Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!jpl-devvax!lwall
From: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Newsgroups: comp.lang.perl
Subject: Re: $1, $2 not being set - array/scalar context confusion?
Message-ID: <7521@jpl-devvax.JPL.NASA.GOV>
Date: 23 Mar 90 17:35:05 GMT
References: <1990Mar23.120241.20340@uvaarpa.Virginia.EDU>
Reply-To: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 22

In article <1990Mar23.120241.20340@uvaarpa.Virginia.EDU> alfie%cs.warwick.ac.uk@nsfnet-relay.ac.uk writes:
: sub expand {
:     local($tmp) = @_;
:     $tmp =~ s/\s+([-,])\s+/\1/g;		# remove non-sep spaces
:     $tmp =~ s/\s+/,/g;				# replace sep spaces with ","
:     $tmp =~ s/(\d+)-(\d+)/join(',',$1..$2)/eg;	# perform range expansion
:     if ( $tmp =~ /([^\d,])/ ) {			# check remainder is valid
: 	warn "bad character '$1' in expand\n";
: 	$tmp = "";				# all bets are off!
:     }
:     split(',',$tmp);				# split and return elements


If you say

	print join(':',&expand('1, 2, 3 ,4'));

you'll see that you have a bug.  The first substitution only works if there's
whitespace on both sides of the comma or hyphen.  Changing the pluses to
stars would fix that.

Larry