use Scalar::Util qw/dualvar/;
 
my $false = dualvar 0, "false";
my $true = dualvar 1, "true";
 
say $true;
say "stringification:" . $true;
say "numification: " . (0+$true);
 
say $false;
say "stringification: " . $false;
say "numification: " . (0+$false);