by request in the chatterbox, a simple undo:

sub stringRangeToList { 
  my $foo = shift; 
  $foo =~ s/-/../g; 
  return eval $foo;
}
[download]

or, if you want string-to-string, this maybe seems more perlish:

sub stringRangeToStringList { 
  my $foo = shift; 
  $foo =~ s/(\d+)-(\d+)/join ',',$1..$2/eg;
  return $foo;
}
[download]

the usual caveat about 0-led numbers applies to the first and, in fact, it can take hex values (though it returns them as ints, which means they are likely to print as decimal if you don't pay attention). for reasons i'm not clear on, the 0-led thing doesn't happen to the second, though that's nicely consistent with its willful mistreatment of hex numbers. in fact, with no strict ('subs'), the first can take letter-ranges, as well.

neither responds particularly surprisingly, nor particularly well, to "3-5-7". error checking is left as an exercise to the reader. use at your own risk. these snippets were not tested on live animals; no test data was harmed in the design, creation, or testing of these snippets.