Re: Differences between Duff's rc and Byron's

[haahr@mv.us.adobe.com (Paul Haahr)]

> 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