my $ok;  # it's undef
if( ... ){ # going to actually set it
  $ok = $password eq $pass ? 1 : 0
}
...
if($ok){
  # do good stuff
}
...
if(!$ok){
  # if failed for any reason
}
...
if(defined $ok && !$ok){
  # if set to false
}
...
if(! defined $ok){
  # if unset
}
...
printf "Status: %s\n", (defined $ok ? ($ok?'yes':'no') : 'n/a');