#! /usr/bin/perl -w

use strict;

my $x1 = 'aaa bbb cc';
my $x2 = 'aa, bb, cc';

print join( '-', split(/[\s,]+/, $x1)), "\n";  
print join( '-', split(/[\s,]+/, $x2)), "\n";

##</code><code>##

aaa-bbb-cc
aa-bb-cc

##</code><code>##

% perl -v

This is perl, v5.8.0 built for i386-freebsd-64int