On Sat, Jun 15, 2002 at 09:08:31AM -0500, Jonathan Scott Duff wrote: > At the very least you should be able to do this: > > rule leftop($leftop,$op;$rightop) { > $other := { (defined $rightop) ?? $rightop :: $leftop } > <$leftop> [$op <$other>]* > }
Or maybe rule leftop($leftop,$op;$rightop) { <$leftop> [$op <{ $rightop // $leftop }>]* } Marcel -- We are Perl. Your table will be assimilated. Your waiter will adapt to service us. Surrender your beer. Resistance is futile. -- London.pm strategy aka "embrace and extend" aka "mark and sweep"