sub enum (\@$$){
...
}
use feature 'state';
while ( enum @a => state $value, state $i ){
  print "enum: $i $value\n";
}


##</code><code>##

  DB<7> sub tst ($;$) {print scalar @_ }
 
  DB<8> tst(my($x,$y))
1


##</code><code>##

  DB<3> sub tst  {print scalar @_ }<P>

  DB<4> tst( my ($a,$b))
2
  DB<5> tst( my ($a,$b,$c))
3
  DB<6> tst( my ($a,$b,$c,$d))
4