncsh program of which we got some examples would give
the right answer to
	$ GREP C<?>
or it would have to know an awful lot about what it's doing...)

As for option syntax, the getopt parser and associated proposal
are a step in the right direction that even the most conservative
Unixophiles are willing to conform to.  (PLEASE POST IT!  A standard
which can only be adopted by System N licensees is of no use to those
writing software that is supposed to be portable to all V7 look-alike
systems -- like myself.)

Personally I agree with the person who said that bundling options
is nice, but that having longer option names is nicer in the long run.
This could be a gradual change, where only new programs allow
longer option names (and abbreviations!) and bundling disappears
slowly.  I don't use bundling very often except for ls and programs
(tar, ps) which require bundling.  Actually I never implemented bundling
in the many option parsers I have written myself during the years.

On using environment variables: the general problem is probably that
one option name can have meaning to lots of programs, and it is not
at all clear that you want it set to the same value for all those.
(Yes, of course this fact alone would cause better option names to
be devised so that the same option name has the same meaning throughout
the system; in fact we are doing this already with things such as
EDITOR, TERM etc.  But I wouldn't want 'verbose' to be set for all
the programs I run, and I think the same is true for most commonly
used option names.  So it's not a general solution.)

I don't believe that the Waterloo solution (+flag, -flag, opt=value)
will make it in the Unix world -- not all sites can convert every
program they acquire, and having a mix of two standards is worse
than having no tight standard but at least one convention.

--
	Guido van Rossum, "Stamp Out Basic" Committee, CWI, Amsterdam
	guido @ mcvax