use Date::Japanese::Era;

my $era = Date::Japanese::Era->new(2006, 4, 5);
print "2006 is " . uc($era->name_ascii) . " " . $era->year . "\n";

for my $Emperor (qw(heisei taishou meiji)) {
 $era = Date::Japanese::Era->new($Emperor, 6);
 print uc($Emperor) . " 6 is " . $era->gregorian_year . "\n"; 
}

2006 is HEISEI 18
HEISEI 6 is 1994
TAISHOU 6 is 1917
MEIJI 6 is 1873