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Date:	Wed, 26 May 1993 13:06:40 -0400
From:	haahr@mv.us.adobe.com (Paul Haahr)
Message-Id: <9305261706.AA29590@astro.mv.us.adobe.com>
To:	alan@oldp.astro.wisc.edu
Subject: Re: Differences between Duff's rc and Byron's
Cc:	rc@hawkwind.utcs.toronto.edu

> Actually, reading the Plan9 man pages was somewhat depressing:  two of
> the things I regard as unnecessary in Byron's rc ($^foo and newpgrp)
> have made it after a fashion in to Duff's implementation.

$^ is most definitely necessary.  ok, you can simulate the operation with:

	fn flatten {
		var = $1
		shift
		if (~$#* 0) {
			$var = ''
			return
		}
		$var = $1
		shift
		for (i = $*) {
			$var = $$var ^ ' ' ^ $i
		}
	}

and use

	flatten x $foo

for

	x = $^foo

but the operation itself is fundamental.  the concatenation semantics just
about require it.  (eval, for example, does flattening internally.)

newpgrp on the other hand is a hack.  it's there because otherwise rc
would be much less usable on some (admittedly broken) systems.

paul