class.pl

use v6;

class T {
    has $.with_accessor;
    has $!without_accessor;

    method new ($i as Int) {
        self.bless(*, with_accessor => $i, without_accessor => $i);
    }

    method say_attr {
        say "with: $!with_accessor";
        say "without: $!without_accessor";
    }
}


my $t = T.new(1);
$t.say_attr;

# 実行結果
#
# perl6 class.pl 
# with: 1
# Use of uninitialized value in string context
# without: