The elsif is just a shorter way of saying:

if(1) {
  print 'true'
}
else {
  if(1) {
    print 'false, true'
  }
}
[download]

and so you could write this:

unless(1) {
  print 'false'
}
else {
  unless(1) {
    print 'true, false'
  }
}
[download]

But it would be pretty wierd to use that in real life code.